Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
19 May

A Metabolic Paradigm Shift, or Why Fat is the Preferred Fuel for Human Metabolism

newparadigmThere’s a good reason so many people (mostly the sugar-burners, whose disparate group includes fruitarians, veg*ans, HEDers, body-builders, most MDs, the USDA and virtually every RD program in the country) can’t seem to grasp why a lower carb, Primal approach to eating is a better choice for health and fitness: their fundamental paradigm – the core theory that underpins everything else in that belief system – is flawed. They remain slaves to the antiquated notion that glucose is the king of fuels, so they live their lives in a fear of running low. The truth is, fat is the preferred fuel of human metabolism and has been for most of human evolution. Under normal human circumstances, we actually require only minimal amounts of glucose, most or all of which can be supplied by the liver as needed on a daily basis. The simple SAD fact that carbs/glucose are so readily available and cheap today doesn’t mean that we should depend on them as a primary source of fuel or revere them so highly. In fact, it is this blind allegiance to the “Carb Paradigm” that has driven so many of us to experience the vast array of metabolic problems that threaten to overwhelm our health care system.

It boggles my mind that such a large segment of the so-called health and fitness community would continue to defend high carbohydrate diets with such tenacity. It should all be very obvious by now. The studies keep piling up indicating that carbohydrate intake is the major variable in determining body composition and that excess glucose from carbohydrate intake (especially from processed grains and sugars) is the primary culprit in obesity and in many disease processes. It follows logically that if you can limit carb intake to a range of which is absolutely necessary (and even up to 50 grams a day over) and make the difference up with tasty fats and protein, you can literally reprogram your genes back to the evolutionary-based factory setting you had at birth – the setting that offered you the opportunity to start life as a truly efficient fat-burning organism and to continue to do so for the rest of your life as long as you send the right signals to your genes. Becoming an efficient fat-burner is the major premise of the Primal Blueprint eating and exercise strategies.

BParadigmShiftut logic doesn’t rule when you are stuck in the Carb Paradigm, so I still see some misguided bloggers decrying the Primal Blueprint eating strategy as potentially harmful for its relatively low carb intake or stating that my advice to “generally keep carbs under 150 grams a day unless you’re an athlete” is ridiculous. How many more times do I have to overhear a trainer advising a still-portly client to “eat 5 or 6 small meals throughout the day, always with some carbs, so you keep your blood sugar up and don’t go into starvation mode.”? It’s time to stop this nonsense and reframe the current views of human metabolism to accurately reflect the two and a half million years of evolution that shaped the current human genome – a perfect DNA recipe that fully expects us from birth to function largely on fats.

It’s time for a Metabolic Paradigm Shift within the health and fitness world.

The Faulty Carb Paradigm “Logic” Goes Something Like This

The basic underlying assumption is that glucose is the preferred fuel of most cells; BUT, because we can’t store very much glucose (as glycogen in liver and muscles), we need to provide a continuous source of glucose in the form of exogenous carbohydrate (high carb meals) to keep the brain, blood, and certain organs humming along and the muscles primed for activity. AND, if we don’t feed ourselves enough carbohydrate every few hours, our blood sugar will drop and we’ll go into “starvation mode” and cannibalize our precious muscle tissue. AND any lack of regular glucose refilling (i.e. skipping a meal or fasting) will cause cortisol to rise, which will have additional deleterious effects. FURTHERMORE, an excess of glucose in the bloodstream is known to raise insulin and will predispose excess calories (from all sources) to be stored as fat. THEREFORE, we should also be doing a lot of moderate-to-heavy cardio or lifting activity most days to burn off this excess stored body fat. HOWEVER, if we want to be ready and able to exercise frequently and strenuously to burn off our stored fat, we need to eat lots of complex carbohydrates between workouts to refill our glycogen stores. And ULTIMATELY, the only way to lose weight is to restrict calories (calories in<calories out), BUT if you’re working out regularly, it’s almost impossible to maintain a calorie-restricted regimen and still be able to work out hard enough to burn appreciable calories. Sheesh.

treadmill

Sure, there are exceptions, like the driven and genetically gifted types, who can train long hours, refuel on carbs and not add much body fat (hey, I was one). But unless you love to work out incessantly and have really lucky familial genes, the Carb Paradigm is an unsustainable and ridiculous literal and figurative treadmill, a self-fulfilling prophecy for most people who tend to gain weight steadily and insidiously over the years and wonder why. If you are one of the 60+% of the American population who is overweight, the above scenario plays itself out because you have spent your life programming your genes in the direction of being an effective sugar burner and, as a result, have become dependent on a fresh supply of sugar (carbs) every few hours. Naturally, in the presence of all that glucose, and provided you actually do some exercise, your genes will eventually get the signals to up-regulate the enzyme systems, pathways and receptors involved in sugar-burning and fat storage and they’ll down-regulate all those involved in accessing and burning fat for energy. Of course, that doesn’t make it right, but it sure makes it appear as if glucose is king. What makes it worse, if you don’t exercise, you head down the path to insulin resistance and/or obesity.

The Problem: The Basic Assumption of the Carb Paradigm is Wrong

Glucose is not the preferred fuel of muscle cells under normal human resting metabolic conditions or even under most normal human movement patterns (exercise). Fat is. Sure, given an unlimited supply of glucose and regular refilling of glycogen stores, skeletal muscle will burn through it during exercise the same way a fire burns through kindling when that’s all you have to offer. The body can shift carbohydrate oxidation to keep up with intake. But skeletal muscle can burn fat with great efficiency (and far less oxidative fallout) at relatively high outputs for very long bouts. Cardiac muscle actually prefers ketones, and the brain can run just fine (maybe even optimally) on a blend of ketones and minimal glucose.  Our survival as a species has depended on these evolutionary adaptations away from glucose dependency. Entire civilizations have existed for ages on what is practically a zero-carb diet. Think about this: there is actually no requirement for any “essential dietary carbohydrates” in human nutrition. It’s possible to live a very long and healthy life never consuming much – if any – in the way of carbs, provided you get adequate dietary protein and fat. The same can’t be said for going too long without protein or fat. Cut too far back on either of those macronutrients and you will eventually get sick and die.

The Evolutionary Model

Fat and protein were the dominant macronutrients (when food was even available) over the majority of our two-and-a-half million years as evolving humans. The lack of regular access to food and a scarcity of carbohydrates for much of this time necessitated that we adapt efficient pathways to readily store and access body fat for energy if we were to survive day-to-day and generation-to-generation. Our movement patterns were such that we never required large amounts of glucose or that we needed to store very much glycogen. It was predominantly fats, ketones and the minimal infusion of glucose via gluconeogenesis that got us here. Dietary carbs were insignificant. In fact, when you consider how ridiculously small the body’s glycogen reservoirs are, you understand that it would have been impossible for us to survive as a species if glucose were truly the “preferred” fuel. The liver, the main back-up glycogen/glucose storage facility for the brain and other glucose-burning organs, can only store about 100 grams of glycogen. Less than a day’s worth. Your muscles can only hold another 350-500 grams, barely enough to run for 90 minutes at a reasonable clip, and that glycogen isn’t even available to provide fuel for the brain. Meanwhile, we have a virtually unlimited storage capacity for fat (like 100,000 grams or close to a million calories on some people). The reason glycogen storage wasn’t necessary is because, between our copious fat storage capability, easy access to fats as fuel, gluconeogenesis and ketones, we just didn’t need much. Evolution tends not to reward structures or functions that take up unnecessary space or waste energy.

So How Much Glucose Do You Really Need?

Much less than most people assume. At any one time, the total amount of glucose dissolved in the bloodstream of a healthy non-diabetic is equivalent to only a teaspoon (maybe 5 grams). Much more than that is toxic; much less than that and you pass out. That’s not much range for a so-called “preferred” fuel, is it? Several studies have shown that under normal low MET conditions (at rest or low-to mid- levels of activity such as walking and easy work) the body only needs about 5 grams of glucose an hour. And that’s for people who aren’t yet fat-adapted or keto-adapted. The brain is the major consumer of glucose, needing maybe 120 grams a day in people who aren’t yet on a low carb eating program. Low carb eating reduces the brain’s glucose requirements considerably, and those who are very low carb (VLC) and keto-adapted may only require about 30 grams of glucose per day to fuel the brain (and little-to-none to fuel the muscles at <75% max efforts). Twenty of those grams can come from glycerol (a byproduct of fat metabolism) and the balance from gluconeogenesis in the liver (which can actually make up to a whopping 150 grams a day if you haven’t metabolically damaged it with NAFLD through fructose overdosing). Bottom line, unless you are a physical laborer or are training (exercising) hard on a daily basis, once you become fat-adapted, you probably don’t ever need to consume more than 150 grams of dietary carbs – and you can probably thrive on far less. Many PBers do very well (including working out) on 30-70 grams a day.

The Fat Paradigm

The Fat Paradigm, under which the human species has thrived quite effectively for two and a half million years, recognizes that human metabolism is pre-programmed by evolution to be primarily fat-based (the real preferred fuel). In other words, our genes expect us to function optimally when we consume fats and can easily access our stored fat. The Fat Paradigm acknowledges that the body is able to manufacture adequate glucose as needed. It acknowledges that most typical human movement patterns can be fueled almost entirely by fats and/or ketones (PDF) if need be, but can draw on glycogen when energy bursts are required (and which can then be replaced over time). It acknowledges that fat (and cholesterol) are not the proximate cause of heart disease. It acknowledges that fat cells are designed to release stored fatty acids as required, especially during times of scarcity or fasting. It allows for intermittent fasting as a means of accelerating fat loss without sacrificing muscle tissue. It increases insulin sensitivity, modulates energy and mood swings, and allows for a normal and healthy drop in hunger and cravings. There is a downside, however: you can’t train long and hard day-in and day-out in the fat paradigm.

Now then, having explained all this, please understand that I am not carb phobic. I actually permit more carbs in the Primal Blueprint than many other low carb eating strategies. I prefer to view carbs as the “elective” macronutrient, as a tool to use to manipulate your glycogen levels as needed. Low carb isn’t even the main objective of eating in the PB: eliminating grains, sugars and seed oils are the primary objective. Of course, when you get rid of that crap and naturally limit your carb intake to veggies, root tubers and a few fruits, you almost invariably decrease carbs to under 150 grams a day. And that emulates our ancestral dietary intake.

I came up with a simple Carbohydrate Curve a few years ago that offers a pretty concise picture of where most people ought to fall if they are seeking optimum health and energy, depending on their size, weight, sex, age, goals, etc. Now, many hundreds of thousands of user experiences later, I am finding that the Curve is pretty much spot on for a large segment of the population.

Picture2

When I say generally that a chronic intake of over 150 grams of carbs can lead to insidious weight gain over a lifetime, I am factoring in the concept that many people are at the effect of a familial genetic predisposition to storing fat easily under the carb paradigm (the 60+% overweight). I am also factoring in the drop in metabolism that happens naturally with age, as well as the fact that PBers don’t NEED to purge and refill glycogen stores every day via exercise. Yes, there are some people (a small percentage of outliers) who might maintain pretty decent body composition at up to 300 grams a day on little exercise. I would bet that they also are selective about the carb sources and do a better job of controlling overall calories, so there’s little excess to store. For most of the population, that 150 mark remains a good average level for maintaining ideal body composition.

Well, that was a lot to digest today. You see where I’m going with this. I need your help in showing the health community that their basic assumptions are wrong and that they need to make a Metabolic Paradigm Shift. I’m sure there will be lots of specific questions, so bring  ‘em on and I’ll do a follow up post in a week or two.

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. To more fully answer the question, “Why don’t elite athletes use a low carb diet:

    Matt posted a fair and full response, but I want to say that perhaps they would try it – if the zeitgeist of the carb-loading athlete were not so strong. Pair that with the commercial drive to push the limits of human performance beyond normal limits and you have carb loading, steroids and other damaging methods. Does adding nitro to your household car improve speed bursts? Yes. Is it the preferred method of fueling your car? No.

    We may never know what athletes can do on a more evolutionary diet. I don’t expect the pendulum to swing that far back in the 20 years I might have left. It’s been 12 years since I left the carbohydrate addiction behind and I still can’t find a doctor who supports me in my diet, even though they hold the records in their hands. The CW, the myths, the USDA guidelines are just too strong, and have have the full force of Big Agri/Pharma Lobbyists behind them.

    Bill DeWitt wrote on May 25th, 2011
    • GROK ON>>>>

      Daveman wrote on May 25th, 2011
  2. I wouldn’t eat corn anything even if you paid me to….
    specially corn starch..
    choking down starchy dust?…not for me…Primal man did just fine without it and man can continue to do just fine without it..And some of the most EXPLOSIVE athletes I know..Eat Paleo/Primal …especially the Crossfit monsters…And I know em…and they wouldn’t eat corn anything either…

    Daveman wrote on May 25th, 2011
  3. Of all the things many humans, and particularly Americans have “forgotten” how to do, eating, tops the list.

    Extrapolate that across all of human activity and I shudder to think what that spells for us.

    smarmyrealist wrote on May 26th, 2011
  4. Of course, one thing I have to admit is that in nature, carnivores are NEVER able to outrun herbivores. Not ONCE, EVER! Which is why all carnivores died out so many millions of years ago…

    Bill DeWitt wrote on May 26th, 2011
  5. this link may point to some science for those so inclined.
    http://sciencenewsmagazine.org/pages/pdfs/data/1996/149-18/14918-20.pdf

    tim_lebsack wrote on May 26th, 2011
  6. How much can you increase your intake if you’re working out? Even on workout or really active days, I stay around 150, occasionally a bit higher. Still too low? Sometimes I find myself hitting a wall…

    Lisa wrote on May 26th, 2011
    • I think you have to play with it in order to figure out what is optimal for you and your level of activity. If you find yourself bonking out, then you probably need more easily accessible energy, and since it takes work and time to get additional energy out of fat, it makes sense that the body would preferentially select ready to go energy. So if you need more, take more in. Stop when you feel better.

      Hal wrote on May 26th, 2011
      • Looks like 170 is a good area for me, surprisingly! Might want to rethink 170 as an insidious weight gain zone. ;)

        Lisa wrote on May 28th, 2011
  7. I just want to make a small contribution to this thread in terms of “our neolithic ancestors” and high carb diets.

