What to expect this week:

The two pillars of our physical health are physical activity and diet. This week, we tackle the latter.

Almost 50% of the US population is obese.

60% of the foods we consume are ultra-processed.

Ultra-processed foods are linked to chronic non-communicable diseases like heart disease and cancer.

There has never been more food available to the human species, and the available food has never been worse for our health.

If these facts scare you, they should. The Standard American Diet (SAD) is killing people, and the Paleo Diet may serve as an alternative. Looking at the scientific evidence, we can see how this diet stacks up to its claims.

Housekeeping:

Train With Me

I’ve enjoyed building this small cult following around Evolve.2 so much. Having studied the concepts I’m now teaching for years, I’m so grateful for everyone who finds them interesting.

More importantly, these concepts aren’t just abstract ideas. The insights gained from studying human evolution are tools you can apply to your own life to improve your physical and mental health.

I want to extend these insights to you guys more directly than just the Evolve.2 platform. So, I’m now taking on clients for personal coaching/training. For the time being, due to my full-time job as an archaeologist, this will consist of only online coaching. However, I do see in-person training in the future.

Based on evolutionary insights, I will construct personalized programs for YOU. These programs will be centered on multifaceted fitness - the type of fitness our species evolved to achieve. This means building strength and muscle and improving cardiovascular health.

They will consist of 4-week programs incorporating the optimal amounts of resistance training and endurance work for your needs. I can adapt them to your time constraints or specific goals. After the 4 weeks, we’ll reassess and prep for the next 4. The months will get progressively harder as you become a more physically competent human being.

If this sounds like something you’d be interested in, DM me on Instagram or shoot me an email at this address [email protected] 

Also, check out The Bare Minimum for a small taste of what this type of training will look like.

Links to my e-Courses

• The Bare Minimum - FREE

• The Adaptive Scholar - $5

Paleo Diet (What it Gets Right and Wrong)

What is it?

Would you be happier and healthier if you stopped eating the food you eat every day, and reverted to the eating habits of your Paleolithic ancestors? The Paleo Diet suggests you would be. Here’s why.

“Paleolithic” translates to “Old Stone Age”, which refers to the time before humans developed plant and animal domestication. It spans from 2.5 million to about 10,000 years ago. The Paleo Diet is supposed to emulate the foods that our ancestors consumed during this period. 

The logic is as follows. Evolution is a relatively slow-moving process. For 2.5 million years, our ancestors hunted and gathered wild foods, which was enough time for their biology to adapt to those plants and animals, and our minds and bodies have mostly stayed the same since.

Our culture hasn’t, however. For the past 10,000 years, we have become more and more reliant upon domesticated plants and animals. For the past 50 to 100 years, we’ve become more reliant upon industrialized, processed foods. Accordingly, this has been too short of a period for our hunter-gatherer DNA to adapt to these modern foods. Many Paleo Diet enthusiasts claim that certain chronic non-communicable diseases like obesity and type 2 diabetes are the result of this mismatch between modern and ancestral diets.

The fix, according to these enthusiasts, is to adopt eating habits that resort back to those which our species spent most of its history eating and is presumably optimally adapted to.

Paleo Diet Food List

The foods you’re encouraged to eat on this diet include:

• Fruits

• Vegetables

• Nuts and seeds

• Eggs

• Lean meats, especially grass-fed animals or wild game

• Fish, especially those rich in omega-3 fatty acids, such as salmon, mackerel and tuna

• Oils from fruits and nuts, such as olive oil or walnut oil

Foods that are discouraged include:

• Grains, such as wheat, oats, and barley

• Legumes, such as beans, lentils, peanuts

• Dairy products, such as milk and cheese

• Refined and added sugar

• Added salt

• Starchy vegetables, such as corn, jicama, peas and white potatoes

• Highly processed foods, such as chips or cookies

Some books and nutritionists modify these lists and make small alterations but for the most part, these are the restrictions generally followed. 

