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Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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May 19, 2011

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

By Mark Sisson
711 Comments

There’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.

But 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.

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.

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.

TAGS:  ketosis

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711 Comments on "A Metabolic Paradigm Shift, or Why Fat Is the Preferred Fuel for Human Metabolism"

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Crunchy Pickle
5 years 4 months ago

Great Post! I was just wondering about how to best use fat as fuel/carb levels etc. As usual, a very concise and informative article. 🙂

Crunchy Pickle
5 years 4 months ago

PS – just to be honest, although I have been primal for awhile, I haven’t really taken note of carbs. What is the best resource to find out how many are in basic primal foods? Or, can I just assume that limiting potatoes and fruit is a good start?

Dana
Dana
5 years 4 months ago

Fitday, fatsecret, SparkPeople all have food trackers and I think they all plug into the USDA database. If you don’t want to deal with any tracking sites you can just go straight to the database. Google “USDA nutrient database” and you’ll find it.

If you haven’t got the conversion formulas memorized you might also open a gram to ounce converter in another tab while you’re going through the database to get a better ballpark idea of what serving size you’re looking at, especially if you’re not familiar with the use of metric measures of mass.

Nutritionator
5 years 4 months ago

I’ve been using FitDay for a while and love, highly recommend giving it a try.

Primal Toad
Primal Toad
5 years 4 months ago

I use fitday to track and nutrition data to look up a few foods. Nd includes omega 3 and 6 content.

s
s
1 year 8 months ago

what is Nd?

Peter
Peter
5 years 3 months ago
Crunchy, I started using http://www.fitday.com, and love it. It’s free. I log every bite that I take throughout the day. Each time you look up and log a type of food, it adds it to your personal “recent” foods database, so eventually you won’t be searching for foods anymore. I never was a “food-logger”, and found it eye-opening to use this tool. Not only to keep track of calories, but it provides a great pie chart every day to show the percentage of calories from fat, protein and carbs. Like Mark has said, I have found that by sticking to… Read more »
Wendy
Wendy
1 year 5 months ago
Love your post, i agree that there is a bit of carbs in green veggies such as green beans, brocoli etc. I am a carb addict and have been down the road of carb cycling or trying to many times, the only time i do find a difference and i love it is when i actually eliminate all grains and wheat from my diet, the spike in energy and good mood is amazing, you would think that it would keep me away from things like bread for example, but the moment i try a piece or i am at a… Read more »
Mo
Mo
4 years 9 months ago

I use some of the free trackers available online. My favorite is SparkPeople.com. You can get a complete nutritional breakdown of whatever you want to track (sodium, fat, carbs, calories, iron, fats, etc.). Another one is MyFitnessPal.com; freedieting.com, MyFatSecret.com.
It’s interesting to track your intake for a month or so and see just what your diet may be lacking.

jpatti
3 years 22 days ago
IMO, tracking on a regular basis is minimally useful. I tracked for a year when I first went on insulin, to learn to dose to my food (the only real usefulness I found in tracking over a long time period). I found I could eat all the nonstarchy vegetables I wanted, all the fullfat dairy I wanted, a couple servings of fruit daily, and something starchy once or twice a week and come in under 100 g carb/day without messing with subtracting fiber or “net carbs” or such. IMO, having THAT info, how real eating over time translates into carb… Read more »
Pavel
Pavel
2 years 11 months ago

You can check http://www.wellness.com/ for good resource on foods, their calories etc. Also in community you can find the goals, that can also help you with it. You set your goals, complete them, share them with other members of community, I got a lot fitter after using it.

I would also recommend first to check with a BMI calculator and to check for a dietician – to see what fits and what doesnt for you. Limiting is never good, you can limit also vital resources for you body, that in long term may harm you.

Take care in your journey!

tn redneck
tn redneck
5 years 4 months ago
Excellent post. I can’t give enough credit to Mark Sisson and The Primal Blueprint. January 1 of this year I weighed 278. Yesterday, I weighed 238. That’s 40 pounds I have lost eating fresh fruits and vegetables (organic when possible) and all the meat I want. I prefer certified Humane, organic chicken, and beef, although I still consume a bit of bacon, sausage, and other pork. My cholesterol is better than text book, and my blood sugar as well. More importantly, I feel better than I have in the last decade, and there is significant more JOY in cooking. Thanks… Read more »
Martin
Martin
5 years 4 months ago

Yeah I’ve definitely noticed a lot of the ‘paleo’ bloggers back-tracking on the whole high-fat, low-carb idea. You’ve got Don Matesz repudiating the notion that Grok ate much fat, Stephan Guyenet saying carbs are healthier than fat, and even Richard Nikoley draining the fat off his meat and using a fancy “fat separator” in his latest post.

Good to see Mark coming out all guns blazing to shoot them down with this well-researched, take-no-prisoners post that leaves no one in any doubt who the Primal Daddy really is.

GROK ON!!

Alex
Alex
5 years 4 months ago

Richard posted in the comments why he drained off the fat from that dish: “I wouldn’t have if I wasn’t replacing it with coconut fat. I just didn’t want [the] lamb fat to overpower the dish. Not certain it would have, just my preference.”

Primal Toad
Primal Toad
5 years 4 months ago

Richard loves his fat dude…

Alison Golden
5 years 4 months ago

I love that carbohydrate curve diagram. Tells me exactly what I need to know. Boom!

It is so frustrating at times to live around people who carb.