    I am an academic working cross-discipline in history, literature, classics, and politics, with a specific interest in the lives of the ordinary working classes from the classical period to the 19th century West.

    What people maybe do not realise is that, even two hundred years ago, “bread” was nowhere near the kind of product we produce and consume today.

    If you recreate the ingredients, which is possible in Britain as we still have a few working watermills with traditional mill stones to create the right kind of flour, and methods by which Western European people made bread in the early 19th century, you end up with a very dense, compact, heavy, close-crumb product that is very “meaty” in texture.

    It is very difficult to eat more than a couple of slices of these loaves, and they were made with traditional honey, not refined sugar. They were also very small, compared to what we see today. Remember also that the “white flour” of the time was not bleached, just sieved, and cost a premium that many could not afford. Cheaper flour was could be up to 50 percent husk.

    To go back to Tudor/Stuart England, the diets of rural English peasantry revolved around what they could grow in their small cottage gardens and what they could forage in forests. These people lived on bone broths with scraps of root vegetables and meat, and dairy products if they were wealthy enough to own a cow or some chickens. There were oats, however.

    Again, if you were wealthy in the Tudor/Stuart period, you ate meat. Lots of meat. All the time. In fact, what is noticeable is the link between obesity amongst the elite and merchant classes and the consumption of ale, beer, mead and wine.

    So it is not really accurate to say, if you are from a Western European heritage, that our “ancestors” in the last 1000 years ate high carb diets. It really depended on who you were, and where you were. Indeed, most non-elite/non-merchant class English people prior to the 19th century lived on what we would probably see as a rather Primal Diet — remember there is no rice, no pasta, and, before the Tudor period, no potatoes, and honey is the sweetener of choice. Pastry is made with lard or suet, and they didn’t really eat a lot of it.

    Alex wrote on May 29th, 2011
    • Hi Alex,

      Nice points you raise.

      The other issue is that even if you take the 10,000 years generally accepted as how long the human species has been eating grains, this is not as long as it sounds from an evolutionary point of view.

      If you take modern humans being about 200,000 years old in terms of physiology and metabolic functions, then 10,000 years is not that long. Put it on a 24 hour clock (NOT a 12 hour clock) and that means that we have only been eating grains for the last 72 minutes (out of 1440 minutes)!!!, or approximately 1 hour in the last 24.

      Now we may have adapted to tolerate this food source and certain individuals may even have genetic variation from the norm that allows them to THRIVE on this type of diet, but based on human history, and even allowing for the observed acceleration in evolution for humans in recent times it will likely be another 50,000+ years before we would have a sufficient portion of the population that has evolved to be “homowheatus” as I like to call them, and that would thrive on a high grain diet.

      Note the difference, in biology you can adapt to tolerate something, that does not mean you are at the point where you have evolved to THRIVE on that thing.

      Anyway, as you point out, few people would have appropriately adapted to a high carb diet within a 1000 year period.

      Also, the other common mistake people make when first reading about the Primal Blueprint or similar diets is that they think the no grains approach in the Primal Blueprint means low/no carb diet.

      It just means lower carb. With carbs still coming from non-grain sources. You limit your carbs by not eating grains and refined carbs of any kind.

      You can eat fruit, unless you want to maximise weight loss, and thus limit your carbs even more.

      At not stage (other than small fasts), do you reduce you carbs below an amount that could keep your brain ticking along on carbs if needed.

      Luke wrote on May 31st, 2011
  8. i didn’t read all of the pages of comment, so please forgive me if i’m redundant, but i highly recommend Sally Fallon’s “Nourishing Traditions”. it talks about what healthy historical cultures *really* ate, and one cookbook you have to read cover-to-cover! it’s co-authored by Mary Enig, who probably knows more about dietary fats than anyone in the world.

    tess wrote on May 29th, 2011
  9. I have a simple question: if fat is the preferred fuel, and you follow PB nutrition, then why do you state “There is a downside, however: you can’t train long and hard day-in and day-out in the fat paradigm”? Don’t all of us have plenty of fat to supply energy for endurance training?

    Kelly wrote on May 30th, 2011
    • I work HARD…and I lift HEAVY…and I pretty much live on less than 50 grams of carbs per day..everyday.I have no problems GROKKING along…Everyone comes from different evolutionary genetic stock..and we all are different and can
      handle it different.
      FAt…CArbs…PRotien…just do it fresh and with no processed foods.GROK ON>>>

      Daveman wrote on May 30th, 2011
      • No, from an evolutionary perspective, we are all the same.

        Seth wrote on May 30th, 2011
  10. This post is ridiculous. The body requires carbohydrate for brain function, which is a physiological priority. The body doesn’t prefer fat and ketones (ketone bodies are derived from fatty acids when carbohydrate in the body is scarce; a desperate mechanism to get a form of carbohydrate for the brain). Here’s an experiment to find out what fuel the body prefers: keep insulin (a protein hormone that facilitates the transport of glucose (carbohydrate) across cellular membranes) away from a type 1 diabetic and see what happens.

    Fat does become the predominant fuel used by muscle at low levels of physical activity, but it is not preferred, but only to spare carbohydrates for moments when it’s critical (physical activity/survival).

    Seth wrote on May 30th, 2011
    • @Seth: It has been determined by real scientists, using real science, that the brain functions just fine on ketones. You are free, of course, to continue on your superstition-based diet if you so chose.

      Howard wrote on May 30th, 2011
      • Actually, no it hasn’t. Do you have any idea how and why ketone bodies are produced in the body? Please cite the research article(s) by these real scientists demonstrating that the brain is okay with just ketones.

        Seth wrote on May 30th, 2011
        • Do you have any idea why type 1 diabetics go into a coma and die? It’s not superstition, it’s education.

          Seth wrote on May 30th, 2011
        • If carbohydrates are so necessary to the human body, how did we survive the last ice-age?

          Ann wrote on June 6th, 2012
        • And you are confusing ketosis with ketoacidosis. Different conditions, different diets. Ketoacidosis is only dangerous for diabetics.

          Ann wrote on June 6th, 2012
  11. Almost a custom for those who disagree with a well reasoned, fully documented and entertaining post to repeat assertions we’ve all heard many times before, as if repeating them makes them more like science. For the record, the body can and does produce all the glucose it actually needs, so dietary sugars and carbs are not needed. Any amount of blood sugar over about a teaspoon full per hour is toxic, as many reputable news sources are finally admitting these last few weeks. That’s why we have insulin, to move it out of the blood, and keep it form killing us. That’s why T1 diabetics need shots of it, not only so that they can use the sugar, but so that it’s not in their blood, killing them.

    Bill DeWitt wrote on May 30th, 2011
    • Wow.

      Sugar in the blood will not kill you. Excessive amounts get excreted in the urine.

      What reputable news sources?

      Seth wrote on May 30th, 2011
      • Yes, blood glucose levels for diabetics are never checked and a high number is not at all worrisome.

        bradley wrote on May 30th, 2011
    • As a current doctoral student in human physiology, previously completing a masters degree in exercise physiology, I’m telling you that you are completely misinformed. This is a perfect example of the misinformation floating around out there concerning metabolism. The striking part is how the misinformed cling to it and believe it.

      Seth wrote on May 30th, 2011
      • As a graduate of a degree with biochemistry and evolutionary biology, and someone with experience in the pharmaceutical industry (now out due to what I now know) and working in the area of Type 2 diabetes, I’m telling you that you are completely misinformed. This is a perfect example of the misinformation floating around out there concerning metabolism by those indoctrinated in the conventional wisdom of exercise physiology (i.e. personal trainers with an degree). The striking part is how the misinformed (especially those climbing the academic ladder of the conventional wisdom) cling to it and believe it (without question, cause it is already in my head!!).

        ;-)

        Too easy

        Luke wrote on May 31st, 2011
        • I recognise you are getting your doctorate in human physiology, but obviously that means you get to skip the basic information on physiology…. otherwise you would/should have learnt about things like the role of the hormone insulin in promoting fat storage and preventing fat burning, the lack of a decent glycogen storage system (despite your dogma that carbs are vital – of so vital we would have evolved a decent carb storage system to rival fat storage) and the fact that evolution for nearly all animals chose FAT as a storage mechanism, hence it must be fine to run your body on fat!!! Oh and the completely one sided view of energy in = energy out, ignoring (or being ignorant of) the fact this equation runs both ways and describes a relationship, not a cause.

          Luke wrote on May 31st, 2011
    • Bill DeWitt:”For the record, the body can and does produce all the glucose it actually needs, so dietary sugars and carbs are not needed.”

      yes and it’s one of the reasons why we survived those thousands of winters. Our ancestors’ brains didn’t stop functioning properly when we had to rely on hunting & fishing (zero carbs) as our only source of food for months. The “You need X servings of carbs or you’ll die!!!” crowd needs to look at evolution & how we survived in the past, not at the USDA Food Pyramid/Plate.

      Michael wrote on September 15th, 2011
  12. So when my vegetarian diet led my BG readings to be in the 700s instead of around 100, you are saying that this was not a problem? Can I quote you on that when they schedule my amputation?

    As for reputable news, Look it up. There have been plenty of links posted. That way you can use YOUR idea of a reputable source. But look for hyperglycemia, not “why sugar is good for you”…

    Bill DeWitt wrote on May 30th, 2011
    • No, I don’t condone a vegatarian diet, nor did I even mention it.

      You made a claim that sugar is toxic and that this information supported by reputable sources. You should provide the source.

      Seth wrote on May 30th, 2011
  13. Argument by Authority works a lot better when you cite your sources and offer your credentials…. still a logical fallacy, but one that fools more people.

    Bill DeWitt wrote on May 30th, 2011
    • haha – you must cite your sources!

      I don’t have to, because I’m educated!!

      I don’t know if you are educated too, and even whether you are MORE educated than I am, but as I am brimming with self pride in my academic “achievements” I will ASSUME that I must be smarter than you (I mean I have a masters and am studying a doctorate – what are the chances you are “smarter” than me!!!)

      I fail to recognise that obtaining a qualification does not equate to experience of even knowledge in the real world.

      I also fail to recognise that whilst in common language having a masters and studying a doctorate is considered being “an academic”, in academia, until you have done research, preferably resulting in some new facts being revealed to the world, not just confirming what is already known (or worse assumed), you aren’t really an “academic”.

      However, most people assume people with degrees, especially advanced degrees are smart, so they will be swayed by my use of my qualifications (completed and currently underway) as proof enough of the facts I state!!!

      ;-)

      Luke wrote on May 31st, 2011
  14. Unless your plan is to avoid the question, the type of diet is not important. Tell me you believe that a BG reading of 700 is not a problem, or admit that hyperglycemia is one of the major causes of the eventual death of T2 Diabetics.

    If you have not looked up hyperglycemia by now, then you don’t want to learn, you just want to argue.

    Bill DeWitt wrote on May 30th, 2011
    • The major causes of death of type 2 diabetics are heart attack and stroke, not hyperglycemia.

      A BG of 700 is not good; it’s a problem. A BG of 700 doesn’t happen because carbohydrates are bad; it happens because of a poor diet and no exercise. A BG of 700 often occurs because the individual is insulin resistant (again, due to a poor diet and no regular exercise).

      I don’t need to look up hyperglycemia. Also, I always like to learn. That’s why I’m a graduate student.

      Seth wrote on May 30th, 2011
      • Ah Seth,

        The graduate student makes you a master of all information.

        Well I have worked with, and learnt from some of the leading endocrinologists and other specialists in the world that treat Type 2 (and Type 1) diabetes, including some at institutions such as the International Diabetes Institute.

        Your statement:

        “The major causes of death of type 2 diabetics are heart attack and stroke, not hyperglycemia”

        …is like saying the leading cause of death for gunshot victims is ingress of a bullet, not the firing of the gun.

        The damage to the vascular system, including the regulation of blood pressure by the kidneys is damaged by CHRONIC hyperglycemia. As a result after YEARS of elevated blood glucose (hyperglycemia) the damage to the vascular system results in heart attacks and strokes. DUH!!!

        Regarding your hypothesis that high blood glucose only occurs due to poor exercise and diet – again this is FALSE (e.g. Type 1 diabetics).

        You state “No, from an evolutionary perspective, we are all the same.” Whilst there is some truth to the fact we all evolved from likely a single female human ancestor, it is also a fallacy to state we are all the same in terms of evolution… CLEARLY there are physiological differences between people, some due to race, yet even within a race, there is genetic variation (in fact the variation is larger within a particular race). If you TRULY are studying to attain your doctorate in human physiology, I really do hope they teach you this basic fact. Even in conventional medicine it is recognised that certain people react differently and metabolise certain compounds differently from others. Proof of this is the fact that some people can take a drug with no effect, others taking the same dose can end up with severe side effects and even be so sensitive they die… clearly we may have a common evolutionary source, but we are NOT the same in terms of evolution, as environment and other factors shape our evolutionary path.

        You state:

        “The body requires carbohydrate for brain function, which is a physiological priority. The body doesn’t prefer fat and ketones (ketone bodies are derived from fatty acids when carbohydrate in the body is scarce; a desperate mechanism to get a form of carbohydrate for the brain). Here’s an experiment to find out what fuel the body prefers: keep insulin (a protein hormone that facilitates the transport of glucose (carbohydrate) across cellular membranes) away from a type 1 diabetic and see what happens.

        Fat does become the predominant fuel used by muscle at low levels of physical activity, but it is not preferred, but only to spare carbohydrates for moments when it’s critical (physical activity/survival).”

        SO MANY errors here it will take some time:

        1) Even if the brain needs carbohydrate as a preference, this does NOT equate to needing carbohydrate in the diet. It is a medical and scientific fact (and no I have no references at hand, as this is considered BASIC common knowledge – especially for someone as “educated” as you) that there are NO essential dietary requirements for carbohydrates. There ARE essential amino acids and fats, without them our bodily function is compromised. There IS a process in the body that converts proteins into carbohydrates (gluconeogenisis). This is a function of the liver, and is in fact one of the dysfuntions Type 2 diabetics suffer (their liver produces excess glucose, even when the blood glucose levels are already elevated). This is such a significant problem, that many of the new drugs for Type 2 diabetes under development target this process. If there is sufficient protein in the diet (in excess of basic needs), any excess can be converted into glucose vis gluconeogenisis. This is why body builders that eat too much protein, don’t realise most of the excess is pissed out or converted into glucose.

