Mark Sisson: Why Nutrition Is The Key To Health

This week, Mark Sisson -- former professional athlete, founder of Mark's Daily Apple, and developer of the Primal Blueprint health & fitness lifestyle -- returns to discuss nutrition. In his opinion, it's the single most important factor for a healthy life.

While other key components like physical exertion, good sleep, de-stressing and sun exposure contribute to overall health and well-being, too (see our 2013 interview with Mark for a full background on his recommended regime), the food we eat can literally determine which of the genes in our genetic code get activated and expressed. So, in a very real way, we indeed are what we eat.

Which raises concerns when looking at the traditional "food pyramid" we've been told to follow since the 1950s. In Mark's eyes, it's based on poor or absent science, and recommends a dangerously flawed regime responsible for many of the chronic health problems of modern society (obesity, diabetes, intestinal disorders, etc). It's so out-of-whack that one of the single most impactful steps we can take as a society would be to flip that pyramid "upside-down":

Humans are by nature very resilient in many regards. The good news is we can live on just about anything—bear claws, seaweed, shoe leather. We have been shown over history to be able to get through long periods of famine because of our ability to extract calories from whatever we put in our stomachs. That's the good news. The bad news is that a lot of the stuff we put in our stomachs has an effect on our genetic expression. Our bodies are trying to rebuild, recreate, renew, regenerate us every day. And based on the inputs that the genes get, we either turn on genes that store fat, that make us sick, that cause or predispose us to cancer, or we turn those genes off. Then we can turn on genes that build muscle, to give us more energy, that make us more clear thinking.

And a lot of these genes operate in a principle we call epigenetics, through food signaling. So it is the types of foods that we choose to eat that cause genes to turn on or off. And we can literally discover what I call these hidden genetic switches and make our food choices in such a manner that we can have a much better chance at arriving at the desired outcome. That might be losing weight; it might be getting off the meds; it might be reducing the ADHD in a young child. All of these things are possible, and quite likely based on food choices. It does not mean that if you are somebody who is living on fast food and soda all day that you are a bad person or even that you are doomed to die at 50. It just means that you have a greater likelihood of not thriving throughout your lifetime.

The gut biome story is going to be a big story for the next two years, and has been for the last year. It is the new frontier. We have a 100,000,000,000,000 organisms living in us that are not us. You know, we have a hundred trillion cells that are bacteria versus ten to fifteen trillion cells that are human. So 90% of the cells in your body are Not You, and there's a lot that they are doing. Some of them are helping you digest food. Some are creating vitamins. Some of them are feeding the cells lining your guts. And some of them are bad. And this balance in the gut biome between the good bacteria and the bad bacteria is huge, and it is an issue for a lot of people. And it relates back to the foods you eat in several ways. One of which is if the foods you eat are causing a leaky gut and the bad bacteria in your gut are leaking into your bloodstream, that's not a good thing. A gut is supposed to be a barrier to entry and only allow the vitamins, minerals, amino acids, simple fatty acids and sugars. But the fact that it's leaking and allowing in bacteria and setting up an immune response is huge. And that is the cause of a lot of people’s inflammation and the cause of a lot of people’s autoimmune diseases. And that relates back to the gut biome. So that is point number one.

Point number two is you have to feed that biome. So the food that you eat is also supporting the bacteria in your gut. And sugar we know tends to support the unhealthy bacteria. Some of the pre-biotic fibers, resistant starches, insulin -- things like that -- actually support the healthy bacteria and allow them to produce the short-chain fatty acids that then go on to feed the cells. It is so critical: it does come down to what you eat. So much of your life and so much of your health and so much of your ability to be energetic and healthy for the rest of your life comes down to what you put in your mouth. That part of it is not rocket science. The real rocket science is figuring out within that spectrum what is best for you, individually.

Mark's organization is releasing the Primal Blueprint Expert Certification program on August 20th. Those interested in better understanding the science of nutrition, and how best to implement it in your diet, can learn more about it here.