Melissa
Melissa
5 years 4 months ago

Haha i agree with the people who carb comment. I work at a salon where me and my boss both talk about PB to clients who are impressed with results then they like to try and argue why thats not healthy and what about whole grains. I just say well if your happy with how you look keep goin with that,find me in 20 years and we can compare then.:)

hexrei
hexrei
4 years 7 months ago

So true. So many people I know that talk about losing their belly then eat a huge bowl of oatmeal for breakfast before going to their completely sedentary job.

jay
jay
4 years 3 months ago

I’ll live with you.. No problem here

Don
Don
5 years 4 months ago

I encourage everyone to read Thomas Kuhn’s “Structure of Scientific Revolutions” which analyzes paradigm shifts in science. The process of converting a well-funded and well-established scientific elite will take a significant amount of time, but it is not impossible. Keep up the good work!

melodious
melodious
5 years 4 months ago

The “pair of dimes shift” image made me laugh out loud. 🙂

peggy
peggy
5 years 4 months ago

me too!!!

Paul
Paul
5 years 4 months ago

Oh, I get it!

Michael
Michael
5 years 4 months ago

OK, took me a sec 🙂

I don’t want to spoil it for others. It’ll come to you.

Howard
5 years 4 months ago

“there is actually no requirement for any “essential dietary carbohydrates” in human nutrition”

Vitamin C is a carbohydrate.

Robin
Robin
5 years 4 months ago

“vitamin C, also called ascorbic acid , water-soluble, carbohydrate-like substance that is involved in certain metabolic processes of animals. Although most animals can synthesize vitamin C, it is necessary in the diet of some, including humans and other primates.”
So not a carbohydrate…

Dana
Dana
5 years 4 months ago

It uses the same receptors on our cells as glucose but it’s not a carb.

By the way, eating a high-carb diet increases your requirement for vitamin C, which is why people on all-meat diets can get away with so much less C and never develop scurvy.

Tim
Tim
5 years 4 months ago

Chemically it is a carbohydrate, but since it isn’t used as a source of metabolic energy, like starches or sugars, Mark’s general point is correct.

You can’t generalise about macronutrients without braking eggs.

Primal Toad
Primal Toad
5 years 4 months ago

I just read this bit from why we get fat. Interesting but awesome. Another reason not to eat fruit. Most of it is sugar.and vitamin c. Berries are awesome and bananas are for smoothies.

Primal Palate
Primal Palate
5 years 4 months ago

The glands of animals are high in Vitamin C.

Keisha
4 years 7 months ago

I’m impressed you suohld think of something like that

Travis N.
Travis N.
2 years 6 months ago

Mountain goat liver contains between 10 and 30 THOUSAND milligrams of Vitamin C. I am surprised that I have not seen this discussed more frequently. Goat liver is by far the most vitamin C rich food in the entire world yet people keep talking apples and oranges…

Kevin
Kevin
5 years 4 months ago

Vitamin C is ascorbic acid, which is a carbohydrate-LIKE compound. Thus, the statement still stands.

Fun fact: the word vitamin came from the words vital amines from misconceptions in early research.

Dick Hyman
Dick Hyman
1 year 9 months ago

Do you spell ‘anal retentive’ with a hyphen?

Peggy The Primal Parent
5 years 4 months ago
I love this post. It’s so full of links! I am always pushing fat at my website and well, you know, you’re kind of an authority around here. It’s a pretty juicy post for reference. Question: what is your opinion of a super strict ketogenic diet? I have been trying for years to up my carb intake (the problem is even worse in recent months since my accident) but I just can’t seem to thrive with carbs. Even a little fruit or sweet potato will make me sleepy and well, all kinds of other things. I do eat something with… Read more »
Crunchy Pickle
5 years 4 months ago

I am beginning to wonder if I have the same problem… After being primal/paleo for about nine months, I had a BIG slice of watermelon this morning. Instantly i felt shaky, irritable, needing to sit down. I also notice sweet potatoes make my joints hurt. I already subscribe to your blog so I’ll get your tips for “us weirdos” as you write them in the future. 🙂

johnnyrandom
johnnyrandom
5 years 4 months ago

I’ve definitely noticed a new sensitivity to grains or sweets since going primal. It makes sense if you’ve stopped riding the insulin roller coaster known as the “Standard American Diet”.

fritzy
fritzy
5 years 4 months ago
Pickle– Are you eating the sweet potatoes with the skins on? For some people, the skins can cause joint pain. Speaking of joint pain–mine has gone down considerably since I started PBL 9 months ago and continues to improve. I just noticed the other day, when someone pointed it out to me, that I can do deep knee bends without my joints popping at all. I’m 39 and my joints have popped when climbing steps or squatting down for as long as I can remember. I didn’t even notice they no longer do this because I’ve always taken it for… Read more »
joiints
joiints
5 years 3 months ago

My joints have cracked ever since I can remember(I’m 20). Do you know if the cause is solely based on diet? I’m of an athletic frame, and quite muscular (compared to non-athletic females). I am a vegetarian, and I do eat a fair amount of grains. I’m tall, and have just attributed the creaking to my height..

TLDR; I’d like to hear your experience with creaky joints!

Ketopia
4 years 1 month ago
I started restricting carbohydrates at 465lbs and a growing cornucopia of health problems. The weight gain I went through to reach 465 was absolutely frightening. On Mark’s chart it’s labeled “Insidious Weight Gain”, and it truly is just that. My numbers kept climbing, despite following the dietary advice of my Dr’s and nutritionist. Quite literally, carbs were killing me…and nobody knew what to tell me…Except that I must not be following the advice of my health professionals (this is how they accuse you of “cheating”). I was scheduled for roux en y gastric bypass in the hope that removing an… Read more »
Diane Smith
Diane Smith
4 years 1 month ago

Wow, that is amazing! It’s great that you have achieved all this weight loss and avoided gastric bypass surgery! You’re story is an inspiration and hope to many others in the same situation. Congratulations on your success with low carb!

mhikl
mhikl
3 years 7 months ago
Michael, I’m in the same boat and always have been. Fortunately I have stuck to an Atkins styled diet since the early seventies or I would be really over weight and tired. The one time I did Ornish, 1999 keeping my fats below 9% I gained forty pounds in four months and sent my triglycerides and cholesterol well into danger zones. I wan’t over eating and was doing over four thousand steps a day. I am happy on zero carbs a day but do try to get about 2 cups low cal coloured veg a day (celery, Chinese broccoli and… Read more »
mhikl
mhikl
3 years 7 months ago

Oops, 40,000 steps.