        The “experiment” is SUCH a fallacy and an example of poor debate on your part. Type 1 diabetics have a VERY different aetiology to Type 2 diabetics, and if you are in fact as educated as you claim to be you SHOULD know this, and as such you are either truly ignorant, or being deceptive so as to confuse those that may not know the difference.

        Type 1 diabetics have a condition that means their pancreas no longer produces sufficient insulin (if any at all). In the absence of ANY insulin, the body cannot utilise glucose. Additionally, as there is no insulin the bodies fat cells are signalled to release fatty acids as a energy source, and the type 1 diabetic quickly emaciates, additionally in certain cases they can enter diabetic ketoacidosis. If you do not know this, diabetic ketoacidosis is NOT the same as being in ketosis.

        The key here is the “acidosis” in ketoacidosis. All acidiosis states can be lethal (there are others other than ketoacidosis). They are essentially acidification of the blood.

        This is NOT the same as having ketone bodies in your blood stream, to suggest so is misleading.

        From wikipedia:

        “There are two major causes of ketoacidosis:

        Most commonly, ketoacidosis is diabetic ketoacidosis (DKA), resulting from increased fat metabolism due to a shortage of insulin. It is associated primarily with type I diabetes, and may result in a diabetic coma if left untreated.[4]

        Alcoholic ketoacidosis (AKA) presents infrequently, but can occur with acute alcohol intoxication, most often following a binge in alcoholics with acute or chronic liver or pancreatic disorders. Alcoholic ketoacidosis occurs more frequently following methanol or ethylene glycol intoxication than following intoxication with uncontaminated ethanol.[5]

        Ketoacidosis may also result from prolonged fasting or when following a ketogenic diet.[6]”

        I have included this last statement, as it is true, it MAY result from following a ketogenic diet, however you would have to be following it in the EXTREME. In fact outside of alcoholics and type 1 diabetics it is VERY rare, and even for them it is not at all a very common medical problem.

        You state:

        “You made a claim that sugar is toxic and that this information supported by reputable sources. You should provide the source”

        Two things here:

        1) Whilst I do not have references at hand (I am in a hotel at the moment), look up glucotoxicity. Again, in research with non-diabetics, pre-diabetics, Type 2 and type 1 diabetics there is evidence that elevated blood glucose (and not even that much mind you) has DIRECT glucotoxicity effects on the pancrease, in particular the beta cells (the VERY cells that produce insulin, which would in some way reduce the problem). This, as one professor in the area mentioned to me, is the great irony of the human body, the very cells that produce the hormone to reduce blood glucose are themselves DAMAGED by excess blood glucose. As a result if they fail to keep up with the amount of carbohydrate consumed (simple, complex, low GI or high GI – they ALL end up as glucose), they then get hammered, resulting in a reduced ability to keep up in the future. In fact, this fact suggests when we evolved we were not consuming vast amounts of glucose, if we did, there would be another mechanism that would have evolved to accommodate the beta cells that were damaged. We never evolved this system, because we never ate vast quantities of carbohydrates until we worked out how to access the carbs from the previously toxic grains and legumes we learnt how to cook enough to reduce their toxicity.

        2) You admonish others for not supplying references for their claims, yet you have NOT ONCE done the same. You use your education as you reference. Well sir I will invoke the same as you. I invoke me degrees in biochemistry and evolutionary biology, and years of experience in the pharmaceutical industry (reading countless journals in this topic), as well as my working in the area of type 2 diabetes. I acknowledge I don’t have a masters or a soon to be PhD, but then again, perhaps that is why I am not caught in a delusion that everything I learnt is absolute truth, and I don’t have the neurosis of using my education as a crutch to remain blinkered to any other views of the world. The fact you are a recent graduate and straight into a doctorate suggests to me you are someone heavy with education, but lacking life experience.

        You state you KNOW better than us because of what you learnt in attaining your masters degree in exercise physiology and during your current studies to attain your doctorate in human physiology… what an appalling state of affairs in the education system, when such an obvious flaw in your logic is beyond your recognition.

        What if what you have been taught is wrong? Just because you have a degree (masters or even doctorate) in bullshit, doesn’t make the bullshit any less composed of faecal matter from a bull!!!

        As this post points out, the conventional wisdom (i.e. what you have been taught and re-taught without question) is WRONG.

        Instead of trying to understand WHY this is different to what you have been taught, and instead of seeking new knowledge, you simply jump to the defence of what you already know!! What a poor standard of doctorate they now provide if you NEVER learn to ask whether the current knowledge is actually right!? That is the POINT of being educated, having the ability to question, not just defend what you already have in your head.

        Finally, the issue you and all your exercise and human physiology lecturers have failed to recognise is a few simple questions:

        1) If are bodies are incapable of utilising fat as an energy source (as is suggested here), and MUST have vast amount of carbohydrates in order to function – WHY did evolution for ALL animals choose fat storage as a survival mechanism? The human body, and that of most animals stores a pathetically small amount of glycogen (stored glucose for those unaware of the techno talk) in the muscles and the liver mostly. If we needed carbs to survive, ALL animals, including humans would have evolved a better and more capable glycogen storage system!!! This is just LOGIC – don’t need a masters or PhD to work that out!!!

        2) Again, if we NEED carbs to function, and especially the brain, then HOW did we evolve and grow most of the increases in human brain function during a period when we would have had LIMITED access to carbohydrates?? Prior to the utilisation of grains approx. 10,000 years ago (or at a stretch 30,000 for a single tribe as was recently discovered), there are little to no other significant sources of carbohydrate for the human species. By 50,000 years ago we had evolved way beyond apes and already had language, music, and other complex brain functions. HOW if what you say about carbs is true? ALSO how did we survive as a species in colder climates with limited access to even green leafy plants for significant portions of the year if we NEED carbs to function? We survived because proteins and fats and organ meats give us the necessary amino acids, vitamins, minerals and essential fats we need. The protein also provided a means for the liver to utilise gluconeogenisis to provide whatever carbs need we may have had in excess of the ketones our bodies and brains can use.

        3) If carbs are so good, why is it that since the advocation of high carb/low fat diets the rate of type 2 diabetes and obesity has skyrocketed? This is a FACT, look at the epidemiology data. In cultures where this was not advocated until later, the increases came later. This is NOT just due to lower levels of physical activity, as even in populations where physical activity has increased, the switch to higher carb diets has resulted in increased type 2 diabetes and obesity.

        Finally – The fact is insulin, which is not excessively excreted when there is less carbs in the diet PROMOTES fat storage in the body. This is one of the MAIN functions listed for insulin in almost ALL biochemistry and endocrinology texts. When insulin is present, fat cells are signalled to STORE fatty acids and convert glucose to fatty acids to store them. If you want anecdotal evidence of insulins weight promoting ability, ask ANY GP, endocrinologist, diabetes educator/nurse or diabetic. As SOON as someone is put on insulin, even if they exercise MORE than they did previously and eat less, they will put on weight. Of course it is HARD for them to eat less, as another problem with insulin is that it can OVERSHOOT the reduction in blood glucose, leading to hypoglycemia (blood glucose too LOW) which is at best dangerous, and worst this is FATAL. As a result, with blood glucose too low, the NATURAL response by the body to this problem is HUNGER (this is BASIC physiology – I trust you understand this – if you don’t HAND YOUR MASTERS back and save your money on your doctorate and go back to some 1st year biochemistry). As a result, the subsequent weight gain is an insidious cycle, as the insulin promotes fat storage of the calories consumed, and then lowers blood glucose, resulting in hunger and calorie consumption, and then the cycle repeats.

        IF you had actually WORKED with any type 2 diabetics, you would know that not all are just lazy as you suggest. Sure, some are, but here is the kicker, one of the effects of HYPERglycemia is lethargy, which leads to reduced caloric expenditure, which leads to higher levels of hyperglycemia.. again another twisted vicious cycle.

        Also recent research in Type 2 diabetes has demonstrated that regardless of blood glucose level, the use of insulin is associated with an increased risk of heart attack and stroke.

        OK, the real finally – the conventional wisdom that it is only overeating and laziness that causes type 2 diabetes and obesity is ignoring the fact that the energy systems (i.e. metabolic pathways and feedback loops) are not unidirectional. And this does take some understanding of thermodynamics (which I learnt in biochemistry – did they teach that in physiology?)… but the equation flows both ways.

        Gary Taubes has a great explanation of this, but essentially you are applying causation, when all you can observe is a relationship.

        If you say calories in = calories out is the equation then the equation works both way, i.e. calories out = calories in!

        So if you eat 2000 calories and then use 2000 calories you end up net zero. However it works the other way – if you USE 2000 calories, your body needs 2000 calories, and so it seeks 2000 calories. We know this is true, as people like Micheal Phelps eats many times the normal calories, due to the caloric expenditure he has. The calories USED DRIVES the calories consumed.

        Continuing, less calories in = less calories out, again in people that are starving, this is reflected in lethargy.

        So what about if you eat 2000 and you expend 2000 calories, BUT 200 (10%) calories you eat get stored and locked away before you can use them (and this is WHAT excess insulin does, it stores the calories BEFORE they can be used – it lock away fatty acids). Now you have used 200 calories more than you have available, your body has TWO possible responses:

        1) Eat 200 calories more (with 20 (10%) stored like before), so you need another 20, with 2 stored, so you need another 2 – all up an extra 222.2 calories consumed, with 222 stored as fat. This manifests in the “real world” as someone “overeating”

        OR

        2) you reduce your energy expenditure to 1800 (with the 200 still stored as fat). This is deemed in the “real world” as someone becoming less active or sedentary.

        In this way it is possible that fat storage leads to lethargy and overeating.

        You CANNOT say calories in = calories out and accept that as fact, but then refuse to acknowledge that in a biological system that has feedback loops for survival that the reverse is not ALSO true, i.e. the amount of calories used is related to the amount of calories consumed, and the amount of calories that can be used, is also affected by how many are available. If you cannot access the calories, because the excess insulin has caused storage then it is entirely logical that this will result in either lethargy and/or excessive consumption of calories.

        You are basing your entire arguments on what you have been taught, yet simple logic, basic biochemistry, endocrinology and thermodynamics demonstrate that your arguments are lacking in basis in simple facts, and are only supported by your belief that because someone with an academic degree taught you it whilst you obtained the same academic degree they must be true.

        Start using that overeducated brain of yours and apply the scientific method of investigation and query to this stuff and whilst you may find you wasted tens of thousand of dollars on the facts your were taught during your education, at least those tens of thousands of dollars would have amounted to something, by equipping you with you skills and knowledge to challenge the status quo and forge ahead with new lines of thinking and insight. Again, some of the top, scientists, cardiologists, endocrinologists, biochemists and even exercise physiologists in the world are recognising this – go on, back yourself to be ahead of the scientific herd, trust me NO great scientist just accepted what he or she was taught!!!

        Luke wrote on May 31st, 2011
        • Please excuse typos – was just belting this long post out… notable errors (there is likely more):

          “I invoke me degrees in…” should be “I invoke my degrees in…” (always dangerous editing “let me” into something else on the fly)

          “If are bodies are…” whoa – one too many are’s and one few on the our’s… Should be “If our bodies are…”

          Luke wrote on May 31st, 2011
        • Again, my point is that it is wrong to think that the body is designed to rely solely on protein as a source for glucose (gluconeogenesis). This is the claim that the author of this article is making. My point in response to others is that carbohydrate is not toxic, and that it is important for the body, particularly the brain.

          To reiterate my point, inadequate amounts of carbohydrate intake is not advantageous for the brain. I did not say that an excessive amount of carbohydrate intake is okay. I did not say that our bodies don’t need adequate amounts of fat and protein. Our bodies do not function optimally with zero carbohydrate intake. I think anyone would agree that humans evolved eating vegetables and fruits (plenty of carbohydrate), along with other sources of protein and fat.

          I reveal my education status only to show that I’m not some schmuck posting random stuff, not because I think I’m smarter than everyone.

          I understand the role of liver, gluconeogenesis, and the cycle of proteins to carbohydrate, and carbohydrate to fat, etc. As a biochemist, certainly you understand that protein conversion to carbohydrate in the liver also produces ammonia. If the body were to rely solely on protein in for gluconeogenesis, due to a lack of carbohydrate intake, this would obviously become problematic. Excessive cycling of the urea cycle would cause a protein imbalance.

          I did not say that our bodies are “incapable of utilizing fat as an energy source.” I did not say that our bodies “MUST have vast amounts of carbohydrate in order to function.” I’m saying that our brains need an adequate amount for optimal function.

          Also, the major causes of death of type 2 diabetics are heart attack and stroke. You can get this information from the CDC. Of course, chronic hyperglycemia initiates the disease state. The point is that you will not typically see “hyperglycemia” on the death certificate of a type 2 diabetic.

          Seth wrote on May 31st, 2011
        • I will admit that the type 1 diabetic “experiment” isn’t appropriate. It doesn’t address the authors point.

          Seth wrote on May 31st, 2011
  15. OK, let me walk you through this one step at a time – What CAUSES heart attack and stroke in T2 Diabetics?

    Bill DeWitt wrote on May 31st, 2011
    • Bill,

      EXACTLY!!!

      I worry about the academic integrity of the current university system if people with masters that are studying doctorates cannot understand the difference between a cause and an effect!!!

      I guess this whole Seth thing proves what we already know – busting the conventional wisdom is going to take a long time, when even the (so called/self professed) best and brightest science graduates are so indoctrinated and brainwashed to the point they abandon all scientific curiosity and leap to the defence of what they have been taught, rather than seeking to understand a bit more about a different point of view.

      I wish I wasn’t travelling, I would have love to have dosed up the references and also written something a little less stream of consciousness.

      However as your next post states, this guy thinks he knows everything already, so no doubt I wasted my time… or perhaps not, perhaps someone with a true scientific mind of curiosity and interest will read it and take a new perspective from it!?

      Luke wrote on May 31st, 2011
      • I do believe that a restricted calorie diet is the most healthy choice. My point is that the body does not function optimally in starvation mode, and that constant gluconeogenesis without any carbohydrate intake is not a normal and healthy state for the body.