Click the play button below to listen to Chris' interview with Mark Sisson (33m:55s):

This is a companion discussion topic for the original entry at

I was wondering where to post this piece from Physorg. About the influence of gut biomes on our decisions.
This phenomenon is more evidence that Tom Campbell is correct. We are able to influence the outcomes of the future (Within the error bars) by our intent.

Be very careful of your intent. (Be careful what you wish for.)

I'm curious if anyone can speak to the environmental impact of this diet.  I have read many times that meat production is a greater contributor to greenhouse gas emissions than even car traffic (correct me if I'm wrong please).  If the whole world switched over to this diet wouldn't it have a negative impact on an already stressed eco-system?  How can this be managed by individuals choosing this diet to reduce the impact.  E.g. rabbit is better than beef or substituting legumes for meat?  How can Paleo be made resilient for a future which might include food shortages?  How can someone who wants to produce a portion their own food adapt their efforts to this diet?  I'm interested in this, but if I'm going to try it it has to fit with the rest of my efforts centered on making myself and my family more resilient.

Check your CRP (includes correlation with cancer), Homocysteine (heart), and HbA1c (glycation, sugar control)

As Mark has said, (probably elsewhere), you need about 1 gram of protein per kilogram of lean body mass. for most of us that works out to about three ounces per day, and most of that can come for the vegetables that you eat (yes, Kale and Broccoli have protein!). The current problem is that we actually eat too much protein, and many more processed carbs than we need.Getting the correct amount of good protein should not be an environmental problem. The current problem is how we abuse the environment to extract everything as cheaply as possibly in current dollars. Fresh vegetables and grass fed beef is better for you, and even if it costs a bit more now, eating right will probably reduce your medical bills in the future.

@Thetallestmanonearth - There need not be any negative environmental impact from a Paleo diet, and in fact, I'd argue it encourages a positive impact. Paleo encourages consumption of grass-fed, pasture raised meats, organic veggies, nuts, berries, roots, tubers, fruits - all of these can be produced by means that are net-restorative to the earth. Look into Permaculture to learn more about this. Essentially, the rotational grazing of animals builds topsoil and a better microbiome, adds fertility to the soil, prevents desertification, reduces water runoff, and more. Similarly, a perennial food production system that produces fruit and nuts from trees planted alongside nitrogen-fixers in a food forest or silvopasture system, once mature, can produce as much or more calories per acre as a monocropped grain field, but without wasting all the water, without depleting topsoil, while adding fertility to the soil rather than depleting it, while being a home to a countless variety of life forms that otherwise would have been razed from the earth.Conversely, "non-paleo" foods are grains and legumes, both of which are grown in monocropped systems that rely on extensive use of pasticides, herbicides, non-renewable water irrigation, fossil fuels, cause massive topsoil loss, destroy the microbiome and displace/destroy countless species. It is hard to imagine being able to produce these foods on anywhere near this scale without these horrible costs. The paleo foods, though, can and are being produced sustainably. It is just a matter of educating people and scaling up.

With respect to the idea that eating meat is more or less harmful for the environment, the answer is 'it depends.'
Here in New England, some land is really only suitable for running animals on.  It is tilted, rocky pasture land.

The animals actually improve the soil conditions if they are run on it properly (rotated on a good schedule), so I feel that's a perfectly acceptable use.

Most of what people refer to with the heavy impact of animal farming is when we use arable land to grow grains which we then feed to animals to produce protein and fatten them up for market.  Then the impacts to produce a pound of meat are pretty high.

Another fair use, in my opinion, is for things like hogs that are excellent at converting farm and kitchen waste into protein.  

So I am not personally against meat use and we strongly favor grass or scrap fed, local meats that also support local farmers.

But for the whole world?  There I rather doubt that the math pencils out.  I doubt there's enough range/pasture land to support the quantities of meat required, but I have not run the numbers, nor seen them run.

