Even the most ardent vegetarians will begrudgingly admit that meat eating played a large role in the evolution of early man (although now we’re somehow expected to totally revert back several million years). Including calorie-dense meat in our diets allowed us to ditch the larger guts used for digesting inefficient plant matter, and we developed big brains. We were able to consume more nutrients and more calories without sacrificing mobility, and eating meat allowed man to spread to harsher climes, where vegetation was sparse or only seasonal. The human brain requires an incredible amount of energy to run, and meat was the most readily available source of sufficient fuel.
But perhaps the shift from vegetarianism to meat-eating isn’t the only explanation for the considerable increase in brain size and function. Harvard’s Dr. Richard Wrangham suggests that the advent of cooking played a major role in increasing the availability of brain fuel for our ancestors. Cooking changes food in three important ways, according to Wrangham: it “unfolds” the amino-acid chains of proteins, making it easier for digestive enzymes to process them; it makes starches more digestible; and it “physically softens” food, effectively allowing us to get more calories in with less work. Cooked food is no more calorific than raw food, but it takes fewer calories to process and digest.
Wrangham has assembled an impressive line of evidence. From studies with patients using intestinal collection bags, cooking appears to increase the absorption of food in the stomach and small intestine from 50% to 95% when compared to raw. Rats fed softer, pre-processed food pellets gained 30% more weight after 26 weeks than rats fed the same amount of standard pellets (not exactly cooking, and these are rats, but it makes his point that pre-processed/cooking allows for easier absorption). Our taste receptors are engineered to “prefer” softer food, because that means easier digestion and more calories with less work – perfect for Grok, or for anyone who has to really work for his or her food (rather than just stroll down to the grocery store).
Of course, he goes on to suggest that what was a boon to early man has become a curse and scourge to modern man (I like this guy!). Too much of a “good” thing has its definite drawbacks, and the prevalence of processed, pre-packaged “soft” food that easily digests has coincided with rising obesity rates, which come with a whole host of lovely complications of their own. See, our taste receptors and predispositions worked well when sugar and refined flour weren’t readily available. Grok loved sweets, but fruit wasn’t nearly as sweet as the commercially grown fruit we eat now.If Grok had access to Twinkies and canned fruit drenched in syrup, he’d probably go for it too, develop diabetes, and get fat (just look around you for ample evidence).
We need more researchers like Wrangham. It’s obvious his is a labor of scientific inquiry; he doesn’t set out to further an agenda (unless that agenda is anthropology). Detractors could look at my post and say, “Oh, it’s just pro-meat, low-carb Sisson trying to justify his stance again” (no matter that we always back our posts up with studies and facts). But Wrangham is a professor of anthropology whose frank assessment of our country’s obesity issues is merely a natural offshoot of his science, and that can’t be ignored. Let’s hope more people pay attention. It’s easy enough for those in denial to dismiss the ideas of a Taubes or an Eades as “agenda-driven,” but it’s tough to ignore similar ideas when they come from someone without a dog in the fight.
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.