        Seth wrote on May 31st, 2011
        • “I do believe that a restricted calorie diet is the most healthy choice. My point is that the body does not function optimally in starvation mode,”

          Ummm really, restricted calories is good, but starvation is bad!!!

          Make up your mind!

          The author does not say to eat ZERO carbs (look at the information), so you are arguing about nothing… grow up.

          OK, now you must cite your sources!!!

          “constant gluconeogenesis without any carbohydrate intake is not a normal and healthy state for the body.”

          Where is your source for this?

          Explain Inuit populations, or other populations in Africa that do not eat carbs?

          Explain how we as a species survived ice ages?

          Just because it is not what you are used to, does not mean you can make a claim like this!?

          Again I ask, if the lack of carbohydrate is SO BAD for a human body (or that of any mammal), WHY did we evolve with such a WOEFULLY inadequate glycogen storage system???? You MUST be able to explain this.

          Evolution by natural selection MEANS that if this was absolutely necessary, we would have evolved a better glucose storage system – PERIOD.

          We didn’t evolve this system, because it DOES NOT MATTER or do harm to a human body to be in a state without exogenous glucose from carbs.

          We CAN and do have a system for creating glucose in the body, we do not for certain fatty acids (i.e. fats) and certain amino acids (i.e. proteins)… You JUST IGNORE this, because you have ho answer.

          Cite YOUR sources to make such an outrageous claim that living without a carbohydrate intake is not normal or healthy, when the evolution of the entire animal kingdom demonstrates otherwise.

          Luke wrote on May 31st, 2011
    • “I think anyone would agree that humans evolved eating vegetables and fruits (plenty of carbohydrate), along with other sources of protein and fat.”

      SOURCE PLEASE!?

      1) Vegetables are NOT a plentiful sources of carbs.

      2) And unlike your pampered existence, fruits are seasonal. You are applying your 21st century understanding of the food chain to our human evolution.

      Fruits don’t become fruit all year round. So they were limited to when available. Just because you can walk into a Whole Foods and buy fruits at any time of the year does not mean that is how we evolved – seriously – you have a masters and are getting a doctorate?!

      3) The fruits we most commonly ate were berries, we also ate nuts. We lost our ability to climb, so we in essence ceded fruits high in trees to our ape cousins until we worked out tools to get them down. Berries are NOT high in carbs (relatively)

      “If the body were to rely solely on protein in for gluconeogenesis, due to a lack of carbohydrate intake, this would obviously become problematic. Excessive cycling of the urea cycle would cause a protein imbalance”

      What are you doing – just arguing to show how smart you are?! NOT ONCE in any part of this site does the author EVER suggest NO carbohydrates – EVER, so your point is irrelevant (and revisionist).

      The author recommends berries (is not so keen on bananas as they are VERY high in carbs), and does recommend fruit. Mark (sorry over calling him the author), advocates MOSTLY green leafy things as the basis of the dietary recommendations (by the way the Primal Blueprint is MORE than a diet – you wouldn’t know this, because you are just arguing, telling us we are so misinformed, without checking what is actually being recommended – which is worse misinformed, or just uninformed?!)

      “I’m saying that our brains need an adequate amount for optimal function.”

      CITE YOUR SOURCE!!!

      I don’t have the references with me, but in well designed tests where those on ketogenic diets were compared to those on regular diets the cognitive functions were equal. The only studies where this isn’t these case have a design flaw. If you switch from a carb heavy diet to a low carb diet, then it is a KNOWN fact that it takes up to two weeks for the body to get back into full swing burning fats. So if you do a test where you take high carbers (and that means people that eat pasta, bread and rice) and then switch them to low carb and test them immediately, they will do worse.

      This fact supports the theory that we evolved with very low carbs in our diet.

      If we did have high carbs and each time we ran out (which would have happened often in prehistoric past human life) and it took weeks to get back to optimum, then we would have evolved to not have that lag (because being impaired in this way would put you at risk, and those that switched quickly would have had a survival advantage).

      The fact this lag persists to today means we DID not have high carb diets that then resulted in us having a lag in switching back to low carb. We just were low carb most, if not all the time.

      We then rarely got some carbs, but this did not occur for so long that we needed to “switch back to low carb” and adjust.

      I mean this is SIMPLE deduction using evolutionary theory.

      “Also, the major causes of death of type 2 diabetics are heart attack and stroke. You can get this information from the CDC. Of course, chronic hyperglycemia initiates the disease state. The point is that you will not typically see “hyperglycemia” on the death certificate of a type 2 diabetic.”

      And who said that hyperglycemia is the cause listed on the death certificates of type 2 diabetics?!

      You are being revisionist here… you are trying to weasel out of the fact that you made this stupid statement!

      The previous poster stated:

      “hyperglycemia is one of the major causes of the eventual death of T2 Diabetics”.

      Whilst this is not perfect stated, only someone trying to be a smart arse would try and say that this post was suggesting that hyperglycemia is what is listed in the death certificate.

      There you go again with the use of “higher authority” by calling on the CDC… WHY?

      In my answer I stated:

      “The damage to the vascular system, including the regulation of blood pressure by the kidneys is damaged by CHRONIC hyperglycemia. As a result after YEARS of elevated blood glucose (hyperglycemia) the damage to the vascular system results in heart attacks and strokes.”

      Clearly I am aware that heart attacks and strokes are the listed cause of death, but the cause of the heart attack and strokes is hyperglycemia – FACT, don’t need the CDC, I have worked in the area, and you were being smug in your original post and now are trying to say you were just misunderstood.

      Luke wrote on May 31st, 2011
  16. No, you know what, never mind. Since you refuse to look up the recent information on the subject, you are not interested in learning. You believe you already know everything. Good luck in your future endeavors.

    Bill DeWitt wrote on May 31st, 2011
    • I don’t think I know everything. I’m saying that I do know what hyperglycemia is and that I don’t need to look it up.

      Seth wrote on May 31st, 2011
  17. Luke, thanks for taking the time to write all that. I Had to laugh at the “bad diet and no exercise” myth, since I grew most of my own food, ate nothing but whole fruits, vegetables and “healthy grains”, and worked out 4 days a week with a trainer, and ran the other three days. I ate better and exercised more than the average human, but the excess amount of carbs in my diet caused (surprise!) an excess of carbs in my blood! Now, I have cut back the dietary carbs to a metabolically insignificant amount, and (double surprise!) have had 10 years of rock stable BG readings. I am so sure I am going to listen to some guy on the internet who claims to have studied something as opposed to the many practicing cardiologists, PHD biochemists, and long term successful T2 Diabetics. I happen to be working on an advanced degree in Biochemistry and I can already point to the many mistakes in basic assumptions in my text books. I just learn it the way they tell me and wait until I can be the one writing the books and teaching the classes.

    Bill DeWitt wrote on May 31st, 2011
    • A poor diet that includes excessive calorie intake, and no regular exercise, does lead to chronic hyperglycemia type 2 diabetes. Type 2 diabetes is typically reversible with calorie restriction (a balanced diet) and/or exercise.

      I’m trying to put together what you’re saying, and it sounds like you’re saying that eating only fruits, vegetables and grains, and exercising 7 days a week caused blood glucose levels of 700. That obviously doesn’t sound right. Please clarify, or at least tell the whole story.

      Seth wrote on May 31st, 2011
    • Haha – gold… let me know when you publish, I’ll buy that book!!!

      However I assume you mean a text for physiology, as in biochemistry texts, all the basic information is already there!!!

      At least when I was studying, they described the pathways etc (without the dogma of fats are bad/carbs are good/proteins are depends on who you ask), then it is clear that the human biochemical pathways (and in fact mammalian biochemical pathways) favour fatty acid utilisation in a great number of situations.

      The hormonal function of insulin is clear, it allows glucose transport into cells and promotes fatty acid biosynthesis from carbs and fatty acid storage in the fat cells. In the absence of insulin this process is reversed. The hormone glucagon (essentially “anti-insulin”) promotes the reverse process (i.e. breakdown of fatty acids for use as energy and the release of fats from fat cells). These are not debatable – these are biochemical FACTS.

      Additionally Glucagon signals the liver release glucose into the blood stream and promotes gluconeogenisis from amino acids. Glucagon is suppressed by the release of insulin.

      The consumption of ANY food releases insulin (and down regulates as a result Glucagon), however the presence of carbohydrates (particularly refined carbs and fructose) result in a significant spike in insulin, and a subsequent drop, which can induce hunger. Fats and proteins are more slowly absorbed, and as a result do not invoke such a large insulin spike. As a result glucagon is able to produce glucose if needed, and with the lower insulin levels fatty acid oxidisation (i.e. fats as fuel) is able to occur.

      Again these are facts of biochemistry.

      Based on these facts of biochemistry the worst meals in terms of weight gain are:

      1) high fat & high carbs. Huge insulin spike, fats shuttled into fat storage AS WELL AS THE carbs converted into fatty acids for further fat storage. Stored fats not available for use (high insulin levels lock it in – and promote insulin resistance too), meaning you feel hungry for calories to make up the shortfall between the amount available from your meal and what you are using, so you EAT more than you would normally to get the SAME amount of available calories for your body to use. Worse still, high insulin spike results in HUGE blood glucose drop (carbs stored as fat and what is left is rapidly used), resulting in low blood glucose, leading to feelings of hunger. With the combination of stored calories and blood glucose drops, even if you manage to ignore your hunger and hot eat, you end up with feelings of lethargy, as you have less energy available, especially when insulin resistance develops due to the excessively high insulin levels, because even if you eat more, your muscles now can’t absorb the energy. High carb and high fat meals are a double whammy!!! Biochemistry facts, don’t need a masters of PhD to work this stuff out

      2) High carb low fat meals (but still high in calories). Pretty much the same as above, except you wont store as MUCH fat (less to directly store), but still some carbs get converted due to high insulin. Same result in less available calories, so need to eat more, similar Blood Glucose crash, so similar feelings of hunger. High insulin levels also result in insulin resistance, with subsequent weight gain, reinforcing insulin resistance and also the lethargy cycle described above.

      3) Just and average mix of all three nutrients. with enough exercise you may avoid weight gain for some time. Likely to result in slow insidious weight gain that creeps up over 5-10 years, eventually tipping the system enough to result in a rapid weight gain and perhaps some pre-diabetic symptoms. You believe the exercise physiologists of the world and cut out some fat from your diet (and end up at point #2 above!!!)

      4) Primal/paleo approach. Mid-level carbs (not low carbs), moderate protein and high/er fat. Moderate insulin response, with possibly glucagon available if needed. Insulin levels are such that fat storage is minimised if at all present, however fat release is not promoted either. Weight is maintained easily. Energy levels are fine, as amount consumed = amount available, and also lower insulin levels and body weight in normal range means little if any insulin resistance.

      5) Primal/low carb. Lower carb level, moderate protein and high fats – only when seeking to lose weight. Very low insulin response. Absence of carbs in diet promotes glucogon release and gluconegenisis. This triggers fatty acid release from fat cells, fatty acid oxidisation and ketones do form. Energy pouring out of fat cells, results in increased available energy, so eating less calories is easier, without hunger, and still meeting calorie expenditure needs. Once you reach your target weight, you up the carbs to kill off ketosis and jump back up to #4 above to maintain weight.

      All of this makes biochemical (and endocrinological) sense. It is consistent with known biochemical pathway and hormonal systems understanding and facts.

      The alternative that you can eat like #2 and lose weight is bullshit… only way is to cut calories or up exercise, which most people can’t maintain due to resulting hunger and lack of available energy (insulin levels still promoting storage if possible) – granted excessive deficits will result in fat being released – but inefficient and sadistic way to lose weight compared to #5/#4 which are biochemically and hormonally the easiest way to do it.

      Of course those that build their living on people needing to be cajoled/hounded/berated by a personal trainer or dietician has a significant conflict of interest in accepting anything but approach #2, as it is the approach that maximises the need for their services!!!

      That is why I have left pharmaceuticals. After discovering MDA, Primal Blueprint and all the other information I have researched in scientific papers and textbooks since, I realised that that industry, whilst it did not create this myth of how to lose weight, it is profiting from this awful error in human understanding. So now I spend my time ripping apart the flawed logic in those still clinging to conventional wisdom… of course working in pharmaceuticals I was trained on how to promote conventional wisdom and confuse others when they noticed it’s flaws (Seth used the most common used by pharma – the “higher authority/academic backing” card)… with that knowledge I find it easy to pick the blatant holes in their arguments and point them out for the fallacies that they are… Hopefully I can use that to help a few people see that conventional wisdom, and hence medicine and health authorities have bet the collective health of the human race on a flawed premise about human metabolism…

      Cheers,

      Luke

      Luke wrote on May 31st, 2011
      • I’m in agreement with this.

        What blatant holes are there in my argument? The author of this article insists that we don’t need to consume carbohydrate because the liver creates all the carbohydrate we need. Yes, the liver can produce carbohydrate, but overall this is a misunderstanding. The author has taken a know piece of biochemistry and has spun it out of control.

        I list my academic achievements to make the point that I have formal education.

        For the record, I’m not a personal trainer, or work in any industry, or cling to any “conventional wisdom.” I’m an extreme opposite. The incorrect “conventional wisdom” out there appears to be that diet and metabolism must be incredibly complicated, and that there’s some secret to eating well and losing weight. For example, the author of this article suggests that we all need to completely do away with carbohydrates because he/she heard about gluconeogenesis in the liver. That’s great if one wants to lose weight, but it’s not sustainable.

        Again, what you typed about the body’s biochemistry and physiology is basically correct. But I’m not sure what your point is and how it relates to the author’s article.

        Seth wrote on May 31st, 2011
        • Again – you have decided to argue, without checking your facts.

          1) The author (Mark) actually advocates eating is easy, his easy just limits carbs by excluding grains. You are hung up that your easy is the right easy.

          2) Repeated studies and empirical evidence show that restricted calorie diets are NOT easy and as a result FAIL, again and again and again.

          3) The Author (Mark) NEVER, not ONCE stated to eat no carbs… you are misleading stating this:

          Let me copy the text here, if it is TOO hard for you to scroll to the top of the page and read it:

          “So How Much Glucose Do You Really Need?