Ian in Philadelphia
Ian in Philadelphia
5 years 4 months ago

Gary Taubes posted his cholesterol numbers yesterday. I was just curious if you plan on posting yours as well.

ben
ben
5 years 4 months ago

oh, nice one. I’d love to see Mark’s numbers.

Hal
5 years 4 months ago

Thanks for this. I’m always trying to encourage the people I care about to think outside the box and get healthy. This might be the missing piece of the pitch. It’s interesting because I’ve been working on a blog post along similar lines, though not so detailed. There was also an article about a month ago on a cyclist who had gone paleo and no longer really needed to carb-load either on or off the trail.

John
John
5 years 4 months ago

Do you have a link to any of the studies you mentioned? I am curious to read their results.

Harry
5 years 4 months ago

There will be endless debate about how much fat paleo humans ate. The fact is that they were always going for the fat in any animal they killed. I.e., their bodies wanted fat. Having gotten of sugar and grains, I listen when my body asks for something. (Of course, my body might see an ad for a fast food triple cheeseburger with a perfect looking bun, cheese, tomato and lettuce, and tell me it wants one. I have to interpret that to mean some grass fed beef with pastured cheese melted on it and a salad.)

Harry
5 years 4 months ago

…having gotten OFF….

sharon
sharon
4 years 3 months ago

dirty

College Caveman (Musician)
5 years 4 months ago

I always get into the argument with my parents regarding “the brain needing carbs and glucose” to run effectively. I could never really articulate why that well.

I will be sure to forward this link to them.

I can personally attest to low-carb work outs. There was a two week period where I worked out fasted and my diet consisted of <50 carbs a day (mostly from broccoli or berries).

I wish I had a popular outlet to share this info with, but I'll have to take it one person by one!

Jaeden Ironwolf
Jaeden Ironwolf
5 years 4 months ago

One word response(if I am remembering correctly): gluconeogenesis

Tim
Tim
5 years 4 months ago

It always annoys me whenever my friends say “Oh, so you’re doing a low-carb diet”. No! I’m eating normally, you’re doing a high-carb diet! I don’t understand how otherwise smart people refuse to look at the clear evidence of chemistry, biology, and history. Great post.

Mark Sisson
5 years 4 months ago

Tim, see that’s what I mean by “reframing.” Nicely stated.

CavemanGreg
5 years 4 months ago

Couldn’t have said it better myself. The only time I say “low carb” is when I go ketogenic. Otherwise, it’s just “normal” carbs while everyone else is doing ridiculously high carb diet.

In
In
5 years 4 months ago
Please, stop the rhetoric already. I really don’t see an agreed upon body of facts showing that “Glucose is not the preferred fuel of muscle cells…. Fat is”. The studies contradict. There is a lot we don’t know about the physiology. If anything, for modern peoples, the things I really know suggest to me the superiority of glucose: 1. Most of the world eats and has eaten a high carb diet without “insidious weight gain”. Obesity is something new to modern western and westernizing peoples. Carbs are older than civilization. 2. Everyone reading this’ ancestors for many generations have been… Read more »
In
In
5 years 4 months ago

BTW – this is only scratching the surface. Much more could be said on this.

Lbliss
Lbliss
5 years 3 months ago
1. I agree. It’s not the carbs, or at least not the carbs alone. It’s what Kurt Harris calls the neolithic agents of disease, excess: wheat, fructose, and linoleic acid that cause most of the problems with regard to diabesity. 2. Programming your genes is nothing more than bad terminology. I have some genes which predispose me to celiac disease, but I don’t have celiac. I don’t eat gluten containing grains so those genes would not be expressed. That’s my understand of “reporgramming your genes” 3. No argument that fast genetic change is possible, but in my personal experience I… Read more »
Cathy
Cathy
5 years 4 months ago

When people ask me why I look so good and how I lost so much weight, I’ve been saying “I eat real food now, and not the refined, processed stuff.” The same people who would say ‘oh, low carb diet, not safe, kooky, etc.’ say, wow, that makes a lot of sense!

J.
J.
5 years 4 months ago

Yeah, that’s what I’ve decided I’d say because they are more receptive to it than the phrases that have been stigmatized.

If they try it, in the long run, they’ll reduce carbs automatically, because processed foods are typically high in carbs.

Registered Dietitian
Registered Dietitian
5 years 4 months ago
Where are your evidenced based articles to support all of your theories?? I thought excess calories = weight gain…not carbohydrates. Isn’t it true that fat provides 9kcal/g and carbohydrate provide 4kcal/g? Therefore, that would mean more fat= more calories..correct?? Our brains exclusively use carbohydrates for fuel…if we do not have carbs we rely on ketone bodies..which therefore our bodies go into ketoacidosis… Also, when we are in the anaerobic state…we only use carbohydrates as a source…such as a sprint or quick movements…you are saying if i have a low carb diet this will be more successful?? I do not understand.… Read more »
Dr. John
Dr. John
5 years 3 months ago
As a RD, you should know better. Re-read Stryer, or Guyton Biochem books. You are still responsible for the info….Specifically pg. 770 in Stryer…integrated fuel metabolism Calories in vs. Calories out? The neurohormonal regulation of appetite destroys that idea. Satiety control in the body is a system-based entity…not linear. Humans are not “physics-beaker-experiments” aligned with the First Law of Thermodynamics. We loose heat/energy to the environment, we use energy to make energy, energy production uses enzymes…etc The brain can use ketone bodies for fuel very nicely. It does NOT exclusively use carbs for fuel. During starvation (in between meals, sleeping… Read more »
greg grok
greg grok
4 years 9 months ago

‘registered dietician’: that tells me all i need to know.

mhikl
mhikl
3 years 7 months ago

RD, MD – both suffer corporatised brain wash to conventional thinking and their boxes are closed or their would not be able to work within their professions. If the modern medical industry had any credibility we would live in a skinny world (Western Civilisation). Case closed.

