Monday, August 8, 2011

The Woodstock of Evolutionary Medicine (Part One): 72 hours of awesome.

This past weekend, I spent three days on and around the campus of UCLA for the first (but hopefully not last) Ancestral Health Symposium – a gathering of researchers, teachers, bloggers, and enthusiasts who take an evolutionary biology approach to understanding the impact of nutrition and lifestyle on human health. Over 50 speakers presented talks and posters on topics such as the optimal human diet, fitness from an evolutionary stand-point, how to evaluate scientific “discoveries” presented in the media, the impact of a produce-based diet versus a grain-based diet, and specific biochemical pathways of disease.

I was lucky enough to attend the symposium as part of the interview team. Our dedicated journalists and camera crew managed to interview almost every speaker! It was a grueling few days – we started work at 7am and didn't head to dinner until 9pm – but every minute was worth it! In the coming weeks, all of the presentations will be posted online along with our interviews. I'll be sure to link to them as they become available. In the meantime, I'll give you an overview of what I learned at the symposium (this post) and the amazing presenters I was lucky enough to interview as part of a continuing series.

Here's a list of the people I interviewed:
I also had the pleasure of meeting some of the big names in the Paleo diet community including Robb Wolf, Gary Taubes, Denise Minger, Mark Sisson, Tom Naughton, and co-organizer Adam Blaidsdell. What a welcoming and inspiring community!

The original human diet.

Before I get into all the information presented at the symposium, let me give you a brief overview of human health and how it has changed with time. I promise to provide more details and references when I get to the specific presenters, especially when I discuss doctor and medical researcher Staffan Lindeberg and anthropologist Mark Nathan Cohen. You can also read about their findings in the following places:
Agriculture is a relatively recent human invention. Before that, we were hunter-gatherers (HGs) who survived on a diet of mainly animal proteins and fats, vegetables, fruits, and nuts. The average life span of HGs (i.e. life expectancy) was only about 30 years, but that was mainly due to infant mortality, lack of modern medicine to treat infections and injuries, and a rather high likelihood of being eaten by a lion. Hunter-gatherer communities had many elderly people, and their skeletal remains indicate a lack of many diseases we attribute to old age in our modern society. Studies of the few remaining primitive communities have also shown a lack of the so-called “diseases of civilization” including diabetes and obesity, cardiovascular disease, high blood pressure, stroke, dementia and Alzheimer's, cancer, osteoporosis, and auto-immune disease. Within a primitive tribe in Papua New Guinea – the Kitavans – about 6% of the population is over age 65. These people are very healthy and those who survive to age 45 have similar life expectancy to people in modern societies.

Our ancestors were much healthier during their hunter-gatherer years than after making the switch to a grain-based agricultural diet. Post the advent of agriculture, humans lost several inches in height and began developing these new diseases that had not been present in their ancestors. Disease and death were not only due to the change in diet but also the changes in lifestyle. Agriculture required communities to settle, leading to higher population density and more communicable disease, and the potential for conquest. Life expectancy actually went down post-agriculture. In the 1800's, for example, the life expectancy in Ireland dropped to only about 20 years and was even lower for certain societal classes. Only in recent decades has life expectancy increased, mainly due to medical advances and a safer environment, and we have finally returned to our pre-agriculture size.

Understanding why agriculture led to poorer health outcomes than the hunter-gatherer lifestyle is the main goal of the ancestral health community. Of the many presentations and conversations I was involved in throughout the symposium, there were several points of agreement within the community.

What I learned on my summer vacation.

1. A modern day, grain-based, processed food diet is a major contributing factor in most of the diseases we attribute to old age or random chance, including (but not limited to) dementia and Alzheimer's, cardiovascular disease, high blood pressure, arthritis and other inflammation, cancer, osteoporosis, PCOS, IBS and other digestive problems, and auto-immune disorders like multiple sclerosis, Celiac disease, lupus, and fibromyalgia. Of course, diet is the main contributing factor to obesity, Type 2 diabetes, and other metabolic disorders. These diseases do not appear in modern day hunter-gatherer tribes, and to the extent that they can be diagnosed from skeletal remains, there is no evidence that our pre-agricultural ancestors suffered from any of these diseases.