          Much less than most people assume. At any one time, the total amount of glucose dissolved in the bloodstream of a healthy non-diabetic is equivalent to only a teaspoon (maybe 5 grams). Much more than that is toxic; much less than that and you pass out. That’s not much range for a so-called “preferred” fuel, is it? Several studies have shown that under normal low MET conditions (at rest or low-to mid- levels of activity such as walking and easy work) the body only needs about 5 grams of glucose an hour. And that’s for people who aren’t yet fat-adapted or keto-adapted. The brain is the major consumer of glucose, needing maybe 120 grams a day in people who aren’t yet on a low carb eating program. Low carb eating reduces the brain’s glucose requirements considerably, and those who are very low carb (VLC) and keto-adapted may only require about 30 grams of glucose per day to fuel the brain (and little-to-none to fuel the muscles at <75% max efforts). Twenty of those grams can come from glycerol (a byproduct of fat metabolism) and the balance from gluconeogenesis in the liver (which can actually make up to a whopping 150 grams a day if you haven’t metabolically damaged it with NAFLD through fructose overdosing). Bottom line, unless you are a physical laborer or are training (exercising) hard on a daily basis, once you become fat-adapted, you probably don’t ever need to consume more than 150 grams of dietary carbs – and you can probably thrive on far less. Many PBers do very well (including working out) on 30-70 grams a day."

          Where is the ZERO?

          Mark even includes a GRAPH (pictures are easy aren't they?) that shows that he has three zones with 100-150 being effortless weight maintenance, 50-100 effortless weight loss and <50 Ketosis / intermittent fasting…

          "the author of this article suggests that we all need to completely do away with carbohydrates because he/she heard about gluconeogenesis in the liver. That’s great if one wants to lose weight, but it’s not sustainable."

          I call BS…

          This guy hasn't just heard about gluconeogenisis in the liver… I'm not going to bother to do your intellectual works for your, go and read about him AND HIS qualifications, seeing that is all that matters to you!!!

          Secondly ALL the information he gives states that the lower levels are for weight loss, and that the sustainable level is between 100-150.

          This is in EXCESS of the daily requirements of the human brain, and is above ketosis – did you EVEN READ this article before deciding to attack it from your pseudo-intellectual ivory tower?

          "A poor diet that includes excessive calorie intake, and no regular exercise, does lead to chronic hyperglycemia type 2 diabetes."

          True – but what you have now done is state a fact, and inferred that means everything else you have said is therefore right.

          You have YET to identify (let alone cite) a substantial reason that this approach that Mark writes is not a healthy diet. Your reasons are based on FALSE assumptions of what he has said. You even assume he means no fruit or veg, yet if you read his recommendations, you would see that veg are the basis of his food pyramid and many fruits (not all) are part of the recommendations too. He also has an 80% rule, which is follow it at least 80% of the time and don't obsess over things if you stray, as he firmly believes that people make it all too complicated.

          "Type 2 diabetes is typically reversible with calorie restriction (a balanced diet) and/or exercise"

          For as long as the calorie restriction lasts. A ketogenic diet has repeatedly been shown to be the most effective at reversing type 2 diabetes. There are papers galore on this, and I have also witnessed it with living breathing type 2 diabetics.

          The low fat high carb approach (even the whole low GI thing) is torturous for the reasons I outlined in the post that described the diet approaches. You ask them to exercise, and yet you give them a diet that does not allow them to maximise energy expenditure.

          A Ketogenic diet opens the fats cells to releasing fats – this is a biological/biochemical/endocrinological FACT… it is backed up by the reports from both diabetics and non-diabetics that adopt these diets that they feel like they are almost bursting with energy… well this is almost quite literally true… the now released fatty acids from their fat cells provide so much energy to them, that they can reduce caloric intake without feeling hungry (the body doesn't send hunger signals when it is bathing in energy) and they also have enough energy and reduced lethargy to exercise.

          You AGAIN are assuming that the equation is one way… I can't explain it any easier… go read up about it.

          The storage of energy from the diet as fat (due to hugh insulin) traps this energy, making it unavailable for use, and hence increases appetite or reduces energy expenditure. Either way the result is less movement with weight gain, or more eating with even more weight gain, most often BOTH.

          You then observe this and state it is the eating and reduced movement that causes fat storage, instead of realising that it can also be the fat storage that causes increased eating and reduced movement – IT WORKS BOTH WAYS.

          Yes it is true some people eat too much, but again, biochemically, eating carbs increases your chances of an insulin spike and then crash, which makes you more likely to feel hunger again. Again this is born out in studies and from real life experience.

          Eat a pasta meal for and you are SURE to be hungry when you wake up (sometime even before bed).

          Eat a protein and fat meal and you can even skip the next meal if you want. Repeated studies show satiety with proteins and fats FAR outstrips carbs, especially calorie for calorie.

          So whilst this is true, it doesn't mean it is the ONLY truth.

          "Type 2 diabetes is typically reversible with calorie restriction (a balanced diet) and/or exercise"

          It is also reversible with a reduction of carbs by eliminating grains (still eating veg and lower carb fruits) and/or exercise. And it doesn't result in hunger, and the foods are generally more enjoyable to eat.

          This I have witnessed with my own eyes. The second approach which is diets #4 and #5 (in my previous post) are much better than #3 – which is what you advocate.

          You have NEVER tried it, let alone understand it, yet you reject it.

          Spend some time reading through this site – you will see this is NOT a no carb site.

          The point is we don't need to eat as many carbs as is typically done (even without going into ketosis) – and this is backed up by science.

          Luke wrote on May 31st, 2011
      • Actually, after reading and thinking about this article more, I’m in agreement. And yes, I mistakenly jumped to some conclusions. He doesn’t say no carbs.

        However, I still have a problem with some of the author’s comments, which are reasons why I first posted:

        “… and the brain can run just fine (maybe even optimally) on a blend of ketones and minimal glucose. . . Entire civilizations have existed for ages on what is practically a zero-carb diet.”

        I don’t think it’s correct, and I would like to find sources that back this up.

        Seth wrote on May 31st, 2011
        • Seth,

          I have to acknowledge 2 things:

          1) You are a better man than most. May people argue their position, and wont budge, no matter what the evidence. Even more so for people that post on blogs etc… Have to say well done mate (and please do not take that as patronising, I sincerely mean it).

          2) I was a bit of a dick last night (well last night as far as the time zone I am in). I have been travelling for work, and was jet lagged, and clearly in a foul mood.

          This does not excuse some of the things I said in debating you, in particular the amount of ad hominem statements I made… poor form on my part and intellectually weak…. Argue the points/topic, don’t attack the person, I apologise for my snide remarks – no excuse.

          Regarding your remaining doubts about the following statement:

          “… and the brain can run just fine (maybe even optimally) on a blend of ketones and minimal glucose. . . Entire civilizations have existed for ages on what is practically a zero-carb diet.”

          Again I do not have references on hand, however a few things:

          1) Civilisations have existed for ages on what is practically a zero-carb diet. Inuits, various tribes, and significant portion of our entire species during the ice ages. This is documented.

          2) “and the brain can run just fine (maybe even optimally) on a blend of ketones and minimal glucose…”

          Again, there are sources to back that the brain can run just fine on a blend of ketones and minimal glucose… the key here being the use of the word minimal… minimal is definitely above zero, probably around 80-100g of carbs per day, but not much more than around 150g carbs per day for MOST people (naturally exceptions are always present). This is significantly less than what the typical diet would consume, especially if you eat wheat, corn or rice products. I would encourage you to do a search using the search function on this site. Mark will likely have a post specifically on carbs, and he will cite references many times. This post was a summary of a number of different concepts he has written about over many years.

          This leaves “(maybe even optimally)”… This is Mark’s view. He does not the brain DOES run optimally, he states it MAY run optimally. MAY is the universal qualifier. Whenever you see it, you can safely assume there is no specific evidence to be cited. It does not mean it doesn’t exist, it just means it isn’t being used.

          This is a problem when you read/hear/watch most news bulletins these days, to avoid doing REAL journalistic investigation, they just say “may”, “perhaps”, “suspected”… all these words allow you to say what ever you want, without a shred of evidence.

          “We may all die tomorrow”… UNLIKELY, but logically true, as we MAY all die tomorrow, no way of knowing.

          “X X may run for President”… again – 100% true, no matter how likely.

          If I wasn’t travelling I’d take the time to find some evidence, as I am certain I have read it somewhere.

          You may ask, but you defend this dietary approach, how come you are unsure?

          Simple – For all the biochemical and evolutionary reasons I have stated, and results I have witnessed with my own eyes, I know the elimination of carbs from grains and increased consumption of fats is NOT the health issue many state.

          I also know you can function on reduced carb consumption, both physically and mentally.

          To me, whether you perform better, is irrelevant. Likewise, even if it isn’t perfect, I know it works.

          However finally, I am a fanatic when it comes to the power of evolutionary pressures, and quite simply when you apply evolution to the problem, the fact remains, that as a species we MUST do at least as well, if not better with very low carb consumption, because until we learnt how to mill wheat, rice and corn and then COOK it (which was only ~ 10,000 years ago), the VAST majority of the human race just DID NOT HAVE access to that many carbs and so without having a choice, lived a VERY low carb diet. Add the selection pressures of an ice age (when the ability to survive on near zero carbs would have been selected for) and also the “thought experiment” I described about how the switching from high to low carb results in a lag in switching back to a low carb system SUPPORTS the fact we evolved not having ready access to lots of carbs (otherwise that lag would have been selected out) then I just cannot see how we CANNOT thrive on a low carb diet – evolution has selected us for that, and biochemistry provides all the proof to show fat is the preferred fuel source.

          And finally (there is always a finally) – our vast ability to store fat (actually I missed this in Mark’s post above, I independently came to the same conclusion as he has), and PALTRY ability to store carbs. If carbs are SO important for optimal function we would have evolved to preferentially store them – NOT fat.

          Anyway – all I can suggest is you explore this site more. As I said search for certain topics for more in depth posts (and perhaps use the menu system on the top to find topics).

          All the best with the exploration…

          Luke wrote on June 1st, 2011
        • Regarding your statement, “If carbs are SO important for optimal function we would have evolved to preferentially store them – NOT fat.”

          I can understand why one would believe this to be evidence for preferential use of fat by the body. However, it’s misleading. The reason animals have evolved to store calories in the form of fat is because adipose (fat) contains very little water compared to stores of glucose (glycogen). For every gram of glycogen, there’s something on the order of 3-4 grams of water with it. We evolved to store energy as fat simply because it’s a very efficient calorie storage mechanism. This mechanism allows animals to not have to carry heavy stores of energy. And it follows that there’s a relatively large amount of energy that is released when these long hydrocarbon chains are oxidized. I don’t think it’s accurate to say that energy is stored as fat because the body prefers to utilize fat. I think it would be more accurate to say that the body utilizes relatively large amounts of fat at REST because the demands for energy are less (creating time for the enzymatic events in beta oxidation, the krebs cycle, and oxidative phosphorylation). Although large amounts of energy are released, due to the efficient storage of this energy, it’s sluggish compared to glycolysis. I just can’t make an argument that the body prefers fat, mainly because the brain does not utilize fat. Most physiological processes in the body (e.g., cardiovascular, metabolic, etc.) function so as to serve the brain first.

          Seth wrote on June 1st, 2011
        • So far, the data doesn’t support this.

          Br J Nutr. 2010 Dec;104(11):1666-87. Epub 2010 Sep 23.

          Estimated macronutrient and fatty acid intakes from an East African Paleolithic diet.

          http://www.ncbi.nlm.nih.gov/pubmed/20860883

          “We found (range of medians in en%) intakes of moderate-to-high protein (25-29), moderate-to-high fat (30-39) and moderate carbohydrates (39-40).”

          Seth wrote on June 1st, 2011
        • Furthermore, why would the contents of human milk (1.1% protein, 4.2% fat, 7.0% lactose) be so different?

          Seth wrote on June 1st, 2011
        • I agree that our primitive ancestors probably consumed less carbohydrate than modern Americans, for example. And I also agree that our primitive ancestors, and modern humans, prefer fats over carbohydrate (I also agree that a ketogenic diet my be healthy in some respects for the brain, based on some interesting research articles I read today). However, our best estimates of a primitive diet does not reflect fat intake exceeding carbohydrate intake. If carbohydrate were limited to what is suggested here, and according to what you say (“minimal is definitely above zero, probably around 80-100g of carbs per day, but not much more than around 150g carbs per day for MOST people”) the rest of the daily requirements just for resting metabolic function (1600 kcal, for example) would have to be made up in large proportion in fat and protein. 100 grams of carbohydrate is only 400 kcal. Healthy, daily activity would about double the required calorie intake. This paradigm (100-150 grams carbo) seems to be okay just to meet resting metabolic needs (or to lose weight), but remember that our primitive ancestors were also distance runners! There’s has to be room for calorie intake for physical activity.

          The research article below suggests that protein intake often takes place of carbohydrate intake in hunter-gather diets, but that the proportion of fat or protein intake probably doesn’t exceed carbohydrate intake.

          Am J Clin Nutr. 2000 Mar;71(3):682-92.

          http://www.ncbi.nlm.nih.gov/pubmed/10702160

          Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets.

          “This high reliance on animal-based foods coupled with the relatively low carbohydrate content of wild plant foods produces universally characteristic macronutrient consumption ratios in which protein is elevated (19-35% of energy) at the expense of carbohydrates (22-40% of energy).”

          Seth wrote on June 1st, 2011
        • Okay, I’m more in agreement now, considering the research article below:

          Am J Clin Nutr. 2000 Mar;71(3):682-92.

          Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets.

          http://www.ncbi.nlm.nih.gov/pubmed/10702160

          “Our macronutrient projections for worldwide hunter-gatherer diets indicate that these diets would be extremely high in protein (19–35% of energy) and low in carbohydrate (22–40% of energy) by normal Western standards, whereas the fat intake would be comparable or higher (28–58% of energy) than values currently consumed in modern, industrialized societies.”

          Seth wrote on June 1st, 2011
      • “However I assume you mean a text for physiology, as in biochemistry texts, all the basic information is already there!!!”