Allopathy has failed miserably and that is why so many are now choosing to think outside those closed boxes of failed logic. Think Semmelweis, Copernicus, Galileo.

Remember the silliness of Ancel Keys?

jan
jan
5 years 3 months ago

ditto

jan
jan
5 years 3 months ago

my ditto went in the wrong spot.ugh It was intended for Tim’s reframing statement.

Shema
Shema
5 years 4 months ago

The depressing part of this is it’s so hard to find ‘full fat’ foods in the supermarket or anywhere. I needed buttermilk for a recipe a while back (sorry – I know I should be avoiding dairy) but it was IMPOSSIBLE to find a full fat version. I looked everywhere.

At my workplace, our cafeteria only serves ‘low fat’ chicken salad and only ‘low fat’ salad dressings, etc.

It’s incredibly frustrating.

Dana
Dana
5 years 4 months ago
You don’t have to avoid dairy if you’re not allergic to it. Just go for fermented over regular milk, and try to get grass-fed dairy if you can. It’s a good source of saturated fat in a culture that worships lean meat. By the way, buttermilk is supposed to be low-fat, if it’s real buttermilk. It comes from fermenting milk and then churning butter from it. That process produces skim milk that has been fermented with lactic acid bacteria. You can make your own full-fat buttermilk–Cultures for Health sells the culture. (They’re online.) But as buttermilk is fermented, the lack… Read more »
Bill DeWitt
Bill DeWitt
5 years 4 months ago

I would like to find out what they are doing with all that dairy fat. Call me paranoid, but if I were a company, I wouldn’t spend lots of time and money removing fat if I didn’t have a way to sell it, so I wonder if the low fat craze is just a way to have leftover fat to sell.

T
T
5 years 4 months ago

Actually, the low fat thing was about selling dairy without fat. When they make butter and cream, the good and expensive stuff, they have a lot of skimmed milk left over. The SKIMMED MILK is what they are trying to get rid of.

Ali
Ali
4 years 5 months ago
I watched a very interesting video (wish I had the link) where an independent doctor investigated the panel of doctors who set the standards for healthy cholesterol levels. His research proved that these 10 or so doctors were either getting paid directly by pharma companies or owned pharma companies themselves and they set the precedent that fat is bad, cholesterol over 230 is bad (when actually there is no correlation between cholesterol and heart disease unless your levels are 320+). Anyways if you look into Lipitor it is one of the highest grossing pharma products of all time. That’s a… Read more »
Primal Palate
Primal Palate
5 years 4 months ago

You’re right!
My husband and I have a really hard time finding FULL FAT dairy products…everything on the shelves is now fat free…frustrating.

About 2 years ago the selection was still bigger…they now got rid of all the fat.
That goes to show that the CW movement is pushing harder than ever into the wrong direction…we don’t even get a choice anymore.

Thankfully there is a Co-op 120 miles away that carries everything full fat …we drive there once a month and stock up. Hell of a drive though.

Brandon Berg
Brandon Berg
5 years 4 months ago

Buttermilk is supposed to be skim milk. If you can find Bulgarian buttermilk, though, that’s made with whole milk. Or add cream to regular buttermilk.

I’ve never had trouble finding full-fat versions of any other dairy products.

Real Food RD
Real Food RD
5 years 4 months ago

great post, because this is about so much more than just weight loss.

Dana
Dana
5 years 4 months ago
To the extent that even slender people should be worrying about this because they’re not exactly healthy either. There are slender people getting high blood pressure, demented cholesterol levels, metabolic syndrome and type 2 diabetes. But because they’re not fat they dismiss it all as “hereditary.” Like as not their doctors are saying the same thing. Fat people are lucky. We got an early warning signal. But as long as we make good health about fat-bashing, a lot of people will continue getting sick who think they are the picture of health because they are at a normal weight.
aktres
aktres
5 years 4 months ago

Yes! I was really startled last week when my friend, who has a history of life-threatening anorexia, now recovered but still very slim, told me she’d been diagnosed as pre-diabetic! She also has several auto-immune conditions. I gave her my hard copy of PB.

I’m guessing it’s due to a lifetime of fat-phobia?

Moe
Moe
5 years 4 months ago

My blood sugar problems are hereditary. It is the *results* that are not. I could eat cookies all day long and end up insulin-dependent in a few years, or eat steak and be fine.

The people around me seem to think this is a tough choice. I think I’ll go for the needles when hell freezes over. 😀

fritzy
fritzy
5 years 4 months ago

Agreed–I work in health care and see skinny type 2 diabetics almost as frequently as those who are overweight. And most of the ones with “normal” BMIs are the ones on dialysis. Of course they are not truly thin, they are, to coin one of Marks’ phrases, “skinny-fat.”