2. A diet that includes only whole foods – vegetables, fruit, pasture-raised meat and eggs, seafood, and nuts – is the diet to which humans are best adapted. The optimal human diet does NOT include gluten (a protein found in wheat, barley, and rye), added sugars, vegetable oils (especially corn and soybean) and most dairy products. Beans, peanuts, and lentils should be minimized or avoided due to these plants' natural defenses against being eaten. Whether or not you eat meat, a grain-based diet is bad for you and for the environment.

3. Getting fat is not caused by eating fat. Breaking the body's natural processes for controlling appetite, absorbing nutrients, and storing/accessing energy in the form of fat is what causes people to gain weight and struggle to lose weight. Therefore, regulating your insulin response is a key factor in overall health and wellness.

4. The specific break-down of foods and macronutrients that lead to optimal health may depend on your heritage and current state of health. For example, someone who's ancestors hail from Sub-Saharan Africa may be better adapted to certain foods than the descendants of, say, Scandinavians. Also, a person with metabolic syndrome – obesity or Type 2 diabetes – may require a stricter diet in order to restore insulin sensitivity.

5. Whole grains are NOT healthy. There are no nutrients you can get from grains that you cannot get from vegetables or fruit, and gluten is toxic to humans.

6. Sugar used to be a scarce and precious commodity; now it is prolific. Whether in the form of high fructose corn syrup, table sugar, agave nectar, honey, refined grains, or alcohol, sugar is a dangerous substance that must not be over-consumed. Always eat your sugars with fiber, such as in the form of fruit. Do not eat fake sugars. Do not drink sugar.

7. If you have unexplained digestive problems (e.g. bloating, constipation, diarrhea, or heart burn), skin problems including acne or rosacea, auto-immune disorders, metabolic syndrome, or unexplained pain or stiffness, you should seriously consider changing your diet. Meeting with a holistic medical practitioner, especially one who specializes in nutrition and health, may help you with your recovery.

8. Ancestral health is a useful approach to studying human health and wellness. However, “because cavemen did it” should not be the only metric by which we determine the impact of any particular behavior. Scientific investigation into why certain ancestral behaviors were more beneficial than modern ones is essential to improving human health.

9. Lifestyle behaviors such as sleep, stress, and movement are important contributing factors in human health and well-being.

10. Poor people, especially those relying on food stamps, WIC, or other government services are ill-served by the USDA's nutritional advice to eat whole grains and low-fat meat and dairy. Also, adhering to a healthy ancestral diet may be out of reach for many people, due to cost, time to buy and prepare foods, limited access to unprocessed whole foods, and lack of nutritional and/or culinary knowledge.

Beyond these main conclusions, there are several issues still being debated within the ancestral health community such as:

  • How much protein/meat/starch/fruit should people eat? Is there one set of guidelines that will work for everyone, or do people need to experiment to find an optimal diet?
  • Conventional, low-fat dairy has been linked to auto-immune disorders and other health problems. Is raw/whole/pasture-raised/fermented dairy equally harmful?
  • What are the key studies that need to be done to advance our understanding of nutrition, lifestyle, and human health?
There was a ton of information packed into only two days of talks, but there were a few topics that were absent or seemed under-developed. The only specific food I didn't hear much about was soy. Fermented soy was briefly mentioned as having positive health benefits, and soybean oil was definitely labeled as bad. Corn and soybeans dominate the vast monocrop industrial farms that demand scarce resources and pollute the environment, so there are solid ethical reasons for avoiding these products. However, I would have liked to hear more about the health impacts of different soy products such as edamame or tofu versus soy milk or soy lecithin.

The majority of the symposium focused on why/how certain behaviors contribute to better or poorer health and how to implement positive practices into modern life. Other than additional research, I didn't come away with a strong sense of what needs to be done to disseminate this information and help more people modify their diets and lifestyles. How can the ancestral health community connect with members of other communities (e.g. sustainable agriculture, global food and poverty, or policy advocacy groups) to achieve common goals such as moving away from grain-based agriculture or revising nutritional standards? What policy changes should the community be advocating for, and how do we mobilize people to make these changes?

