Very Recent Genetic Adaptation

A genetic adaptation to high altitude present in Tibetans is probably only about 3000 years old. On the evolutionary timescale...that's nothing! 

Growing up I was a taught creationism, which is roughly the idea that evolution didn't happen because God created everything as it was written in Genesis. When I did learn about evolution though, it was clear to me that it was real and happening now. One of the books that had a big influence on me was The Beak of the Finch: A Story of Evolution in Our Time, which is the amazing story of major genetic adaptations observed by scientists in the Galapagos over a span of mere decades.

Lactase persistence, the ability in adult humans to digest milk, is another famous recent human genetic adaptation. I suspect we will discover more and more of these.

Does that invalidate the evolutionary nutrition concept? No, because properly as a concept it's not about imitation, but about evaluation. Yesterday I was thinking "What if I still believed in creationism? Would I still eat this diet?" Either way, there is plenty of evidence out there for NOW in modern humans that the lipid hypothesis is bunk (see Good Calories Bad Calories) and that foods like gluten are hardly good for you (gluten linked to schizophrenia as an example).

So what use is evolutionary nutrition? It provides a further framework for questioning and evaluating foods. I might have never questioned the role of gluten in my diet if I hadn't awoken to the idea that our ancestors didn't eat grains...and did better than fine. But I'm also saying that there is plenty of evidence to eat this way outside the evolutionary evidence.

As for that, we shouldn't be afraid to question it as well. Is every food in the fossil record nutritious? Cycads anyone? And is every one that isn't the epitome of evil? That's why I sort of like Cordain's newsletter- when he is taking down neolithic foods, he provides an extensive bibliography- though unfortunately a lot of it is extrapolation of test tube in-vitro science, not actual studies of humans. I would love to see more of those. His recent series on the evils of nightshades was ultimately fairly unconvincing to me, because well...yeah, they have some chemical compounds that are questionable....but name a plant that doesn't! Let's not underestimate the human capacity to detoxify- it's why we have several robust organs to do so.

And several of the in vivo studies he cited to prove potatoes are questionable are questionable themselves-" Two recent human studies have shown that high potato diets increase the blood inflammatory marker IL-6" cites this study- "Chronic intake of potato chips in humans increases the production of reactive oxygen radicals by leukocytes and increases plasma C-reactive protein: a pilot study." That's not potatoes! It's potatoes fried at very high heat in rancid PUFA-infested oils. Ack.