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

The Definitive Guide to the Primal Eating Plan

Food Scale

Do the Math

In my recent Context of Calories post, I explained how the different macronutrients we eat at each meal (fats, proteins, and carbohydrates) have different effects in the body. I suggested that, despite their raw calorie values, it’s far more important to get a lasting intuitive sense of how much of each macronutrient you need and when you need it (or not).

But how do you do that? How do you figure out the proper number of calories – and breakdown of fats, protein and carbs – to accomplish your fitness and health goals? To lose weight? Lose fat? Gain muscle? Maintain status quo? Run marathons?

In fact, most popular daily diets look at overall calories as the main factor in weight loss and weight gain. The age-old conservation of energy Conventional Wisdom says that “a calorie is a calorie.” From there most diet gurus generally prescribe some formulaic one-size-fits-all breakdown of fats, protein and carbs. A classically trained Registered Dietician will tell you that protein should be around 10-15% of calories, carbs should be 60% (and mostly from whole grains) and fat under 30%. This macronutrient breakdown stays the same regardless of how much weight you need to lose or what other goals you might have. Barry Sears has his 40/30/30 “Zone” diet. The USDA bases everything on a choice of between 2,000 and 2,500 calories a day. But, as I said earlier, it’s not that simple. Calories do have context.

The human body uses these macronutrients for a variety of different functions, some of which are structural and some of which are simply to provide energy – immediately or well into the future. Moreover, with regards to energy conservation or expenditure, the body acts as both an efficient fuel storage depot (and as a toxic “waist” site) as well as a potent generator of energy, depending largely on the hormonal signals it gets. It will store glycogen and/or fat and it will build muscle – or it will just as easily tear them all down and use them for fuel – based on input from you: what you eat, how much you eat, when you eat, what you’re doing before or after you eat – even what you’re thinking when you eat. Yet because your body always seeks to achieve homeostasis over time, the notion of you trying to zero in on a precise day-to-day or meal-to-meal eating plan is generally fruitless (yes, Charlotte, some fruit is allowed). The good news in all this is that falling off the wagon once or twice this week won’t have the immediate disastrous effect that you might imagine – as long as you can keep your average intake under control and understand how the various macronutrients function over time.

Which brings me to the crux of today’s discussion. Not only is it nearly impossible to accurately gauge your exact meal-to-meal calorie and macronutrient requirements, doing so will drive you crazy. In fact, to accurately figure your true structural and functional fuel needs (and hence to achieve your goals) it’s far more effective to look at a much larger span of time, like a few weeks, and aim for an “average” consumption. Then you can review that average daily intake over weeks or months and adjust accordingly. Below, I’ll give you a way to figure a “jumping off” point to start with, but remember, our genes are accustomed to the way our ancestors ate: intermittently, sporadically, sometimes in large quantities, and sometimes not at all for days. Their bodies figured out a way to maintain homeostasis and preserve lean tissue and good health through all this and so can we. Our genes want us to be lean and fit. It’s actually quite easy as long as we eat from the long list of Primal Blueprint healthy foods and try to avoid that other list of grain-laden, sugary, processed and otherwise unhealthy foods. Realistically, we also want to allow for the occasional party-splurge, a pre-planned (or accidental) intermittent fast, an over-the-top workout or even a week of laziness. Where most people get into trouble is in miscalculating their energy needs over extended periods of time – not day-to-day. They don’t see the average amount of carbs creeping upwards, or they figure they need x amount of calories, but don’t have a clue as to what kind of food those should be coming from.

I start with these four basic principles to guide my Primal Blueprint eating style:

1) 80% of your body composition will be determined by your diet. Yes, exercise is also important to health and to speed up fat-burning and muscle-building, but most of your results will come from how you eat. I’ll write more on this later, so just trust me on this one for now. Suffice to say, people who weigh a ton and exercise a ton, but eat a ton, still tend to weigh a ton. I think I’ll have that made into a t-shirt…

2) Lean Body Mass (LBM) is the key to life. I’ve said it many times on this site: lean mass (muscle and all the rest of you that is not fat) is directly correlated with longevity and excellent health. Rather than strive to “lose weight”, most people would be better off striving to lose only fat and to build or maintain muscle. Since other organs tend to function at a level that correlates to muscle mass, the more muscle you maintain throughout life, the more “organ reserve” you’ll have (i.e. the better the rest of you will work). Refer back to rule #1 and eat to build or maintain muscle.