The two main principles of this diet are that a.) these ingredients more closely resemble the eating habits of our Paleolithic ancestors and b.) abiding by it should be a healthier alternative to modern foods because our bodies are better adapted to said ingredients.

Let’s look at the science to see where the Paleo Diet lives up to and falls short of these claims.

What the Paleo Diet Gets Wrong

One of the defining features of the Paleo Diet is the exclusion of grains, like wheat and barely. The argument goes, up until 10,000 years ago, cereal grains and domesticated carbohydrates were absent from the human diet [1]. 

says Loren Cordain, one of the founders of the Paleo Diet movement.

But are grains truly that novel? Archaeological evidence suggests otherwise. 

There is an archaeological site called Ohalo II in Isreal, dating to around 23,000 years ago - about 13,000 years before the origin of farming. After being inhabited by hunter-gatherers as a temporary base camp, the site was quickly submerged by flooding, allowing its materials to stay preserved underwater. Initial excavations of the site uncovered brush huts and hearth features.

More recent research on the site has focused on the plant residue discovered. Archaeologists have looked at the botanical remains from the site and found wheat, barley, and oats [2]. More recent studies have shown that weeds that were present at the site are indicative of those that grow around cultivated grains, confirming the presence of cereal grains [3]. The authors of the latter study summarized the site by saying:

More archaeological sites that put a wrench in this anti-grain argument come from Bilancino II in Italy, Kostenki 16 Uglyanka in Russia, and Pavlov VI in the Czech Republic. Starch grains found on grinding stones have been recovered from all three sites, confirming that there was widespread consumption of these foods across Europe 30,000 years ago [4]. These pre-agricultural nomads were eating cereal grains.

Aside from archaeological evidence, we can look at the lifestyles of modern hunter-gatherers as a rough proxy for what our prehistoric ancestors ate. This literature brings a second concern for the Paleo Diet - variety. 

This is more of a misconception common amongst the general public than the professional advocates of the diet itself. In a nutshell, there is no single Paleo Diet. The diets of modern hunter-gatherers show large degrees of variation between groups [5]. Some groups rely more heavily on meat and fish, while others rely on fruits and honey. 

Most of this variation is due to geographic differences. People living in colder climates (higher latitudes) will rely more on animal foods, while those living in warmer climates (lower latitudes) will have more access to fruit. 

Additionally, many of these groups fail to show consistency in their own diets. For example, the diets of the Hadza change seasonally. The bulk of their calories come from honey during the wet season, and meat during the dry season [6].

To say that this or that combination of foods is the true Paleo Diet is to mislead us and contrary to the fact that “The only unifying features among hunter-gatherer diets are breadth and variability,” [6].

Last, is the idea that our bodies are strictly adapted to these pre-agricultural foods. While there is some truth to this, our bodies can adapt faster than we think. 

Milk consumption is an example of this. For most humans, the LCT gene which codes for lactase (the enzyme for milk digestion) is turned off by around 4 years of age. Those people grow up to be lactose intolerant and experience difficulties digesting dairy. 

But in certain populations of Europe and East Africa that gene persists into adulthood, allowing people to continue digesting milk. Geneticists believe that this is an adaptation that has emerged only since those populations’ ancestors began domesticating dairy-producing animals [7]. Within only a few thousand years, people become more efficient at consuming something that, historically, had ceased to be consumed by age 4.

That being said it is very unlikely that we will be adapting to MacDonald’s and Popeyes any time soon.

What the Paleo Diet Gets Right

What I think is the most important tenet of the Paleo Diet, and the one which has the greatest influence on your health is its emphasis on whole, unprocessed foods. This is by far the greatest difference in modern food from that of ancestral environments. Aside from the sheer quantity of food available today, its quality too has changed.

If foods that constitute the Paleo Diet can be roughly defined as whole foods that were present for most of human evolution then we can define processed foods as those that have been modified through the addition of ingredients like fat, sugar, and salt to fresh foods in recent years [8].