Dana
Dana
5 years 4 months ago
When people say glucose is the preferred fuel for the human body, they are misconstruing the basic biological reality that the body burns glucose preferentially. They’re interpreting that reality as the body saying “Ooh, I would really like a Twinkie right now, Twinkies are my FAVORITE!” when actually the body is saying, “HOLY S?!T! INCOMING! GET IT OUTTA THE BLOODSTREAM NOW!!!” *sirens going off* *pancreatic panic* etc. I’ve begun telling people, “Alcohol is an even more preferred fuel than glucose. So when are you switching to a beertarian diet?” Most people understand that alcohol gets burned first, when they understand… Read more »
robertbarnes3
robertbarnes3
5 years 4 months ago

Great post! I cant understand why anyone would deny what Mark is saying here. Our anatomy/physiology tell the truth about what we need to eat. When people stop trying to eat based on their morals and beliefs and start making their body work for them this will be a much healthier and happier world!

Michael
Michael
5 years 4 months ago

Thank you for this comment. This puts the “body prefers glucose” statement that I’ve often heard in perspective.

Primal Palate
Primal Palate
5 years 4 months ago

When I told my mother that I cut out all (xept fruit) processed sugar, grains, legumes and tubers out of my diet she went into panic mode, then said :” Omg, you’ll get under-sugar and die!” Like sugar was some kind of staple.

I rofl’d.

Rachel
Rachel
5 years 4 months ago

‘The body prefers glucose’

Yeah, if our bodies prefer glucose so much then why is it that when there is surplus glucose, we change it into fat to store it.

That’s not a spare tire of sugar around your middle people – it’s fat!

KL (almostGrok'd)
KL (almostGrok'd)
5 years 4 months ago

“pancreatic panic”……… nice turn of phrase!!

Bob
Bob
5 years 4 months ago
“Pancreatic panic” and “turning that poison into a fuel” are like political sound bites and not even correct. Rice has been the staple of Asians for thousands of years. They didn’t suffer insulin resistance and the likes until the recent adoption of industrial foods. As Mark pointed out, you need a lot more carb than 150 g/day if you engage in high intensity acitivities overy long durations repeatedly. I recall he suggested 100 g for each hour of exertion. Glucose is a high grade fuel when you need a lot of power for a sprint. Fat burns much more slowly,… Read more »
Monkeykoder
Monkeykoder
4 years 6 months ago
Thank you. This may be the best post I’ve seen on the internet in many years. While I’m not a dietitian by any stretch of the word I do know bull$#!! over 50% of the time when I see it. Mark has some studies backing his statements (which appeals to me) but I haven’t seen the full studies so I don’t trust them. I do however trust my body to crave what it needs (now that’s primal…) and MY body craves MEAT and vegetables and fruit. I don’t necessarily agree with the whole low-carb no-carb fad but I eat what… Read more »
Monkeykoder
Monkeykoder
4 years 6 months ago

I will have to say though one could get much the same results by removing just the processed foods and sugar from their diet. I got rid of 30lbs in 3mo doing that (almost straight from obese to my ideal weight.)

Gabriel J Wigington
4 years 4 months ago

i agree! Im good at picking out good nutrition sources and this article kept me intrigued! Ive been studying nutrition for abot 10yrs seriously! Im a kinesiology student and fitness coach so Im always trying to gain an edge with health/body comp.

Hu Tong Kwok
Hu Tong Kwok
9 months 19 days ago

Not true,

Insulin resistance is a huge problem in East-Asian, white rice eating, countries.

Adam
Adam
5 years 4 months ago

This comment needs a Permalink. Sums up the issue perfectly.

Rod
Rod
5 years 2 months ago

+1
Hate zealots–even well intentioned ones

Jeanna
5 years 4 months ago

Great post! As always. Going Paleo has made gigantic changes in my life! Thank you for what you do!

Renee
Renee
5 years 4 months ago

Whenever people warn me that I’m doing myself in by restricting carbs because “carbs are the body’s preferred source of fuel,” I tell them, well, that all depends on how you define “preferred.” Too much blood sugar is toxic, so if you define “preferred” as “my body burns sugar first because it prefers not to die,” then yes, fine. But if you define it as “my body prefers a steady source of energy,” then fat wins hands-down.

Some people have an “aha” moment…most still don’t. Sigh.

Karin
Karin
5 years 4 months ago
Oh believe me – this is soooo true. We were in Hawaii 2 weeks ago for our wedding. Of course we had a cake. A beautiful orange chiffon with lemon curd and butter cream icing. I was nearly 90% primal before the wedding. I was humming and hawing on eating any of it because I have glutin intolerance as well. But because the baker had made a cake for nearly 25 people (we had requested a small cake for less than 10 people) we had sooo much left over and we hated to waste it. I finally broke down and… Read more »
Andi
Andi
5 years 4 months ago

I totally understand where you’re coming from with the cake kicking off your sugar addiction. I did exactly the same thing on my birthday a couple of weeks ago because my Mum made me a cake and it seemed churlish not to eat a little bit. Well a week later I was still gaining weight and the only way I found to turn off the sugar cravings was to do a 36 hour fast – worked a treat, I’m now back on the weight-loss curve and no more cravings. Good luck.

bbuddha
bbuddha
5 years 4 months ago

if you can go three days with zero effective carbs you can pretty much kick the physiological craving. The psychological cravings keep coming back, I’m beating them back with a square of dark chocolate (85%)

Steve
5 years 4 months ago

Fatabulous POST MARK!

… as always, well said… love it!!!

Steve

Neal
Neal
5 years 4 months ago

This is one of those posts that is absolutely true, but won’t accomplish anything. Those that are dead set on the carbs = life hypothesis have clung to it in the face of all the facts of dietary research over the past century. Logic won’t convince them.

Ed
Ed
5 years 4 months ago

Cheer up! This will indeed accomplish something, because not *everyone* is dead-set on *anything*.

There’s always someone balanced on the fence who will come down on the right side, if given a tug.

And there are always others who’ll move closer to the fence and look at the other side.