3) Excess body fat is bad. Most human studies show that being significantly overweight increases your risk of nearly every disease (except osteoporosis – because ironically it responds to weight-bearing activities). Fat just doesn’t look that great either. See rule #1 and eat to keep body fat relatively low.

4) Excess insulin is bad. We’ve written about it here a lot. Chronic excess insulin may be even worse than excess sugar (and we know how bad that is). All animals produce insulin, but within any species, those that produce less insulin live longer than those who produce a lot. Eat to keep insulin low.

Here is how I use these principles to guide my individual macronutrient intake:


Raw Steak

Protein takes priority. If there is ample glycogen (stored glucose) and the body is getting the rest of its energy efficiently from fats, protein will always go first towards repair or building cells or enzymes. In that context, it hardly seems fair to assign it a “burn rate” of 4 calories per gram. It’s like saying the 2×4 studs that support the walls of your house can burn nicely if you run out of firewood. They will, but I prefer to burn other fuel first. At a minimum you need .5 grams of protein per pound of lean mass/per day on average to maintain your “structure”. If you are moderately active you need .7 or .8, and if you are an active athlete you need as much as 1 gram of protein per pound of lean mass. That’s at a minimum, but it’s on a daily average. So a 155 lb moderately active woman who has 25% body fat (and thus) has 116 lb of lean body mass needs 93 grams of protein on average per day (116 x .8). If she gets 60 or 80 some days and 110 on others, she’ll still be in a healthy average range. And even if she exceeds the 110, it’s no problem if she’s eating low carb because the excess protein will convert to glucose, which will reduce her effective carbohydrate needs (see below). At 4 calories per gram, that’s between 320 and 440 calories per day in protein. It’s not that much.



If you’ve forgotten everything you ever learned in biology, just remember this and “own” it: Carbohydrate drives insulin drives fat (Cahill 1965, and Taubes 2007). The idea in the PB is to limit your carbs to only those you need to provide glucose for the brain and for some reasonable amount (certainly less than an hour) of occasional anaerobic exercise. And the truth is, you don’t even need glucose to fuel the brain. Ketones from a very-low carb diet work extremely efficiently at that task. Either way, ideally, we would like most of our daily energy to come from dietary or stored fats. Typically, (if you are at an ideal body composition now) I use a rule of thumb that 100-150 grams of carbohydrate per day is plenty to keep you out of ketosis (and ketosis is NOT a bad thing) but away from storing the excess as fat if you are the least bit active. Don’t forget that your body can make up to 200 grams of glycogen from fats and protein every day, too. On the other hand, if you are looking to lose body fat, keeping carbs to under 80 grams per day will help immensely in lowering insulin and taking fat out of storage. On the other other hand, if you are insistent on training hard for long periods of time, you would add more carbs (say, 100 per day extra for every extra hour you train hard). It becomes a matter of doing the math and experimenting with the results.

Ironically, it’s tough to exceed 100 grams of carbs even if you eat tons of colorful vegetables – as long as you eat like our ancestors and consume no grains, no sugars and few starchy vegetables (potatoes, yams, beets, legumes, etc). Even if you eat a ton of vegetables AND a fair amount of fruit, you’ll be hard pressed to exceed 150 grams of carbs on average per day. Our remote ancestors couldn’t average 150 grams of carbs a day if they tried, yet they had plenty of energy and maintained their lean mass. At 4 calories per gram that’s only between 400 and 600 calories per day. Add that in to the protein above and our sample girl is barely at 1,000 calories on the high end. So where does the rest of the fuel come from?


Olive Oil

Learn to love them. They are the fuel of choice and should become the balance of your Primal Blueprint diet. Fats have little or no impact on insulin and, as a result, promote the burning of both dietary and stored (adipose) fat as fuel. Think about this: if protein and carbs stay fairly constant (and carbs stay under 150), you can use fat as the major energy variable in your diet. Feeling like you need more fuel (and you’ve already covered your bases with protein and carbs)? Reach for something with fat. Nuts, avocados, coconut, eggs, butter, olive oil, fish, chicken, lamb, beef, the list is a long one. 100 grams of fats per day would only add 900 calories to our girl’s daily average, putting her at between 1620 and 1940 calories a day. Even if she averages somewhere between 1400 and 2200 calories per day over a few weeks, as long as she pays attention to protein and carbs, her body composition will shift to lower body fat and more desirable lean mass. If she decides to do some walking, a few brief intense weight sessions and a sprint day here and there, that process would accelerate greatly. If she gets to a point where she’s content with her body fat, she can even add in a little more fat to provide energy that she previously got from her stored fat.