        All the information is there, and then they simply ignore that information to express assumptions which are contra-indicated by their own data. (Paraphrase) “Insulin controls the level of blood glucose by opening the transport proteins which leads to the glucose binding to fatty acids which cannot leave unless glucagon releases the glucose from the cell. But obesity is actually caused by eating a poor diet and not exercising enough.” It’s like a disconnect between their information and their ability to think, probably caused by having heard the lie so often. I have marked this kind of false interpretation of the data in my Physiology books, my basic biology book, and even in both psychology books so far. It was presented without the biochemical info in my last math book and I know I am going to run into it in my “Human Ecology” class. I even had to sit through my language instructor’s lecture about it, as if it had anything to do with APA citation guidlines.

        The facts are all there (as in Mark’s article), but many people simply cannot see them because their assumptions are smack in the way.

        Bill DeWitt wrote on May 31st, 2011
        • Hey Bill,

          Yeah you are right… I likely have forgotten the finer details like the throw away comments… I will admit it was some time ago I was at Uni.

          Good luck with the studies and as I said, I look forward to reading Biochemistry Essentials by B. DeWitt!!! :-)

          Luke wrote on June 1st, 2011
  18. JAMA. 2003 Apr 9;289(14):1837-50.

    http://www.ncbi.nlm.nih.gov/pubmed/12684364

    Efficacy and safety of low-carbohydrate diets: a systematic review.

    DATA SOURCES:

    We performed MEDLINE and bibliographic searches for English-language studies published between January 1, 1966, and February 15, 2003, with key words such as low carbohydrate, ketogenic, and diet.

    CONCLUSIONS:

    There is insufficient evidence to make recommendations for or against the use of low-carbohydrate diets, particularly among participants older than age 50 years, for use longer than 90 days, or for diets of 20 g/d or less of carbohydrates. Among the published studies, participant weight loss while using low-carbohydrate diets was principally associated with decreased caloric intake and increased diet duration but not with reduced carbohydrate content.

    Seth wrote on June 1st, 2011
    • “There is insufficient evidence to make recommendations for or against the use of low-carbohydrate diets”

      Yup. One of the fundamental laws of real science is that if you refuse to ask the right questions, the answers you get are meaningless. Even if they are correct. What passes for science in the field of nutrition is mostly superstition. Low-carb diets are simply NOT STUDIED, or if they are, it is invariably using partially hydrogenated corn oil as the main source of fat (e.g. http://www.ncbi.nlm.nih.gov/pubmed/21321316).

      OTOH, I have yet to see a study in which dietary carbohydrate was reduced, even slightly, that did not produce health improvements. Although said improvements are *ALWAYS* attributed to something other than the carbohydrate reduction.

      Howard wrote on June 1st, 2011
    • OK Seth,

      Lot’s to consider from your posts:

      Firstly:

      “I can understand why one would believe this to be evidence for preferential use of fat by the body. However, it’s misleading. The reason animals have evolved to store calories in the form of fat is because adipose (fat) contains very little water compared to stores of glucose (glycogen). For every gram of glycogen, there’s something on the order of 3-4 grams of water with it. We evolved to store energy as fat simply because it’s a very efficient calorie storage mechanism….I don’t think it’s accurate to say that energy is stored as fat because the body prefers to utilize fat….”

      I was kinda hoping you would take this approach to defend the lack of glycogen storage due to water storage requirements AND energy efficiency. This observation on your part allows evolutionary pressures (my thing remember) to come into their own.

      AGREED – you cannot conclusively state that “that energy is stored as fat because the body prefers to utilize fat”, however that does not mean you cannot hypothesise the following:

      What you have just stated is that the organism (i.e. animals including humans) prefers fat storage due to the fact that carbs require significantly more water to be stored with them AND fat is a more energy dense nutrient.

      So, why do you assume that evolution works in only ONE direction? By the VERY fact that carb storage is inefficient and cumbersome due to water storage needs, this would provide SELECTION pressures for the organism (ALL of them) to FAVOUR fatty acid metabolism.

      Due to the fact that you SO ELOQUENTLY and emphatically NAIL the final nail in the coffin for carbs as an energy source – i.e. they SUCK as an energy for storage for an living organism, then the organisms that developed EFFICIENT metabolisms for the energy source that IS EASILY stored would prosper when food was scarce etc, which happened often before we humans worked out how to used OIL energy to counter nature (fertilisers, pesticides and intensive farming ALL rely on oil energy – without it, we cannot feed the population)

      You have just provided the VERY reason that fats are a preferred energy source, because over MILLIONS of years of evolution (even before we were humans) we (and all other animals) evolved with a selection pressure for efficient use of the energy source that is most EASILY stored – FATS

      NOW in anticipation of your (and probably others reading this) chomping at the bit for all the “VEGETARIAN” animals, I have the trump card for you.

      Let me quote from a great website I found on the subject (written by a PhD no less!!!):

      “No mammal — not even the herbivores — has developed an enzyme that will digest vegetable fibre. This is why we tend to discount it when calculating our calorie intakes. However, while mammals have not developed an enzyme that will digest fibre, there are lots of micro-organisms and bacteria that can the job for them. The herbivores employ billions of these bacteria.”

      “In a herbivore such as the gorilla, the caecum and colon harbour huge colonies of bacteria which ferment carbohydrates, particularly fibre, and use it to produce short chain fatty acids (SCFA) — principally acetic, proprionic and butyric acids. These are then absorbed into the body to be used as a source of energy.

      If we look at the gorilla’s diet, we now see that the authors of the study into the western lowland gorilla’s diet find that the fibre provides some 1.5 kcals of energy per gram of fibre, in the form of SCFA. As the fibre averages about three-fourths of the gorilla’s diet, this energy forms a highly significant proportion of the gorilla’s total energy intake.

      These SCFAs must be added to the fats already present in the gorilla’s diet, which gives us the following proportions:

      Overall energy
      (kcal) per 100g %age
      Protein 47.1 24.3%
      Available carbs 30.6 15.8%
      Fat 4.9 2.5%
      SCFA from fibre 111.0 57.7%

      This gives totals of:

      protein = 24.3%
      carbs = 15.8%
      fats = 59.8%

      In other words, although the western lowland gorilla’s diet, exclusively of leaves, looks like a very low-fat, carbohydrate-rich diet, it is actually a high-fat, moderate-protein, low-carb diet.”

      Reference

      1. Popovich DG, et al. The Western Lowland Gorilla Diet Has Implications for the Health of Humans and Other Hominoids. J Nutr 1997; 127: 2000-2005.

      Ruminants do the same.

      Let that sink in… The fibre is fermented by intestinal bacteria to produce short chain FATTY acids (i.e. FATS). The kicker is these SCFA are also almost ALL saturated!!!

      This is found at the following web site:

      http://www.second-opinions.co.uk/should-all-animals-eat-a-high-fat-low-carb-diet.html

      There are references for the article (about 8 or so I believe)

      Even those herbivores are running on fats (they just need a symbiotic relationship with some bacteria to make the fats from the otherwise nutritionally poor fibrous plants).

      Secondly you write:

      “I just can’t make an argument that the body prefers fat, mainly because the brain does not utilize fat. Most physiological processes in the body (e.g., cardiovascular, metabolic, etc.) function so as to serve the brain first.”

      This is not entirely true. The brain DOES utilise (sorry I’m Australian – I spell English, not American) fats, via the utilisation of Ketones… Sure it does not use a fatty acid, but the conversion of fats into ketones provides the brain with an energy source… and quite an effective one at that.

      However yet again you are making an ALL or NOTHING argument…WHY?! Why can’t the body prefer fats in general… again to remind you no one is saying eat NO CARBS.

      And even if you did, apart from ketone bodies, with sufficient protein in the diet (over what is needed to prevent use of muscle tissue) the utilisation of gluconeogenisis would provide enough glucose for the brain, and to your point about acetone… if you needed it constantly, with NO carbs, but consuming over 50, 100 or up to 150 in carbs a day would easily supply enough (approx 120) for your brain either alone or with some gluconeogenisis.

      I just do not get why you fall back into the assumption of NO carbs is what is being proposed? The ENTIRE premise here is that fats are a GREAT energy source for most of the body, and what carbs you do need for your brain is so low as to NOT require the consumption of carbs by eating grains of any sort.

      Also, the fact we thrived and survived as a species PRIOR to the consumption of grains, just PROVES a diet minimal in carbs is absolutely FINE, if not preferential.

      Thirdly:

      ““We found (range of medians in en%) intakes of moderate-to-high protein (25-29), moderate-to-high fat (30-39) and moderate carbohydrates (39-40).””

      Nice citation. A few things:

      1) I’m wary of these studies with HUGE ranges, especially if conducted be recent observations… unfortunately (for them) no tribe on this planet hasn’t had some external influence from our “science” and “knowledge”… Even the authors state: “The objective of the present study was to reconstruct multiple Paleolithic diets to estimate the ranges of nutrient intakes upon which humanity evolved.” Reconstruct is not observe.

      2) You left out a conclusion that was important enough to be in the abstract “We conclude that compared with Western diets, Paleolithic diets contained consistently higher protein and LCP, and lower LA. These are likely to contribute to the known beneficial effects of Paleolithic-like diets, e.g. through increased satiety/satiation. Disparities between Paleolithic, contemporary and recommended intakes might be important factors underlying the aetiology of common Western diseases. Data on Paleolithic diets and lifestyle, rather than the investigation of single nutrients, might be useful for the rational design of clinical trials”

      I love this, all people like, myself, Mark (and others like us) want is for the DOGMA of low fat is good, high fat is bad to be at least TESTED scientifically. As your initial reaction has demonstrated, the prejudice AGAINST this dietary approach is SO vehement that opponents even MISS crucial facts (like it isn’t NO CARB) and go on the attack. Again without any evidence, just feelings, they cannot get around the fact that the reason you see the brain running on glucose only, is because you have NEVER let your brain run without what is in evolutionary terms a VERY high level of blood glucose.

      I was going to ignore your human milk factoid, as it’s relevance to overall human nutrition is obvious. What human milk provides a human infant is hardly proof of anything other than what a human breast is capable of producing!!! Additionally, this nutrient analysis was almost CERTAINLY conducted on mothers that eat MOSTLY carbs due to the current nutritional DOGMA! Perhaps if they were fed a diet that was richer in fats and protein they milk would be nutritionally different?! We know that milks of ALL animals are a product of the food eaten by the animal producing them (hence the issue with drug consumption during breast feeding – almost ALL drugs get into breast milk)…

      However in the end your factoid provides an answer “1.1% protein, 4.2% fat, 7.0% lactose” SO YES the % of carbs is higher… but CALCULATE the energy provided by each nutrient then you get:

      Protein – 6.27% of the energy
      Carbs – 39.89% of the energy

      AND

      Fats – 53.85% of the energy

      Again, us pro fat anti carbers are not being as basic as saying if you eat 20 gms of carbs you need to eat at least 21 gms of fats – we are saying that the MAJORITY of your dietary energy should came from fats!!!

      And this leads to the next posts you had about nutrient profiles, but first:

      “(I also agree that a ketogenic diet my be healthy in some respects for the brain, based on some interesting research articles I read today).”

      WOW – amazing (and not unexpected from me)… care to share the citation for this article (like you have for others), so that other skeptics can read for themselves and perhaps have their own epiphany!? Once again, I have to say you are better than most, for being so open to finding out more… Perhaps all this typing on my part was worth it if you even take that nugget of “new” (it isn’t new) information to counter your indoctrination… sorry I mean education by the “academics” in nutrition and physiology.

      Anyway onwards:

      “the rest of the daily requirements just for resting metabolic function (1600 kcal, for example) would have to be made up in large proportion in fat and protein. 100 grams of carbohydrate is only 400 kcal. Healthy, daily activity would about double the required calorie intake. This paradigm (100-150 grams carbo) seems to be okay just to meet resting metabolic needs (or to lose weight), but remember that our primitive ancestors were also distance runners! There’s has to be room for calorie intake for physical activity.”

      Again a few things:

      1) True 100gms is only 400 kcals (and 150gms (Mark’s suggested upper limit) is 600 kcals). However consider how the primitive man would get even 100 gms of carbs. You have already acknowledged that primitive humans did not eat wheat, rice or corn (we couldn’t as they are toxic until processed and then cooked). They mostly ate leafy plants and fruits… I trust you still agree.

      Well lets just do the math as they say.

      You can look this up yourself, but the carb content per 100gms for almost ALL leafy plants ranges between 1g – about 5gms, with an average of 3gms (I haven’t found higher, in checking spinach, lettuce, cucumber (technically the fruit), celery, etc but there may be). Let’s be generous and say that for some reason plants have LESS carbs than they had in the past (unlikely as humans have actively SELECTED for increased sweetness in ALL domesticated plants).. and even add 50% to the TOP figure that so we say (artificially mind you) that ALL vegetable matter that humans eat has about 7.5 gms of carbs per 100gms (i.e. 7.5%). And let’s assume that when it isn’t season for fruit that you can only get carbs from vegetable matter – fair assumption I believe?

      So to get 100gms of carbs (JUST 400 kcals as you point out), you would have to eat 100/7.5% = 1333.33 gms – or 1.33 KILOGRAMS (2.93 POUNDS) of vegetables!!!

      Mind you this would be RAW until we were able to cook!

      For 150gms (600kcals) = 2kgs (4.4 lbs) I call BULLSHIT!!! There is no way our primitive ancestors were chewing 2kg/4.4lbs of raw vegetables every day… what’s worse if we take the ACTUAL average 3% carbs the figures are mind blowing, with 5kgs/11lbs for a measly 150gms of carbohydrate!!!! NO WAY, they would spend all day eating… let alone the rest squatting to excrete all the undigestible fibre.

      Now let’s say they did have fruit during the seasons. And let’s take bananas, because they are some of the HIGHEST % carbs of any fruit.

      A banana has 22.8 gms of carbs per 100 gms – or 22.8% (data from fitday.com) Now taking this as the % carbs for ancient man (which it WASN’T bananas are THE food that has consistently been artificially selected by man to add more sweetness, wild bananas are borderline sweet – but i’ll concede it for this comparison, as I cannot know what the ancient carb composition of bananas was, even if I’m near certain it was less) and then doing the same calculation:

      150 gms (600 kcals) of carbs would require 150/22.8% = 657.89 gms (1.45lbs) of banana. According to fitday.com that roughly equates to nearly 4.5 “EXTRA large (9″ or longer)” bananas!!! There is NO way we were walking around finding that many LARGE bananas each and EVERY day – let ALONE more than that.