Milemom
Milemom
5 years 2 months ago

Well sais, I Ed… I like your thinking!

jamie
jamie
5 years 4 months ago
Thank you! This is just in time for me, Mark! Although I love my athletic friends I am just so tired of their “carb-up or your muscles will get eaten away” rhetoric. I’m just as strong as they are, and they’ve got years in the gym under their belts. (I’ve got 1 year at the end of this month.) They’ve got good genetics…and hearing them say this stuff over and over again was really wracking me. I agree with an above poster who said a predisposition to gain weight is a GIFT! I may not look as “good” as them… Read more »
Bill
Bill
5 years 4 months ago

Great post, and timely too. The fat vs. carbohydrate debate seems to have really picked up recently.

If my understanding is correct, glucose is the “preferred” fuel only because elevated blood glucose is toxic. So the body has to burn it first to get rid of it.

So it’s preferred in the sense that it’s used first, but certainly not in the sense that it is superior.

Martin
Martin
5 years 4 months ago

Yeah I’ve definitely noticed a lot of the ‘paleo’ bloggers back-tracking on the whole high-fat, low-carb idea. You’ve got Don Matesz repudiating the notion that Grok ate much fat, Stephan Guyenet saying carbs are healthier than fat, and even Richard Nikoley draining the fat off his meat and using a fancy “fat separator” in his latest post.

Good to see Mark coming out all guns blazing to shoot them down with this well-researched, take-no-prisoners post that leaves no one in any doubt who the Primal Daddy really is.

GROK ON!

Brandon Berg
Brandon Berg
5 years 4 months ago

The body doesn’t have to burn glucose to get rid of it. It can also store it as glycogen, or as fat if glycogen stores are full.

Ed
Ed
5 years 4 months ago

It would be more accurate to say that glucose-burning shuts down fat-burning while glucose is pouring in.

Luke
Luke
5 years 4 months ago

Dana, best quote of the week, “when are you going beeratarian” great point and background about sugar being poison.

wilberfan
wilberfan
5 years 4 months ago

Brilliant post. Now how do I get everyone I know (and most of the people I don’t!) to read it?!!

The Primalist
5 years 4 months ago

As Mark said in the post, once you eliminate all the crap (especially grains) the result is simply low-carb. I don’t really feel like I go out of my way to keep carbs down – when I’m eating plenty of fats and meat with some veggies, it just kind of happens.

Bodhi
5 years 4 months ago

Great post! I’m glad to see you are sticking with your carb chart and not changing it. There is getting to be some fat bashing in the paleo sphere, I’m happy to see the Primal Blueprint stay the course.

Susanne
Susanne
5 years 4 months ago

I tried the PB and loved it, until I realized that the lack of grain intake had driven my already faulty neurochemistry way way way out of whack. I enjoy being able to hyperfocus at will, but not being able to make it stop was really quite detrimental at work. Any advice for those of us who would like to be primal again, but need extra help with serotonin production?

bbuddha
bbuddha
5 years 4 months ago

can you get that in a supplement? If not, try eating more turkey.

Bill DeWitt
Bill DeWitt
5 years 4 months ago

Try “The Mood Cure”, or the similar book “The Diet Cure” both by Julia Ross. Details how to stimulate more normal neurotransmitter production by supplementation of precursor nutrients.

alex
alex
5 years 4 months ago

whats more important for muscle growth , stimulus to the muscle ,total calories or # of grams of carbs in the diet.

Jim
Jim
5 years 4 months ago
I can attest to the insidious weight gain, and while there has been much about my diet that was very good, I decided to get back on track and used this carb chart to meal plan for my wife and myself. For 3 days, I don’t really watch what I eat; for 4 days, I ensure that I eat <50 g. carb. per day; for 5 days, I work out (usually short runs). So far the results have been very good for someone who's never been a "dieter": 12 pounds down in 5 weeks, and my wife has remarked often… Read more »
IvyBlue
IvyBlue
5 years 4 months ago

As my success is so apparent I’ve been getting questions about how I did it. I loan or get folks to buy the book but I can tell it won’t be followed or it will be tweaked 50 ways before it’s tried.

They are following their “Dr’s orders” after all so you are right, this MUST change. I’ll be attending your talk next week in NYC, I hope you didn’t give it all away here.

rob
rob
5 years 4 months ago
It boggles my mind that so many Paleo types will not admit that starch is a preferable fuel for athletics compared to fat … performing on fat is sheer agony compared to using starch as fuel. In the article Mark says “unless you’re an athlete …” That’s a pretty big “unless.” Okay if you’re a soccer mom I can see how you can get by on low carb, and if you are obese then you definitely need low carb, but if you are a normal healthy guy, and you are not an athlete, imo you have to seriously reconsider how… Read more »
Tim
Tim
5 years 4 months ago

True, but it is quite hard to run out of muscle glycogen. It takes about an hour of running at a moderate pace before you hit the “low carbohydrate wall”.

So if you regularly run for more than an hour, you need to eat more carbohydrate. However, if you do HIT and resistance exercise, you don’t.

Lizzy
Lizzy
5 years 4 months ago

I don’t think this guy is fueling his running with carbohydrates every hour.

http://www.youtube.com/watch?v=826HMLoiE_o

j. Stanton
5 years 4 months ago
It has nothing to do with “preferable”. Fat oxidation can go on forever (relative to a day’s exercise), as we’ve got plenty of fat…but we can only oxidize it so quickly. Glycogen can be oxidized as fast as we can take in oxygen…but we can only store so much of it. Endurance exercise is all about optimizing both of them. The high-carb brigade only pays attention to glycogen, ignoring the facts that low-carb eating, exercise, and fasting increase the ability to oxidize fat, which determines baseline performance. As Jonas Colting says, “Train low, race high.” Leangains is low-carb on rest… Read more »
mhikl
mhikl
3 years 7 months ago
So what proportion of the general public are athletes, assuming that athletes need high carbs. Maybe they are just out of sync athletes. Besides, look at the early death rates of long distant marathon runners and other intensive athletes. I have always beed a pudgy fellow with poor tone. Going raw primal I found that I lost my weight and now my body is muscular and taut and I don’t exercise any more than I did when I was overweight and flabby. Most of my fit thin friends are the same. Mayn’t be a scientific study but my health on… Read more »
Roane
Roane
5 years 4 months ago

Reposted the link to my facebook page, asking people to read! This is a great article. I went primal on 1/1/2010. Immediately dropped from 185 to 165 lbs. Never felt better, ever! Age 40. Thanks Mark! I am spreading the word to everyone, all the time. Thanks again!