The main thing I’ve figured out from eating this way for years is that I don’t need nearly as many calories to maintain health, mass, and body fat as I once thought I did – or as the Conventional Wisdom says I do. I eat 600-1000 calories per day less than when I ate a carbohydrate-based diet, yet I maintain slightly lower body fat and slightly higher muscle mass on even less training. Remember: 80% of body composition is determined by diet. The best part is that I don’t ever feel hungry because I base my eating on exactly what my 10,000-year-old genes want me to eat.

For a look at my upcoming book, The Primal Blueprint, click here. I’ve included a sneak peek at the jacket artwork, a PDF of the table of contents and full chapter summaries.

Further Reading:

Definitive Guides to:

The Primal Blueprint




Insulin, Blood Sugar and Type 2 Diabetes

Stress, Cortisol and the Adrenals

Prefer listening to reading? Get an audio recording of this blog post, and subscribe to the Primal Blueprint Podcast on iTunes for instant access to all past, present and future episodes here.

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. Ohhh…and I cook my chicken and fish with butter (no trans fat)

    Toni wrote on August 27th, 2010
  2. great, great article.

    David wrote on September 1st, 2010
  3. On a 20 carbs a day my body can take 1200 calories max. On more carbs, I can eat about 800 calories. My metabolism is SCREWED UP. And now, a sedentary job.
    ugh. Be grateful for small achievements. Cellulite? Turn the lights out!

    BRubble wrote on September 7th, 2010
  4. I just want to know if two slices of health nut bread are going to screw up the meat, cheese, or vegetable, inside it, and make it an unhealthy meal.

    Andy wrote on September 16th, 2010
  5. Hi Mark,
    I am enjoying reading your articles. Have you read the book, Nutrition and Physical Degeneration by Weston A. Price, DDS? If not, he devoted 10 years to travel around the world in search of the secret to health. He found the healthiest people ate their indigenous foods (which did not include modernized foods)which may have included milk, grains, meat, fish, vegetables and fruit. Do you claim that our ancestors did not drink milk or eat grains or they are just not health? Do you mind explaining for clarity?
    Thanks so much

    laura cross wrote on September 17th, 2010
  6. Hi Mark,
    I am very interested in trying the PB diet. I started yesterday and noticed that I am hungrier than usual. Is that normal? In addition, I am 5’8″ and 140 lb female who wants to cut weight for the upcoming wrestling season. Will following PB allow me to cut weight even though im at a healthy weight for my height?

    stacy logofan wrote on September 22nd, 2010
    • Hi Stacy! I am by far a PB expert, but like you I am at the low end of my weight but want to lose some fat. I have found I have to be extra strict about carbs (I am around 30 g of carbs per day, all from vegs and dairy) and have lost about 3.5 pounds since Sept 1 (the bodyfat percentage is only down 1%, so I think some of that was bloat, but as long as it’s gone, I don’t care).

      The last few days, I have been INCREDIBLY hungry despite eating plenty of cals, fat and protein. Last night after suffering for days and days, I gave in and just ate primal food whenever I felt hungry. The scale is finally down another pound this morning after being stuck for several days. I’m not sure if you’ll experience this, but I say, PB can improve all of our health (not just our waistline) and just listen to your body’s hunger cues. If it’s urgently telling you to eat, EAT.

      e. wrote on September 22nd, 2010
    • If you eat less calories than you require you will lose weight.

      Nancy wrote on October 17th, 2010
      • The devil is in the details. It’s NOT a simple balance between calories in/calories out to maintain a healthy ratio of lean muscle to body fat. As Mark has said, calories have context. Read Good Calories Bad Calories by Gary Taubes. Or, wait for his new book in a few weeks Why We Get Fat: And What to Do about It

        monkeyadded wrote on October 17th, 2010
  7. Hi Mark,
    You say to cut out sugars (which are carbs and affect insultin – noted), but what about the sugars found in fruits and especially dried fruits. Do you have an amount of sugar grams we should aim for?
    Thanks so much!

    Liz wrote on September 23rd, 2010
    • Use to track your carbohydrates (and therefore sugar of all kinds, including that in fruit) and keep it around 100g per day to maintain fat and below 80g per day to lose fat.