Importantly, there are degrees of food processing with some being more intrusive than others. The most extreme form is ultra-processed foods which are defined as [8]:

Researchers are beginning to converge on how widespread the problem of ultra-processed food truly is. First of all, roughly 60% of the American diet comes from this upper range of highly processed foods [9]. That does not include the moderate range of processed foods making up 15% of their diet. This is by no means a fringe issue. It's something that permeates throughout all of America and most of modern Western culture.

Second, the studies looking at the negative consequences of such eating habits are accumulating by the numbers. Here are just a few. 

Hypertension (or high blood pressure) is a serious medical condition that can lead to things like heart attacks and strokes. In a study of over 14,000 people who were initially hypertension-free, researchers investigated the effect of diet on their blood pressure after 9 years. They found a that “higher baseline consumption of [ultra-processed foods] was associated with a higher risk of incident hypertension” and that this remained significant even after controlling for other confounding variables [10].

Another significant contributor to heart attacks and the like is coronary heart disease, or the buildup of plaque in the arteries. A 2021 study has shown that this too is a greater threat for people consuming higher quantities of processed foods, making them 19% more likely to develop the disease than those who consume less [11].

A review of seventeen different studies found “substantial agreement” that ultra-processed food consumption is linked to a greater risk of general and abdominal obesity [12]. This is partly due to the fact that ultra-processed foods are hyper-palatable and easier to eat, leading people to eat more calories if given the opportunity - which has also been experimentally proven [13].  

There is even evidence of ultra-processed foods being associated with a greater risk of cancer. Studies show that these diets are correlated with breast [14], colorectal [15], and pancreatic cancer [16]. 

Hypertension, obesity, and cancer are three of the largest causes of mortality in the modern world, and it seems that our modern diets are a driving factor of all three.

Potential Benefits of the Paleo Diet

Given these conditions, could the Paleo Diet be effective in helping you achieve a happier, healthier life? 

The research looking into the efficacy of the Paleo Diet suggests it could and I’ll outline some of the key studies showing its positive effects. But before doing so, it should be noted that they do have some limitations such as smaller sample sizes and shorter study periods.

Nonetheless, these studies show improvements in various health markers. For instance, Frasetto and colleagues found that switching to a Paleo Diet led to significant reductions in blood pressure, LDL (bad cholesterol), and triglycerides (fat) [17]. 

Chronic disease is becoming more of a problem as we are living longer sedentary lives and the Paleo Diet may help with this as well. One literature review showed that multiple risk factors for chronic disease were mitigated by adopting this diet [18]. Many of the risk factors included those that were investigated in Frasetto’s study like blood pressure and cholesterol, in addition to blood sugar and waist circumference. 

Waist circumference and other body metrics can be predictors of chronic disease. A meta-analysis of randomized clinical trials looking at body weight, BMI, and waist circumference found that adopting a Paleo Diet can improve all three metrics [19]. 

One of the scariest chronic diseases, which we all know someone who has suffered from, is cancer. A 2023 study found that people consuming a Paleo Diet were less at risk for developing colorectal cancer [20]. Note how this is one of the cancers that have been linked to eating more processed foods. 

Again, these studies are by no means the be-all and end-all. They are simply the data we have now looking specifically at the potential health benefits of the Paleo Diet. Even they recognize that further research is needed to develop more firm conclusions. 

We can safely say that the modern, processed diets plaguing industrial nations are unequivocally inferior in terms of health to a diet consisting of unprocessed whole foods. 

This is the key insight we can gain from the Paleo Diet Movement. Whether you want to adopt it strictly, add a few grains here and there, or you want to take a shot at a completely different diet, it is the ultra-processed foods our ancestors never had access to that you should avoid. They are leaving us with lives of morbidity. 

References: 

[1] Cordain, L. (1999). “Cereal grains: humanity's double-edged sword.” World Review of Nutrition and Dietetics 84:19-73.