As Mark has said, (probably elsewhere), you need about 1 gram of protein per kilogram of lean body mass. for most of us that works out to about three ounces per day, and most of that can come for the vegetables that you eat (yes, Kale and Broccoli have protein!). The current problem is that we actually eat too much protein, and many more processed carbs than we need.
@dude59 - In this article of Mark's here he says the RDA of 0.8g per kg of body weight is an absolute minimum and may be ok if you are perfectly healthy and sedentary. He then discusses several other cases (including dieters and anyone who is active) where more protein is better, up to 2g per pound (over 4g per kg). So if we take a 200lb active person trying to lose weight, it's not unreasonable he/she would want to eat 1g per pound of body weight. That's 200 grams in a day. It would be misleading to say "that is only 7 ounces of protein" because that would be a dry weight of protein that doesn't exist in food sources. Take one of the most protein concentrated foods, canned tuna -- you'd have to eat 5 cups of it (nearly 28 ounces) to get 200 grams of protein. To say that this protein can be mostly obtained from vegetables is also misleading. Cooked spinach has one of the highest concentrations of protein of vegetables (according to and has 4 grams protein per 100 grams of spinach. So to get your 200 grams of protein here, you'd have to consume at least 5,000 grams of spinach per day. That's 11 lbs of cooked spinach. Daily. Not feasible. Even if you wanted to cut everything in half and only consume 0.5g protein per lb of body weight, or just get half your protein from vegetable sources, that's still more than 5 lbs of cooked spinach. Still a no-go. To get it from a raw source -- Kale has 3g protein per 100g. So it's even less feasible than cooked spinach. I disagree with the statement that we currently consume too much protein. Study after study shows people doing better when increasing their protein consumption from real foods, especially those who previously followed the standard American diet. Mark's article, linked above, touches on this point. I know it is commonly repeated in vegetarian and vegan circles that it's easy to get all the protein you need from vegetables, but it's simply not true. The data is right there for anyone to do the math. Maybe if you consider grains and legumes as part of "vegetables," but certainly not from Paleo veggies such as leafy greens.

Thank you Kevin, dude and Chris.  After writing my initial comment I thought about my little homestead as it is now and as I have planned it for the future and realized that in a lot of ways I am already growing what could be close to a Paleo diet (as I understand it).  Most of the grain I plan to grow is for animal feed.  I do plan to grow beans and peas as storage crops, but I'm not sure how those fit in with Paleo.  We are planting as many perennials as we can (nuts, fruit and berries).  We raise chickens and we're planning for a rotational grazing system for goats, rabbits and pigs. I can see how on a local scale, in a temperate biome it is possible to sustainably eat a paleo diet.
As to my larger question: can we feed the world this way? Chris said:

But for the whole world?  There I rather doubt that the math pencils out.  I doubt there's enough range/pasture land to support the quantities of meat required, but I have not run the numbers, nor seen them run.
I agree with this, and upon further reflection I don't know that there is a sustainable method by which we can support the current population.  I guess that is one of the "predicaments" discussed here.  We have been able to grow beyond our ecosystems ability to support us only because of petroleum and agriculture inputs made possible by petroleum. Like it or not, that will end. That presents not only an personal challenge (how do I feed myself, my family and my community), but a larger ethical challenge (how do we decide who gets what when there is not enough to go around?).

Regarding the question: Can the environment support everyone eating Paleo?
I don't know. But can the environment support everyone NOT eating Paleo?

Given the amount of topsoil we lose every year, the rate at which fossil aquifers are depleting in order to irrigate grains and soy fields, the impact of climate change on our agriculture systems, I don't see how we can afford NOT to transition to a sustainable, perennial agro-forrestry/silvopasture based system ASAP. And what do these food production systems produce efficiently? Pastured meats. Nuts. Fruit. Vegetables. Tubers. All the Paleo-allowed foods. What do they not produce well? Grains. The single most non-paleo food item.

Well said Kevin.  I agree that permaculture and related techniques are the closest thing we have to a solution for our food problems.

Good interview, I read the Primal blueprint a few years ago and have gradually incorporated both his ideas on diet and exercise.  At 52 I am more fit and healthier than I've been since my early 20's. Great information.
One aspect that wasn't touched on in the interview with Mark, was the great information on his website about intermittent fasting. It isn't nearly as daunting as it might sound and can be a powerful tool.