      For instance, an apple has about 20g carbs, depending on size. So, that’s about 20-25% of your daily intake.

      The only exception is milk, which has an insulinogenic response that is greater than the carb content alone would suggest. The likely culprit is the whey component of milk. So, hard cheeses should be OK, but you need to be careful with milk and whey cheeses like cottage cheese, ricotta cheese, etc.

      It only takes a couple of weeks of daily tracking to get a firm grasp on what to eat and what to avoid.

      monkeyadded wrote on October 17th, 2010
  8. Wow, Toni- I wish I had enough time to exercise 2- 2.5 hours every day! Good for you!

    Liz wrote on September 23rd, 2010
  9. “that’s between 320 and 440 calories per day in protein. It’s not that much.”
    – Are you kidding it’s almost imposable for me to get that much protein even when I make protein shakes.

    Ariel wrote on October 7th, 2010
  10. I’m a vegan that is why its so hard to get my protein

    Ariel wrote on October 7th, 2010
  11. Any advice for someone who is vegan and wants to try this?

    Jenny wrote on October 14th, 2010
  12. The primal eating plan is related to the ‘natural’ eating habits of man, yet should we not, as humans, be able to listen to our own bodies and respond by eating the food that our body wants? One would think that evolution would have equipped us with the knowledge of what our body needs to function, and what foods will best fuel us throughout our lives. The real problem, therein lies when others try to tell us what to eat. That we even need to be told to eat by eating plans such as this stems from a larger problem, that our society as a whole has, through advertisement, distribution, and public policy, been telling the American population what to eat for decades. This has led to a multitude of health problems in society, and also led to a market for diets and eating plans as we no longer are able to simply listen to what our body wants and have access the food it wants. Whether or not the primal eating plan is, in my opinion, the best plan for us all to follow is not the most important issue facing the American population. The most important issues are the social influences that effect our diet and health.

    Lorna Porter wrote on October 17th, 2010
  13. In my opinion there are no perfect diets for everybody. I been employing a “part-time vegetarian” approach, which I consider optimal for me. I reasoned that our ancestors, while hunting, did not have access to the amount of proteins that you are talking about everyday. I agree with Pollan where most of our nutrients should come from plants, since this is what primal man had most access to. I also employ some French philosophies such as caloric restriction through smaller portions, eating more meals but sparingly throughout the day, omega-3’s from a natural source (not from pill supplements), low sugars, good fats, particularly dairy products, and genuinely try to enjoy the process of eating. Emphasis on organic whole foods, in my opinion, is the most important thing for Americans today.

    Giovanni wrote on October 18th, 2010
  14. I have to agree with several people in terms of the amount of protein one is supposed to consume under a primal diet. It does appear that fruits and veggies were the most available sources of energy for our ancestors. Meat was consumed only on occasion.
    It is very confusing for someone to make decisions regarding one’s diet with so much contradictory information. What is one to do? The definition of “health” varies across the board. The USDA says one thing, other countries follow drastically different diets, where should one start?
    I’m definitely interested in lowering my body fat percentage, but I also want to make sure I am following a balanced diet. I am a bit wary of a high protein diet because so much of the meat on the market is not healthy, organic, and hormone free.
    I was also a little confused at legumes being paired with starchy carbs. I always thought they were a great alternative to protein??

    Alejandra wrote on October 19th, 2010
  15. This all sounds very convincing, except that there are SO many theories about how we should eat that sound convincing… The most convincing thing I’ve read is that the healthiest, longest living people in the world eat mostly plants- mostly carbs by FAR. THE longest lived people in the world- the women of Okinawa Japan- eat about 80% carbohydrates!

    Have you read studies like these? What do you make of them?

    By the way, I got to your web site looking for information about soaking grains and nuts – Thank you for providing that info.

    April wrote on November 10th, 2010
  16. April- when we talk about CARBS we are most concerned with processed foods such as grains, engineered fruits and GMOs, etc. Carbohydrate content that occurs naturally in vegetation is optimal. Some of us have to count even those carbs, but eating Primal is about eating what occurs naturally, not what the agricultural revolution forced upon us.

    DBeee! wrote on November 11th, 2010
  17. On this diet, would you say that sprinting twice a week is too much?