Kalin
Kalin
4 years 5 months ago

What you dropped?! Fat only or muscle and fat?!

Rachel
Rachel
5 years 4 months ago
I have to say that after doing PB for about 3-4 months, I felt like hell. I was tired all the time, gained weight, and was just generally sucking at life. But I wonder if it has something to do with this: There is a downside, however: you can’t train long and hard day-in and day-out in the fat paradigm. Does the carb curve change for those who do things like CrossFit? Where is the boundary for actually needing to increase your carbs? I increased mine from about 75 a day to closer to 120 a day on average and… Read more »
Ann
Ann
4 years 3 months ago
Athletes can absolutely perform well on very few carbs. Most people don’t realize that a low-carb diet automatically flushes salts from the body via the kidney. Add to that the heavy sweating experienced with hard sustained workouts and you have a recipe for dehydration and electrolyte imbalance. I know a lot of athletes who are concerned about looking good all the time and cut all the salt they possibly can from their diets because they are afraid to retain water weight and look “puffy”, but low-carb is inherently low-salt, and salt needs to be supplemented on low-carb, especially for active… Read more »
Nadya
Nadya
2 years 5 months ago

My comment is on exact same phrase:
“There is a downside, however: you can’t train long and hard day-in and day-out in the fat paradigm.”

Doesn’t this guy train long and hard?
http://www.meandmydiabetes.com/2012/08/11/western-states-100-low-carber-wins-ultramarathon-steve-phinney-and-jeff-volek-study/
http://www.timothyallenolson.com/

Roane
Roane
5 years 4 months ago

Rachel – What was your diet like?

Rachel
Rachel
5 years 4 months ago

I quit logging my food during that time since it isn’t considered necessary, but I did log here and there, just to check my ratios. Here is what I had one day: 1951 calories, 150g fat (68%), 71g carbs (14%), and 86g protein (17%).

DAVE PARSONS
DAVE PARSONS
5 years 4 months ago

I just did a 1.5 day fast and posted a pic of what I ate when it was time to eat again..on Marks FaceBook page…
go see
GROK ON>>>

Rodney
Rodney
5 years 4 months ago
I am a work in progress as I slowly adapt the Primal lifestyle. “All in” didn’t work for me so I am trying a more gradual approach. I am currently on day 66 of a planned 100 day no added sugar eating plan. I still trend toward the higher end of acceptable carb intake, mostly sweet potato and fruit, but I don’t crave the sugary crap I used to eat. I am finding it hard to replace carbs with fat, and instead feel like my protein intake is trending up a bit too much. This is mostly in the form… Read more »
Primal Palate
Primal Palate
5 years 4 months ago

Easiest way to get fat without protein is to buy just the fat.
I have grassfed/finished kidney fat in my freezer.
Just break a piece off and fry it in a pan, add salt and enjoy.

Melie
Melie
5 years 4 months ago

I remember watching nutrition films in grade school (early 80’s) that told us that fat was good. I even remember making a point of eating the fat on steaks and pork chops because that’s what they told us to do in school. Does anyone else have similar memories? I wonder what happened to that line of thinking. You would think the beef and pork lobbyists would be all over that.

Primal Palate
Primal Palate
5 years 4 months ago

Been following the PB for a little over a year now and it works.

Even with my 1 Quart of raw milk a day!
Very impressive 🙂

Michelle Q
Michelle Q
5 years 4 months ago
Mark, I really love the Primal lifestyle–though with respect to diet in particular, I tend to feel better on the Jaminets’ Perfect Health Diet. My question concerns furious carb cravings when thinking hard. I’m a techno-geek by profession (something that while stressful at times, I truly enjoy), and when the grey matter is working madly away, I am invariably in the throes of carb cravings that I can honestly say I would otherwise NEVER get. (I am one of the lucky few who have a near-negligible sweet tooth.) What gives, besides the brain’s presumably higher consumption of glucose? And more… Read more »
Meg
Meg
5 years 4 months ago
Hi Michelle, I have similar experiences to you. My profession also requires bursts of intense thinking, focusing, calculating by hand/mind and extended periods of FULL concentration and when I’m having one of those days/weeks I also find that I crave carbs. Not specifically sugary junk things, but I end up going for things like rice and potatoes way more than I normally would. Actually this week has been mentally very, very intense and my carb intake has gone up quite a bit with minimal impact on weight or intestines like I normally would have. Maybe my used it all up… Read more »
Mallory
5 years 4 months ago

I agree…

I just wanna know where leptin plays into all this…

Andrew
Andrew
5 years 4 months ago

Mark,

I thoroughly enjoyed this post as it contradicts nearly everything my nutrition professor lectured about in college last semester. I do have one question though that is foggy to me. Generally, health advice often states that when the body does receive enough carbohydrates for energy, it turns to the protein in muscles first, as opposed to fat. Why is this used as an answer, and is there any evidence to support this statement?

Thanks!

Real Food RD
Real Food RD
5 years 4 months ago

It may contradict what your prof was emphasizing, but if the course taught any science, you should still have gotten this same info. That was always my experience, that it was there all along, just ignored.