I'm glad that the issue of economics has been discussed in this thread, though there is probably no getting around the fact that grains provide more calories per acre than anything else. So I do agree with Chris that the math probably doesn't add up for the wider world, which has no choice but to continue to rely on cereal grains as its main staple…at least until population can be brought down (hopefully, peacefully). I'd add that if the rest of the world is eating mainly grains because that is all they can afford, what does that do to us psychologically to eat a more privileged diet? What does it do in terms of empathy and communication? We already consume 1/4 of the world's resources while only constituting 1/20 of the population. We already live in an age of widening inequality. Just sayin'. 
The issue to me is not simply one of health–unless of course we are talking about a personal health issue likely caused by grain consumption, and in the case of diabetes, I'd note that unrefined grains are much less at fault than refined grains or sugar/HFCS. But looking at health from a macro-scale, it seems to me that the country with the longest life expectancy with appreciable population (i.e., not a city-state) is Japan, and we know how rice-centered the cuisine is over there. Or perhaps it's the fact that the Japanese (at least until recently) eat much less meat than we do? (It surely couldn't be their cigarette smoking!). These facts would seem to be at odds with the Paleo diet, as I understand it.

As for inverting the Food Pyramid, which was proposed a couple times during the interview, I like the idea of consuming more calories from fruits and vegetables–which are nutritionally dense–than from grains, though this will depend on local conditions–the availability and price of produce. I don't like the idea of centering the new pyramid around meat, or even fish–which is more healthful than meat, but environmentally problematic. I like the idea of grass-fed beef, but think that meat shouldn't make up more than 10-20% of daily calories, again, depending on locale, as Chris points out. Certainly I would not favor inverting the FP to elevate sweets and snacks to main foods, as has actually occurred in developed and some developing countries. The obesity epidemic is probably due as much from sugar/HFCS as from refined cereals, but the real problem is over-consumption, and that brings us to the question of protein requirements.  


Kevin writes:

So if we take a 200lb active person trying to lose weight, it's not unreasonable he/she would want to eat 1g per pound of body weight. 

It so happens that I'm a 200 lb. active person (age 62, 6') who has been tracking his protein consumption for the past two months with the aid of Nutritiondata. I've been averaging about 100 g/Day of protein, largely (80-90%) from non-animal sources. I doubt that I'd benefit from eating 200 grams. My RDA is actually 72g. (0.8 g X 90 kgs.), and I'm taking in about 1.1 grams of protein per kg. of weight (or about 1/2 gram per lb. of weight). So I'm already eating 1/3 more protein than recommended (or required). Why increase that to 200/72 = nearly triple the RDA? That seems excessive unless one is a body-builder, or maybe a football player. I'll bet that Japanese men (avg. life expectancy = 82 years) don't eat much above the RDA. I wouldn't be surprised if many of them are under the RDA. Still, I'll grant that protein needs depend on both the amount and type of activity. In my case about 2 hrs. of easy to moderate cycling and not much else. My health is generally good (rarely ill, just chronic hypertension). I certainly don't feel lacking in energy, but I've cleaned up my act in terms of eliminating processed foods/snacks, alcohol, and other forms of empty calories. That made the biggest difference to me.  

I've long been mainly vegetarian, and was even vegan for a couple years 40 years ago (probably had a protein deficiency back then). I take (some) issue with your statement that vegetarians can't get adequate protein. I agree it takes some planning (like incorporating lots of Tofu and other soy products or loading up on peas and beans). But even without the aid of soy, one can get a fair amt. of protein. Here's what I ate one day recently (protein figures courtesy of Nutritiondata). 
Oatmeal (100 g.)                     12 g. protein
Sesame seed (3 tbsp)             12 g.
Basil seed (40 g.)                     6 g.
Spinach, cooked (600 g.)         15 g.
Brown rice (1 cup)                     6 g.
Eggs (2)                                  12 g.
Watermelon seed (30 g.)            8 g.
Guava (0.8 Kg.)                         24 g. (!)
Mushroom (0.8 Kg.)                   16 g.
Total Protein                            111 grams
% protein from animal sources = 12/ 111, or about 11%
Notice I rely a lot on seeds (and nuts) of various kinds, as well as the spinach, plus some freak fruits like guava, which is extremely high in both protein and dietary fiber for a fruit. Mushrooms are also very high in protein. So one needn't resort to eating beans to get 100 grams/day of protein. This day I consumed about 2,200 calories. 
Now you may very well say that 100 grams (or 0.5 grams per lb. of body weight in my case) isn't enough protein, and I'd answer that it depends on age and activity. It seems to be enough for me. A better question might be: am I getting enough of the important amino acids?