    Jeff wrote on November 13th, 2010
  18. Jeff,

    I am doing P90X and Insanity. I am 5’9″ and weigh 199. I love white rice (I’m Puerto Rican and my wife is Filipino). Would I be able to still eat rice on the weekend (in very small amounts) or would that throw off my insulin levels after eating a primal diet. Also, is it ok to have a protien shake containing 1 cup of skim milk and a banana? At the moment I am constantly hungry. Is my body going through withdrawls for bread, rice etc?

    Paul wrote on November 15th, 2010
  19. In the end carb or no carbs, it all comes down to caloric intake. Eat to many calories… You will gain weight. Eat less calories… You will maintain or loose weight.

    Mark says eat 20 to 50 to loose weight…
    That’s Atkins !!

    Eat 80 – 100 you may still gain weight if you
    Aren’t watching your calories.

    To lose weight just eat less and drink a good quality whey protein drink 120 calories 25 grams of protein… Drink 2 of them a day. You WILL loose weight. No if’s and’s or but’s about it !

    Thomas Mollo wrote on December 12th, 2010
  20. Thomas, I agree with your post. A few years back I went low carb (no fruit, no grains, no starchy food like squash/potatoes) and I gained a whack load of weight..about 13lbs in 4 months. I kept up with the low carb eating but it wasn’t until I started counting calories and jogging regularly that the weight began to go down.

    Atkins even says calories count. It says when you get closer to your goal you may have to start counting. Why? Because calories is what counts with weight loss.

    Lower carbs, in my opinion, are more of a health thing. For diabetes, colitis, etc. I won’t do low carb again unless I’m counting .. and if I’m counting I’m going to count in some carbs !

    Heather wrote on December 12th, 2010
    • My initial low-carb experience was similar. The cravings for sweets went away, but I was eating too much fat & consequently too many calories. Once I adjusted down the fat and started adding more vegetables (but still limiting the carbs – no more sugar & very rarely starches & grains), the weight came off. I think the key is that the low-carb helps you to resist cravings for junky foods so that you can tolerate limiting your calories to a point where you start losing weight. I am pretty carb-sensitive, so every low-fat diet has resulted in me sneaking out to buy brownies. Whether primal would work for you probably depends on how carb-sensitive you are.

      Elizabeth wrote on March 2nd, 2011
  21. Just a few comments from an old newbie. I’m pre-diabetic and found out the hard way that my blood sugar reads normal when I am slightly hungry, which I try to stay most of the time. To do this I have 2 small meals or 1 moderate meal a day and snack as needed. Would have never believed it but once used to it, it’s easy to do. I choose to starve to keep slim, cannot understand how big fat people can stand themselves.

    I was diagnosed lactose intolerant, LOVE MILK, and discovered that the flora in yogurt restores milk tolerance. Make sure you buy yogurt with live cultures in it. The flora give off a by-product called lactase which digests milk. Antibiotics and diarhea gets rid of them but they are easily replaced.

    I grew up cutting every little scrap of fat off my meat before anyone ever heard of colesterol. Reading about you eating fat makes me sick. Must lack the enzymes to digest animal fat.

    I’m interested in your web site as a way of increas- ing my quality of life. Oldness has decreased mine.

    Newell wrote on January 24th, 2011
  22. Lactose Intolerant? Get rid of gluten and your small intestine will heal. No gluten, no dairy problem. Yes, probiotics are essential, but celiac is direcly related to lactose intolerance. Read Columbia University’s Dr. Peter Green’s book-celiac is not just one thing.

    DBeee! wrote on January 24th, 2011
    • agreed!

      Dianna wrote on February 11th, 2011
  23. Hi Mark, so how many grams of fats per pound of lean mass/per day on average do you recommend?

    Gus wrote on January 28th, 2011
    • Gus, whatever it takes. The calculations are all in the book, but figure protein first, carbs second and fill the rest in with fat. It gets intuitive very quickly. No specific grams per pound.

      Mark Sisson wrote on January 28th, 2011
      • I’ve been experiencing some fat cravings. Like… I cooked some delicious Italian sausage for lunch and ate several spoonfuls of the hot fat from the pan. EW, right??? I also drizzled some over my green beans.

        My tummy is very happy but I feel a little disgusted with myself. I guess it’s better than craving cookies, but does anyone know why I’m craving FAT?

        elizabeth wrote on February 1st, 2011
  24. Hi! First time poster here, my co-worker sent me this site because he is following your plan and has seen great results. I have been browsing your website, and I am having a hard time find recommendations for vegetarians. Is it possible to follow this plan as a vegetarian?

    Megan wrote on January 28th, 2011

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