Fat is what your body will burn after running out of glucose, such as in longer moderate exercise.

Mark Sisson
5 years 4 months ago

Andrew, your prof is mostly right. If you live in the Carb Paradigm ,where all your energy systems crave glucose and can’t access or easily burn fat, then, yes, that’s exactly what happens: you run out of glucose and the body turns to protein (usually in muscle) to make more glucose. It’s why fasting is not as effective for sugar-burners.

In the Fat Paradigm, once you have become fat adapted (up-regulated enzyme system to increase beta oxidation of fats and down-regulated glucose oxidation mechanisms), your body will look to fat stores for energy instead of muscle. No problem.

Tim
Tim
5 years 4 months ago

The main reason is that fatty acids can’t cross the blood-brain barrier, so the body needs to either make glucose from protein to feed the brain, or start making ketone bodies.

Using ketones is rather inefficient, which is why this pathway only happens after a few days of starvation (or during hypoglycemic shock when a diabetic injects too much insulin).

Ed
Ed
5 years 4 months ago

“…only happens after a few days of starvation (or during hypoglycemic shock when a diabetic injects too much insulin)…”

…or when I eat my normal diet.

Also, please Google “Fatty Acid Transport Through the Blood?Brain Barrier”. Some of the shorter-chain fatty acids are transported and metabolized.

Andrew
Andrew
5 years 4 months ago

Ahh, I see the difference. Much appreciated!

Diana
5 years 4 months ago

Great article! Thanks! Also, just wanted to say thanks for writing the book – I just finished it and it was great! I learned so much! Thanks!!!

Karen P.
5 years 4 months ago
Mark, you’re on FIRE! Love it! I know youse a busy man, but I have a question I’m not seeing an answer to yet, and maybe some kindly comment readers will know as well. So those “lucky” ones who don’t get overweight eating the SAD, are they also susceptible to the other health ramifications or are they somehow immune to those to? Is it the body’s response to the SAD that begins the cascade of other health problems and if you don’t have that response, then you’re in the clear? Just curious since many of my friends are these “lucky”… Read more »
Renee
Renee
5 years 4 months ago

Yes, skinny people can still develop all the “diseases of civilization,” including heart disease and diabetes. So being naturally skinny doesn’t automatically mean they’re healthy.

Karen P.
5 years 4 months ago

It’s so frustrating when skinny folk think they’re immune. As though all this diet is about is weight loss…ugh.

Venne
Venne
5 years 4 months ago

I think I love you.

… But on a more serious note, this was incredibly informative and further solidifies my choosing this lifestyle.
Thanks so much for everything that you do, Mark!

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Clarissa
Clarissa
5 years 4 months ago

Thanks for this timely posting, Mark. Yeah, the debate over on Don’s blog (since removed — evidently a little back-peddling on Don’s side) did confuse me about whether I should be cutting down on the animal fat and upping the carbohydrates. I’m glad to get your position on this. I’ll stick with my Primal BP shopping guide until I hear otherwise from you!

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[…] on FIRE! If you haven’t already, be sure to check out Mark Sisson’s fat salvo (click here) over at […]

John
John
5 years 4 months ago
Foraging wild foods is one of my hobbies and with the exception of the fall when the various nuts are available and a few wild tubers there are not many carbs out there for the picking. Depending on the season and where you forage there may be close to none. Occasionally I try and do a weekend where I only eat wild foods that I have collected one way or another. I always find myself falling back to the fish and game for a majority of my nutrition. I imagine that Grok was in the same position much of the… Read more »
kash money
kash money
5 years 4 months ago

Pro-carb bloggers however always refer to people in the far east who eat 500 grams of carbs a day (or something to that effect according to them). How do you explain that?

Renee
Renee
5 years 4 months ago

They do eat rice, but they still eat fewer carbs than we do. And virtually no sugar or refined flour. I wish I could remember the source, but I read that the average Japanese man consumes 1800 calories per day, roughly 50-60% of that as carbs, which comes out to about 270g carbs per day. The average American, in comparison, eats 350-400g of carbs per day. Plus ten times the amount of soda!

Karen P.
5 years 4 months ago

I think the China Study, when you look at the data and not the conclusions, shows that white rice comes out almost neutral, whereas gluten is absolutely shown to follow morbidity.

Jerry
Jerry
5 years 4 months ago

As of March 2010, China passed up India as the diabetes capital of the world. Sounds like a good explanation to me.

philco
philco
5 years 4 months ago

why does everybody thinks the whole China only eats rice? it’s not like they are high carb rice-based vegans.
have you seen all the pork they eat?

not to mention all the processed crap that, yeah, incredible, it reached their country!

yes, rice (carbs) plays a main role in their diet but mix that with pork (fat) on an absolute daily basis, of course you’ll end up with all sorts of medical conditions.

fyi

http://china.usc.edu/(S(y0wzn5awaihqgk55herhwx45)A(rNmxQAIiywEkAAAAOTY4MWIyM2YtNTM5Ni00YTA1LTk4ZGQtOTNjOGIzNWU0ZjBl1-b31o9-4IjttR0j3pb-wpdwr3w1))/ShowArticle.aspx?articleID=593&AspxAutoDetectCookieSupport=1

http://en.wikipedia.org/wiki/Pork#Consumption_patterns

Rhys
Rhys
5 years 4 months ago

Great post. I just wish all the S.A.D folks and other slaves to the status quo would read this article and embrace it. I’m in my third year of college as a Fitness and Nutrition major and I am sooooooo sick of hearing the same old bull about glucose and carbs and the food pyramid. It’s just so frustrating and it gets in the way of my willingness to learn.

Sharon
Sharon
5 years 4 months ago

Hang in there Rhys, the world needs you.

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