      2) “remember that our primitive ancestors were also distance runners! There’s has to be room for calorie intake for physical activity”

      I am confident about this (as I have done my own research into this subject) and I even contributed to one of Mark’s posts last year, after which he asked me for the reference, and then wrote his own piece summarising the data. The original post Mark wrote is here:

      http://www.marksdailyapple.com/case-against-cardio/comment-page-2/#comments

      My comments (as Luke in Oz (Oz being Australia)) pointed out research by Dr. Daniel Lieberman. It also included the excellent youtube link that shows that we walk/jogged/sprinted/walked when we hunted (not an all out run):

      http://www.youtube.com/watch?v=9wI-9RJi0Qo

      On that tip about the Lieberman research Mark looked into it and wrote this post:

      http://www.marksdailyapple.com/did-humans-evolve-to-be-long-distance-runners/

      Between both those you will see we were NOT the long distance runners that some want us to believe we are. We mostly walked and tracked, with some jogging and sprinting as well.

      ALSO – not EVERYONE in the tribe hunted (although an interesting factoid is that the females also hunted at times). The hunting party was a select group (no doubt chosen for their skills), and as the victors of the hunt, no doubt go to choose the select animal parts to eat. aLso interesting is that it has been shown that hunter-gatherer tribes that have dogs to assist with the hunt or in their camps do NOT feed the dogs the organs, offal and fatty cuts, they eat these preferentially (due to nutritional value) and throw the dogs the LEAN cuts of meat.

      So these members of the tribe definitely had high energy expenditure on days of the hunt and were fed accordingly with PROTEIN and FATS.

      However it is well documented they did NOT hunt every day. After a long hunt like the one in the video they would REST for at least a day (if not more). Additionally many studies have demonstrated that hunter gatherer cultures were NOT in constant search for food and that they had significant leisure time, especially compared to us rat-race modern humans.

      Again let’s do some maths:

      25yo – 5’11” (180cm) male, weighing about 158.7lbs (72kgs) (BMI of 22.2 – which would be typical for a hunter-gatherer, I trust you agree). I picked 25, as it is a fact that hunting and tracking is NOT an easy skill, and the lead hunters were at least this age if not older (the Lieberman study shows the age was about 35).

      Basal metabolic rate = 1789 kcals

      Based on the data from Lieberman of average of about 6km/h (~4mph) for about 4 hours average (which is about right, as the typical distance was 35kms (~22 miles), then from caloriesperhour.com I calculate the energy expenditure as 2,885 kcals

      Meaning that day the expended ~ 4674 kcals – massive huh!?

      Yet, next few days they rest (one kudu or wilder beast yields ~ 120kgs (265lbs) of edible mass – so even for a tribe of 20 that provides 6kgs (13lbs) of meat per person – which is enough for DAYS without another hunt (humans learnt to dry meat for preservation) very early), basically lounge around to recover, so lets say compared to BMR, they burn ~2,200 kcals.

      Although without refrigeration they tended to FEAST up big on the meat and fat from the hunt on the night of the hunt and morning after the hunt and then just eat the gathered nuts, seeds, leafy plants and fruits in the days between. They also could fast for some time if needed.

      Anyway lets say one day hunt then 3 days off, total energy over 4 days is 2819 kcals average per day.

      With 6kgs of meat and nuts and seeds and leafy vegetables, this is not hard to fulfil. Also note that non-hunters needed far less, as they didn’t have that spike.

      Now let’s say from the average of 2800 kcals they did consume half of their carbs from vegetables, and the other half from bananas (which would be a rare luxury – but hey I’ll give it to you, EVEN at the artificially HIGH 5 carbs per 100 gms of 7.5%). To JUST meet your requirement of at LESST 150gm of carbs per days suggests:

      600kcals from the carbs in leafy stuff and fruits (1kg leafy stuff AND 2 bananas EVERY day)

      That leaves 2200 kcals

      Lets say a typical human just cannot eat more than about 200gms of protein a day without feeling stupidly full (anyone that tries to eat that much protein a day usually can’t because the ability of protein to make you feel full means they just can’t shove any more in their mouths!!)

      Assuming ~25% protein per 100gms (typical for most meats that are not LEAN), then this means they eat about 800gms of meat to get another 800kcals

      Leaving 1400 kcals for fats… fats are the ONLY way they could get the rest of their energy.

      At 9kcals per gram, they would need to consume about 156 gms of fats (~1404 kcals) to get to the daily requirement.

      THEY HAVE TO EAT fats (from the animal, nuts, seeds – wherever), because if the even ate JUST half that amount of fat to give only 700 kcals per day from fats, they then need to make up the other 700kcals from carbs or protein.

      With both being 4kcals per g – that means another 700/4 = 175 gms of carbs or protein or a combination of both. Lets split it down the middle at 87.5gms for carbs and 87.5 for protein.

      Thats another ~600gms (1.3lbs) of leafy stuff PLUS ANOTHER banana to make up the 87.5 gms for carbs and another 175 gms of meat… REALLY!?

      If you want to argue their energy expenditure was higher, then you just make it even HARDER for carbs to be the energy source!!!

      The most efficient way for ancient humans to get their energy requirements for each day was to eat FATS – PERIOD. Without grains (that give ~ 50-80% per 100 gms carbs) at their disposal, then the only way to get all that energy, without spending your WHOLE day chewing and crapping was to eat FATS.

      If you look at the available carbs in the foods they could get, the only choice was to eat more fat, otherwise they would starve. There is no way they ate kilograms of green stuff, and so many bananas (when if at all they were available)… without grains they HAD to eat fats and protein, and this is why the human body MUST run fine on fats and protein with a few carbs.

      Now for your quote from a paper:

      ““Our macronutrient projections for worldwide hunter-gatherer diets indicate that these diets would be extremely high in protein (19–35% of energy) and low in carbohydrate (22–40% of energy) by normal Western standards, whereas the fat intake would be comparable or higher (28–58% of energy) than values currently consumed in modern, industrialized societies.””

      1) This looks like observations of current hunter-gather tribes. These tribes have cooking, so they can now eat tubers and more starchy vegetables.

      Now I know we can cook, but for at least 75% of the existence of homo sapiens we did not have cooking, so our biochemical pathways are skewed towards not eating starchy vegetables.

      Additionally even when we did learn to cook, we only started FARMING about 10,000 tears ago… prior to that finding a tuber or starchy vegetable was not as easy as grabbing a bag of spuds from the grocer!!! So again, whilst they no doubt ate and very much enjoyed those bags of carbs when they found them, you could not assume they ate these regularly, let alone every day!!!

      2) By the way, taking the low end of 22% carbs (come one I have given you so many overestimates above), then 600 kcals, if 22% of daily intake = a total intake of ~2730 kcals per day… up near where the hunters above would need… and WAY lower than the 200-300 gns of carbs in the western diet (300gms of carbs with a 50% – 80% carb content per 100 gms is NOT a lot of rice, pasta, bread, corn etc, it is near IMPOSSIBLE to get to eating leafy vegetables and some fruit (unless you make that fruit a juice)

      “DATA SOURCES:

      We performed MEDLINE and bibliographic searches for English-language studies published between January 1, 1966, and February 15, 2003, with key words such as low carbohydrate, ketogenic, and diet.

      CONCLUSIONS:

      There is insufficient evidence to make recommendations for or against the use of low-carbohydrate diets, particularly among participants older than age 50 years, for use longer than 90 days, or for diets of 20 g/d or less of carbohydrates. Among the published studies, participant weight loss while using low-carbohydrate diets was principally associated with decreased caloric intake and increased diet duration but not with reduced carbohydrate content.”

      OK this one gets me slightly peeved…

      You have studies from 1996 – 2003…

      The whole fat is bad, carbs are good hypothesis (Ancel Keys is the “scientist” responsible for this whole mess) started in the 70’s… after that the US government decided to issue food pyramids based on Key’s flawed data.

      After that almost all studies were conducted from the assumption that low carb (and hence higher fat/protein) were bad. In double blinded studies this sort of bias could still influence the interpretation of the results, because whilst the measurements were blinded, the analysis and reporting is not.

      In DIET studies that by definition CANNOT be blinded (people know what they eat, and researchers know what they are eating), the possibilities for bias are HUGE.

      This is what I like to use the logic of the maths of above combined with the knowledge of what people did eat – you can’t just say – oh well, Palaeolithic man must have been eating rice – we KNOW this is not true. We know what they had available both prior to cooking and after, but prior to agriculture and eating grains. Using the KNOWN nutritional values of these foods, we can determine whether eating 2-5kgs of leaves for 600 kcals makes sense!!!

      The other issue is design… the type of fat used can skew results, particularly if in an attempt to reduce variables (i.e. bias), the participant is fed some sort of “food goo” that is made up of either fat, protein or carbs… this approach is often results in bias towards carbs, as sweet stuff is alway more palatable than protein goo and fat goo (especially COLD fat goo).

      Additionally, often the diet studies do cross overs, with LESS than the 2-4 weeks that is recognised for the human body to get off the carb addiction and firing efficiently on the fat burning mode – hence AGAIN they bias the results, as often the participants will feel fatigued and drop out – like ALL addictions, slowly removing carbs and weening off is the approach to reduce withdrawal symptoms – although cold turkey gives the best results if you can get through the initial stages!!! ;-)

      Finally (for this one) the conclusions do NOT mean low carb diets are NOT the best nutritional approach – they just mean these studies, with all the possible flaws in design they would likely have, cannot say they are good OR bad… so what?! At a minimum this conclusion means that low fat/higher carb diets are the SAME (as this would have been the comparison diet!!!)… so if there isn’t enough to say low carb isn’t good or bad, then the SAME can be said of the comparison.

      Finally, look at one of the criteria for the “particularly” exception – less than 20g/d of carbs!!!

      WHERE on this site, and WHEN has ANYONE suggested less than 20g/day (OK on a fast day you get less than 20g/day, but you also get ZERO fats and proteins!!!)… the recommendation is 50-100 for weight loss “sweet spot” and 100-150 for maintenance… this is WAY above this criteria!!!

      I do note your statement that you are more in agreement with all of this now… although I noticed all these citations and statements, which suggests you are still holding out.

      I REALLY do hope you don’t mind me bashing out these monster replies, but each point is worth addressing, and hopefully you WILL keep looking into this.

      Trust me, as I said I came from the most CONVENTIONAL WISDOM of industries (Big Pharma), and I was skeptical at first… However the science DOES support this approach, but it means going beyond nutrition science and drawing on evolution, biochemistry, anthropology, history, politics (BIG PART of the nutrition policy debacle) and economics (lets face it – if we never jumped onto cheap nasty carbs, probably AT LEAST 50% of the human population wouldn’t even exist – removing grains from your diet (particularly corn and soy products) means 80% of what is in a supermarket is now inedible!!!). Lastly you need to apply natural skepticism to “official” views and have the ability to apply some logic (as above – 5kgs of leave PER day – not likely!!!)

      When you taking a broader multidisciplinary view to the question, the answer is ALWAYS the same – the human body (and that of all animals once you include the fatty acids created the symbiotic bacteria in herbivore intestines) runs optimally on a diet predominately consisting of fats, protein and a FEW carbs.

      This is how Charles Darwin came up with evolution by natural selection. He was not stuck in one view of the world through the eyes of biology, he also recognised and understood geology and geological time (which immediately gave him more than 6000 years, he understood environments and climates and recognised ecological niches, which allowed him to recognise the similarity of “role” that certain animals had in many different countries and ecosystems (an apex predator, the small mammals, rodents, birds, ruminants, each with a similar evolutionary niche in their environment. And finally he was a keen observer and was willing to discard what he thought he knew about the world and was taught about how all the animals and plants came into being. He also had the ability to use logic to look at seemingly different data and see that one thing lead to another and it was consistent with what was observed… This is why he is the GREATEST scientist that existed… he literally changed our understanding about EVERYTHING… what is more, what he proposed was before the explosion in fossil discovery, and then DNA, both of which reinforce his insight into how things evolved on this planet… Was he 100% right – NO, but he was a damned side more correct than the official view of the world.

      So I can only encourage you to look beyond nutrition journals (all your citations are from nutrition journals) and read some journals in the other areas I mentioned above, and even more areas if it adds to the knowledge of this area. Also, don’t just read journals… read books and blogs and websites (they are NOT all intellectually lacking – granted most are)…

      Anyway, I rarely post here, and usually I have my say and then leave everyone else to have their say for a good 3-6 months (check in every 2nd day and read 1-2 articles a week though), so I will leave this MONSTER post as my last for now.

      Good luck with your exploration of this topic, I know that like your views on ketones have shifted, the more you look, the more you will realise that there is a better way for human nutrition… the fact you are so qualified and discovering this now is brilliant, as it may mean as an insider you could change it all!!!

      Over and out!!!

      Luke

      Luke wrote on June 2nd, 2011
      • Hey, I REALLY appreciate everything you wrote down here. That was an amazing summary. It really helped me connect the dots.

        George wrote on October 23rd, 2011
  19. I guess everybody sees what they look for, I see “there is insufficient evidence” as “there is not enough evidence yet”, others see it as “this is proof against it”.

    Oddly, I just posted another study, done by the Heart and Vascular Institute of the Johns Hopkins University School of Medicine and its conclusions were predominately in favor of a LCHF diet. Of course they had to throw in the meaningless phrase, “healthy fats”, but at this point, such is to be expected.

    Bill DeWitt wrote on June 1st, 2011
  20. Actually, reviewing how that study was done, the phrase should be read, “We were unable to find sufficient evidence”… the evidence is there, you just have to know how to look for it.

    Bill DeWitt wrote on June 1st, 2011
    • Not unable. I would bet money the more accurate word would be “unwilling.”

      Howard wrote on June 1st, 2011
  21. Just ran across this, thought it might be of interest here –

    “The athlete with more efficient fat conversion moves at a faster pace when fat is the main energy source. In the 1989 Hawaii Ironman Mark Allen ran a 2:40 marathon (the fastest recorded in the event) following 5:30 of hard effort. No human has enough carbs left on board to sustain such intensity for 8 hours. In a state of carbohydrate-depletion, his rate of work in the marathon depended on an ability to oxidize fat at a rate of 1.15g/minute, which is roughly 50% higher than most national-class athletes can achieve. An average level of fat oxidation (.76g/minute) would have produced a much lower rate of work and a time for the marathon of 3:30.”

    http://www.gymjones.com/knowledge.php?id=17

    Bill DeWitt wrote on June 9th, 2011
  22. OK, It held my previous post for moderation because of the link, but here’s the quote (below). I’m thinking about doing a 200 mile hike while fasting to see if it can be done. I’m pretty fully keto-adapted to moderate exercise, and have fasted for 3 and 5 day periods while walking 3-4 miles a day. If I get a break in my classes, it might make a good experiment.