The whole discussion felt quite authentic.  Chris wasn't simply talking about "staying fit" and healthy in some theoretical sense, but actually had real issues to discuss in his own particular case and how altering diet had positively affected him.  It comes from actually living the stuff he talks about.
It made me think: exactly what is the effect of that 8-oz coke I drink every day?

I also liked Mark talking about defending his right to eat bread.  I can identify with that!


And what to do about them.

Sometimes a bit simplistic, but nevertheless a persuasive account of the benefits of plant-based foods vs. animal foods. The data seems to me overwhelming, and that is part of the reason I went vegan back in 1970, and mostly vegetarian afterwards (with a few 'social' relapses in later life). It is hard to be vegan in a mainly meat-eating world, but the benefits are undeniably there.
Poultry comes out surprisingly as the chief villain here. I wonder if it's because of the way most chickens are raised nowadays? I try to choose 'free range' chicken. Truthfully, I've always preferred fish to both dairy and poultry/eggs, but one is driven more and more into farmed fish because the wild variety is endangered, and I doubt that farmed fish has equivalent benefits. 

It would have been nice had this doctor summarized his presentation with recommended proportions of various foods–his own food pyramid. Does he think grains should be primary, or vegetables or fruit? Are they all of equal importance?

What I have trouble believing is that one has to go hardcore vegan to reap all the benefits in terms of the major killers, like CVD, cancer, diabetes, etc. And there are different forms of veganism. Living on Ramen noodles, potato chips, and softdrinks is vegan, but surely not wise eating. Here's where Macrobiotics had good suggestions: eat whole foods, mainly plant-based (with cereals at the center), and locally grown in season. True, its Achilles Heel was the reliance on too much salt, which we now know to be harmful, and it also unnecessarily avoided raw foods like the plague, which was not very logical, given adequate hygiene.

I like it! Democratic, rather than hierarchical. But what about nuts and seeds? Sea vegetables? Where do they fit? I don't know of any society on earth which consumes 1/4 of their food as beans (maybe some Indians or native Mexicans might approach this), so I'd lump nuts and seeds with beans and peas into the 'legume' category. Seaweed and mushrooms I guess could fit into the 'vegetable' category, as they are low in calories and nutritionally dense like vegetables.Do the proportions represent calories, e.g., eat 500 calories of fruit, etc. per day for a 2,000 calorie diet? Or do they represent volume? (I think calories would be more logical). 500 calories would be a lot of spinach, but then one would get its superior nutritional benefit.
Since I'm concerned about societal separation and inequality causing alienation, I'd prefer not to exclude animal food categories entirely. So I'd consider having five more or less equal categories: fruits, grains, legumes, and vegetables, plus animal foods: each accounting for about 400 calories in a standard 2,000 calorie diet. That would be completely balanced. If Americans only ate 20% of their calories as animal food, they'd be acting more like Japanese, and would live longer and suffer less degenerative disease. This is not to say that the ideal diet for humans could not be closer to absolute veganism, but it would be a good baseline. As it is, most of the world is consuming more and more animal food, harming both the health of the planet and that of humanity. We are going backwards…The arithmetic tells us that the greater the human population, the more vegan we must become, not less. But still, as Chris pointed out, there are places not really conducive to agriculture, where grazing is ideal, so I think there will always be a place for livestock. The problem isn't that we aren't vegan, it's that we eat too much meat (and dairy and fish). So lose the rigid categories and think of proportions instead. Someone like me who gets 10% of his calories from animal food resembles a vegan like you much more than I resemble a typical American that gets maybe 1/3 of his calories from animal food. In addition, you and I are probably a lot more health-conscious and careful about avoiding bad processed foods, and this is really what's most important to health.