If the goal is a healthy human population, in which an ancestral diet is widely accessible and sustainable, what are the steps needed to achieve that goal? If we prioritized polycultures, how many people could we feed a Paleo diet? Given that this is a blog about sustainable food systems, this last point is the one I want to focus on in the future. Although produce plays a big role in ancestral diets, most Paleo diet cookbooks and blogs advocate getting the majority of your calories from animal products. Of course, this has implications for sustainability because the volume of meat that can be produced in a sustainable and ethical manner may be limited. However, author and presenter Don Matesz suggested that humans may not need to eat quite as much meat as some Paleo proponents advocate and, furthermore, he thinks too much meat can also lead to health problems. I'll go into more detail later, but I was very encouraged by my discussions with Don. A diet in which meat and seafood are consumed only on a weekly basis rather than every day or at every meal may still be healthy insofar as you can get enough iron and B12 eating this way. Getting enough protein may require more eggs, seafood, or meat especially since beans and lentils can cause digestive problems and should be consumed only in moderation if at all. Even nuts and nut butters should probably be limited to a few servings per day. A low-meat diet with perhaps more ethical eggs and seafood, supplemented with some lentils and nuts, sounds like the best option for me.

If you are interested in learning more about a Paleo/ancestral diet, be sure to check back for more posts in this series and links to the presentation/interview videos. Also, check out the following websites:
For more on why sugar is especially bad for humans, watch Sugar: The Bitter Truth, by medical researcher and symposium presenter Robert Lustig.


  1. Hmm...who's this Adam Blaidsdell fellow?

  2. I think he's the guy who gave me a cold! : )

    In all seriousness, though, thank you so so so much for putting the symposium together. I've been to a LOT of conferences, and this one tops the list. Everything went so amazingly well. I'm still busy chatting and sharing links with all my new friends. If there *is* an AHS 2012, you can put me down for the interview team for sure!

    Also, perhaps you should consider getting Vibram to sponsor it; I've never seen so many Five Fingers in one place at one time!

  3. This is one most easily digestible articles on Paleo I've read in a while. No pun intended! :-)

  4. There will be an AHS 2012 for sure. Would be great to have you back on interview and photo duty again. :)

  5. Thanks for this post and serving on the interview team. Perhaps next year we'll have the chance to connect.

    Peter Ballerstedt
    Grass Based Health

  6. On one hand there many older people. On the other hand they had a life expectancy of 30. Which is it?

    I would assert that their immune systems were perfectly able to fight off any infection. Of what use is it otherwise? The necessity of antibiotics was a result of eating agricultural foods and the sanitation issues from the resulting density of population. Same with infant mortality--a byproduct of agriculture.

    And being eaten by a lion assumes everyone lived in Africa. It's possible at first, but eventually there were people living in temperate climates, so this was not necessarily a major contributor to death. My guess, also, is that our larger brains would have enabled us to learn how to avoid being an animal's dinner.

    Injury, sure, but being hunter-gatherers I would imagine they had heightened awareness of their surroundings making klutzy moves less likely. I think living to be elderly was the rule rather than the exception.

  7. Dear Mr. Trashcan,

    "On one hand there many older people. On the other hand they had a life expectancy of 30. Which is it?"

    Actually, both can be true. Imagine following a group of 10 babies throughout their lives. If 5 of them die at birth (age 0) and 5 live to be 60 years old, the average life span (life expectancy) of the group would be 30 even though half the people lived to "old" age. If all 10 babies had lived to age 30, the life expectancy would also be 30 years. Life expectancy is the same thing as average life span, and it doesn't tell you anything about the number of elderly people in a given population.

    Hunter-gatherers had higher rates of infant mortality than we do today, lived higher risk lives (the lion was just one example), and did not have modern medicine (which combats diseases caused by agriculture as well as other kinds of problems). That means more people died young compared to modern populations, which makes our life expectancy higher than that of hunter-gatherers. There still were old people, though, and they were generally healthier than our old people.

    Hope this clears things up! Thanks for commenting.


  8. Peter - We did connect! I came by your poster on Saturday to talk about the importance of polyculture farming systems, especially those that integrate pastured livestock. You were pretty popular, though, so I understand if you don't remember.

    Grass-fed beef... YUM.

  9. It seems everyone has a different opinion of dieting and which diets really work versus the "short term weight loss" diets. By short term weight loss , this refers to the phenomena where every pound that was lost comes right back on due to sheer hunger after starving your body for so long. Starvation diets are definitely not the way to go, but there are some excellent lower calorie diets that will leave you far from starving - and keep the pounds off for a lifetime.

    D3 5000 Fields of Flowers