    “The athlete with more efficient fat conversion moves at a faster pace when fat is the main energy source. In the 1989 Hawaii Ironman Mark Allen ran a 2:40 marathon (the fastest recorded in the event) following 5:30 of hard effort. No human has enough carbs left on board to sustain such intensity for 8 hours. In a state of carbohydrate-depletion, his rate of work in the marathon depended on an ability to oxidize fat at a rate of 1.15g/minute, which is roughly 50% higher than most national-class athletes can achieve. An average level of fat oxidation (.76g/minute) would have produced a much lower rate of work and a time for the marathon of 3:30.”

    Bill DeWitt wrote on June 9th, 2011
    • Athletes consume carbohydrate during these types of races. Mark Allen consumed carbohydrate during this race. They are not carboydrate-depleted.

      Seth wrote on June 12th, 2011
      • Well then, there you go. No need to even think about this anymore, we have our answer, since “Athletes consume carbohydrates during these types of races” and Mark Allen is an athlete in once of these types of races, presto facto, he clearly ate carbohydrates during this race, which proves that all atheletes are not carb depleted during these types of races, because they all eat carbs… A perfect circle of logic, defended from all sides, preventing the need to ever learn anything we don’t already know. Thanks Seth! And BTW, your links to that were fascinating!

        Bill DeWitt wrote on June 12th, 2011
  23. Thanks Bill Dewitt….for the post about Mark Allen in the ’89 IRON MAN run…
    Take that …Mr. “bag of cornstarch”…
    LOL GROK ON>>>

    Daveman wrote on June 9th, 2011
  24. Excuse my ignorance, but what’s an HEDer.

    Thanks

    Rizsa wrote on June 11th, 2011
  25. Why does the myth that the more you exercise (read, athletic), the more carbs you need to fuel energy?

    In exercise, as in daily activity, protein converts to glycogen in the absence of carbohydrates.

    I have cycled (mountain biked) up the Andes (now this was day in day out for over 17 days) and many similar terrains. I have run 10km+ fun runs and run around 8km at least 4-5 times per week and neither I or my performance has suffered. In fact most people are astonished that I can perform at the level that I do on “low-carb”.

    I have also lived and traveled extensively in Asia. Westerners assume Asians eat rice in the same quantities that we do when we frequent an Asian restaurant.

    They do not. The Japanese would eat a finger bowl of rice and then leave some in the bowl. The Chinese would eat a finger bowl of rice. The Indians eat the most rice. Asians do not pile their (large) bowls up, Mt Vesuvius high and then order second and third servings of rice to “mop up the sauce”. In an authentic chinese restaurant (in the US, UK), the waiting staff are often surprised when tables order more rice than served initially.

    Finally as to comments that carbohydrates are older than “civilisation itself” – this is true. Carbohydrates were probably on this earth before primates even got to the trees.

    However, man eating carbohydrates is not as old as civilisation itself (other than in PB quantities). Man only began harvesting wheat and grains 7k or 20k (Im sorry, I forget which) years ago!.

    Finally addressing the same posters comments – if we only ate the amount of carbs that our grandparents did, we’d all be fine. The copious consumption of carbs at every meal and even as meal substitutes is a very modern day phenomena (about 50 years and getting worse each subsequent decade).

    Epigenetics aside, it takes much much longer than that for evolutionary changes to occur. We will not see the evolutionary changes required for some 100,000+ years.

    Keep up the good work Mark.

    A fantastic site.

    ps I have been low-carbing/PB’g for 11 years now!

    Buzzy2010 wrote on June 12th, 2011
  26. Anecdotes are indeed poor evidence Seth, but not nearly as poor as imaginary, untested, hypothetical situations which are asserted to work out in favor of your point of view. Mark provided his working definition of the term “prefer” and someone choosing a different definition and using that as an argument is a classical fallacy, which your education should name for you.

    Bill DeWitt wrote on June 18th, 2011
  27. none of you clowns can reproduce evolution purposefully in a laboratory but it all happened by accident in some swamp somewhere…sure glad those fruit trees crawled out of the oceans and planted themselves and the bees elovled themselves to pollinate them

    brad johnson wrote on June 23rd, 2011
  28. Great Post! I missed this post on my own personal holiday. Something about May 19th that always comes up for me.

    bradley wrote on July 11th, 2011
  29. Nutrition has always interested me, but I’m one of the “outliers” in the graph, being that I have always been classified as underweight. I would love to gain weight (lean muscle, of course) but nothing has worked so far.

    Considering the common weight concerns in the nation right now, many people look at me with a mix of jealousy/envy/anger if I mention that I would like to put on a few more pounds to hide my skeleton. I feel like it is accepted as OK to be looking to lose weight, but arrogant, or even insulting, to be looking to gain weight. Let’s just say, not many people understand my situation.

    I’m 33, male, 6ft, 152 lbs. I’ve tried heavy weight lifting, protein shakes, raw eggs, etc, etc, but nothing seems to work.

    Just curious as to what the PB diet could offer to me. I’ve always planned to live till 100+( original plan was to be on Mars, but, oh well), but just now getting serious about that joke. :-)

    Any advice on healthy weight gain diets, or longevity in general? I’ve also seen studies related to fasting and longevity, and would love to hear thoughts on that.

    Thanks.
    An underweight (yes, we are out there) nutrition hobbyist.
    Brandon

    Brandon wrote on July 25th, 2011
  30. So why does fruit taste soooo amazing then? And why am I not at all fat with a high fruit diet. I do have lots of energy.

    Saying all carbs are the same is like saying all fats are the same.

    Nick wrote on August 30th, 2011
  31. Hi,

    I understand all of this, but what if my goal is to gain weight and build muscle?

    I’m in my early 20s and began the paleo diet in 2008. I just recently stopped a few weeks ago because I wasn’t seeing any muscle growth and felt weak in the gym. I now eat rice before working out and have the energy to lift heavy. Prior to the paleo diet, I was a bread addicted teen and always ate low-fat. I was 130 and 5’8 (more muscular). When I went paleo, I went down to 120 (lost muscle, no energy, but no acne!). I tried increasing fat while on paleo, but still had little energy to lift.

    Am I just better suited to eating more carbs?

    `will wrote on September 14th, 2011
    • If you lost weight beyond excess fat, you probably weren’t getting enough calories. The paleo diet has far less variety than a carb heavy diet, and just requires a change of habit. Utilize fat sources, such as olive oil, coconut products, and seeds to boost your calories intake.

      Takes a bit getting used to when we are used to eating a bit of meat with a huge serving of mash potatoes or rice. Or whipping up some beans, or cranking out a huge bowl of cereal just for the heck of it. Or downing an entire pizza.

      Remember, lean mean isn’t that calories heavy. 4oz of lean chicken only has like 110 calories. So a plate of chicken and vegetables might be anywhere between 200-300 calories. You’d have to eat 6+ meals of that to get enough calories if you were lifting. Again, I think it’s all about utilizing fat sources.

      George wrote on October 23rd, 2011
  32. I remember when I was doing “Body For Life”, and after 5 weeks I got so frustrated that it was not working, I called the 1-800 number and they told me that the people who succeed on the program i.e., the ones who win the $$ are the “genetically gifted” types that Mark posted about above. Wow! What a scam! I was working out 6 days a weel and following the diet to a “t” with no results.

    KingdomWarrioress wrote on September 20th, 2011
  33. Hi Mark,

    What happens to a dietary fat that was not used as energy? Say due to an individual’s inactivity.

    Thanks!

    Vlad wrote on September 21st, 2011
  34. I found the answer. “Excess fatty acids, glucose, and other nutrients can be stored efficiently as fat” from wiki http://en.wikipedia.org/wiki/Fatty_acid_metabolism

    Vlad wrote on September 23rd, 2011
  35. To the skinny ones, I’m skinny fat too due to fructose malabsorption (otherwise I’d probably just be fat!). Try picking low fodmap vegies and getting enough omega 3s and protein, as well as less omega 6s and more sat and mono fats. I’m just trying this now, after researching fats and then finding this site. Make sure you get heaps of vegies, there’s not much carbs in them.9 cups a day is probably ideal according to Dr Wahls.

    emily wrote on October 17th, 2011
  36. Is there a grain free bread?

    Is gluten free bread acceptable?

    Jon wrote on December 4th, 2011
  37. Don’t mind the theory, but have some issue. Especially when comparing these concepts to the diet of “primitive” man.

    A) There is no real evidence of what early man actually ate, but what we DO know points to not only meats but a diet high in sugars from fruits/vegetables, and actually rather LOW in fat since wild game, fish, and birds tend to be very lean. Saturated fats would be on the low end, most being poly/monounsaturated from nuts.

    B) If carbs impact longevity and health, please examine and explain far east culture. The Japanese are among those with the longest life spans, and leanest physiques on the planet. Their diet is RICH in rice products, and vegetable starches.

    C) The leanest and most healthy athletes are among fitness models, bodybuilders, runners, etc., all of which recommend high-carb diets. The reason they recommend them isn’t because they’ve been “brainwashed” by society – but because fat simply doesn’t deliver high-impact energy, and they see it first hand when they train. The only thing these athletes say about low-carb, is that you get thin, like for contest prep (and thin does NOT=healthy).

    I could understand this for a sedentary person, someone who doesn’t want to exercise and wants to become “thin,” where thin=healthy in their minds, but for a high performance athlete, there’s no way – those are very rare cases for a reason.

    Sorry, I’m going to go with what all 99.99% of the world’s elite athletes, and healthiest, active (present day) cultures do. Eat carbs.

    But good luck everyone!!

    Skeptic wrote on December 4th, 2011
    • well said bro! 100% true for me!

      Kalin wrote on April 10th, 2012
    • The elite athletes MUST eat lots of carbs because they have so little bodyfat and they train HARD. Fat truly IS the preferred fuel for exercise and resting levels below 50-60%VO2max. Even a slightly elevated heart rate above the resting heartrate still burns 90+% FAT and only 10% glucose. But endurance athletes train at levels much beyond the body’s ability to continue to provide free fatty acids to the muscles to be oxidized (burned). Their bodies flip from aerobic to ANaerobic and the fat:glucose used ratio decreases, i.e. they MUST eat carbs to continue performing at this level or they HIT THE WALL. THAT is why they “recommend” high-carb diets. But if you are not as active, this many carbs (read: CALORIES) will make you FAT, period. These athletes also eat 3000-5000+ calories a day. Are you going to do that too and remain a non-active adult? You’re reading too much into their “advice” and CLEARLY do not know the WHOLE story lol.

      Eric wrote on January 27th, 2013
  38. Vitamin C is a nutrient absent from meats and vitamin B12 is a nutrient absent from plants.

    If you went on an all plant diet, you would get a lot of vitamin C, but no vitamin B12 and then die.

    If you went on an all meat diet, you would get a lot of vitamin B12, but no vitamin C and then…still live.

    Vitamin C is a non-essential nutrient, the body can do fine even without it. Vitamin B12 deficiency is a terrible thing.

    Ricky wrote on December 5th, 2011
    • Not so. Inuits ate fermented animal products and suffered no effects from vitamin c deficiency. I’ve even heard that the skin of seals is rich in vitamin c, but I cannot remember why. Fermenting foods, which most meat-rich cultures does, ups the vitamin content of meats.

      Ann wrote on June 6th, 2012
  39. A dietitian once told me I was making a bad decision by not eating any desserts because NOT eating desserts is a BAD thing because once I get the chance to eat it after a long period of abstaining from it, I will end up binging on desserts.

    That’s like saying to an addict that NOT smoking or doing drugs is a BAD thing because once he or she gets the chance to do it after a long period of abstaining from it, they will end up binging on illegal and harmful substances.

    This comment of mine was made possible by Noel Dibish, RD, who is an overweight dietitian and is apparently one of the “top” dietitians at Kaiser Permanente (Union City, CA branch I believe). She also says that high-fructose corn syrup is “not that big of a deal”, and that getting fat or losing fat is a simple matter of the foolish “calories in vs. calories out” concept. Thanks but no thanks, I’d rather have my dessert-free healthy body with some grains (not 9-11 servings like the way you advocate) to match my low physical activity level than to have your body with a ring of carbohydrate loaded fat cells and intestines full of putrefying junk. If you want to spent some “quality” time at a “hotel” full of people in white coats, follow this dietitian’s advice and you will have her to thank in no time.

    Now without further ado, I have a bowl of white rice to eat and a ricks

    Peter wrote on December 5th, 2011
    • haw to haul.

      Peter wrote on December 5th, 2011
  40. A dietitian once told me I was making a bad decision by not eating any desserts because NOT eating desserts is a BAD thing because once I get the chance to eat it after a long period of abstaining from it, I will end up binging on desserts.

    That’s like saying to an addict that NOT smoking or doing drugs is a BAD thing because once he or she gets the chance to do it after a long period of abstaining from it, they will end up binging on illegal and harmful substances.

    This comment of mine was made possible by Noel Dibish, RD, who is an overweight dietitian and is apparently one of the “top” dietitians at Kaiser Permanente (Union City, CA branch I believe). She also says that high-fructose corn syrup is “not that big of a deal”, and that getting fat or losing fat is a simple matter of the foolish “calories in vs. calories out” concept. Thanks but no thanks, I’d rather have my dessert-free healthy body with some grains (not 9-11 servings like the way you advocate) to match my low physical activity level than to have your body with a ring of carbohydrate loaded fat cells and intestines full of putrefying junk. If you want to spent some “quality” time at a “hotel” full of people in white coats, follow this dietitian’s advice and you will have her to thank in no time.

    Now without further ado, I have a bowl of white rice to eat and a rickshaw to haul.

    Peter wrote on December 5th, 2011

Leave a Reply

If you'd like to add an avatar to all of your comments click here!

x

© 2014 Mark's Daily Apple