[2] Nadel, D., et al. 2012. “New evidence for the processing of wild cereal grains at Ohalo II, a 23 000-year-old campsite on the shore of the Sea of Galilee, Israel.” Antiquity 86(334):990-1003

[3] Snir, A., et al. 2015. “The Origin of Cultivation and Proto-Weeds, Long Before Neolithic Farming.” PLoS One 10(7):e0131422.

[4] Revedin, A., et al. 2010. “Thirty thousand-year-old evidence of plant food processing.” Proceedings of the National Academy of Sciences 107(44):18815-9

[5] Pontzer, Herman, et al. 2018. “Hunter-gatherers as models in public health.” Obesity Reviews 19(1):24-35.

[6] Pontzer, H. and Wood, B. 2021. “Effects of Evolution, Ecology, and Economy on Human Diet: Insights from Hunter-Gatherers and Other Small-Scale Societies.” Annual Review of  Nutrition 41:363-385.

[7] Tishkoff, S., et al. 2007. “Convergent adaptation of human lactase persistence in Africa and Europe.” Nature Genetics 39:31–40.

[8] Gupta, S., et al. 2019. “Characterizing Ultra-Processed Foods by Energy Density, Nutrient Density, and Cost.” Frontiers in Nutrition 6:70.

[9] Poti, J., et al. 2015. “Is the degree of food processing and convenience linked with the nutritional quality of foods purchased by US households?” American Journal of Clinical Nutrition 101(6):1251-62.

[10] Mendonça, R., et al. 2017. “Ultra-Processed Food Consumption and the Incidence of Hypertension in a Mediterranean Cohort: The Seguimiento Universidad de Navarra Project.” American Journal of Hypertension 30(4):358-366.

[11] Du, S., et al. 2021. “Higher Ultra-Processed Food Consumption Is Associated with Increased Risk of Incident Coronary Artery Disease in the Atherosclerosis Risk in Communities Study.” Journal of Nutrition 151(12):3746-3754.

[12] Mambrini, S., et al. 2023. “Ultra-Processed Food Consumption and Incidence of Obesity and Cardiometabolic Risk Factors in Adults: A Systematic Review of Prospective Studies.” Nutrients 15(11):2583.

[13] Hall, K., et al. 2019. “Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake.” Cell Metabolism 2019 Jul 2;30(1):67-77.e3.

[14] Fiolet, T., et al. 2018. “Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort.” BMJ 360:k322.

[15] Shu, L., et al. 2023. “Association between ultra-processed food intake and risk of colorectal cancer: a systematic review and meta-analysis.” Frontiers in Nutrition 10:1170992.

[16] Zhong, G., et al. 2023. “Ultra-processed food consumption and the risk of pancreatic cancer in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial.” International Journal of Cancer 152(5):835-844.

[17] Frassetto, L., et al. 2009. “Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet.” European Journal of Clinical Nutrition 63(8):947-55.

[18] Manheimer, E., et al. 2015. “Paleolithic nutrition for metabolic syndrome: systematic review and meta-analysis.” American Journal of Clinical Nutrition 102(4):922-32. 

[19] de Menezes, E., et al. 2019. “Influence of Paleolithic diet on anthropometric markers in chronic diseases: systematic review and meta-analysis.” Nutrition Journal 18(1):41.

[20] Xiao, Y., et al. 2023. “Adherence to the Paleolithic diet and Paleolithic-like lifestyle reduce the risk of colorectal cancer in the United States: a prospective cohort study.” Journal of Translational Medicine 21(1):482.

Fit Fuel Song Suggestion

The Fit Fuel song suggestions are hand-picked by yours truly to elicit the motivation (and possibly aggression) needed to initiate or persist through a grueling workout. They consist of heavy, brutal guitar riffs and gruesomely guttural vocals. Additionally, I timestamp what I believe to be the best riff of the song - one that will kick your nervous system into overdrive when approaching a personal record (PR).

(If this song isn’t already on your workout playlist, you should be ashamed of yourself.)