Peter Turchin, advocate of Cliodynamics, has posted on his recent success in adopting the “paleo diet”. The diet is based on the food presumably eaten by our evolutionary ancestors in the Paleolithic era, which is before the dawn of agriculture. Lots of meat, fruit, vegetables and nuts, but no grains.

Although I have much sympathy for the paleo diet for its health benefits (its largely how I eat), I’ve always thought the paleo label was not quite right. Turchin raises this point:

When I explain to friends that I don’t eat any cereals or grains, legumes, or dairy, a frequent reply is – “what’s left?!” Actually, a lot. All kinds of meat, any seafood, eggs, all kinds of fresh vegetables (salad type – lettuce, tomatoes, cukes, radishes, green scallions, cilantro, peppers), other vegetables (all varieties of cabbages, numerous kinds of squash, avocado, olives, asparagus, onions and leaks, spinach), root vegetables (potatoes, yams, carrots, root parsley, yucca, and a number of others I haven’t explored yet), fruits and berries and nuts. No caveman ate the kind of varied diet that we can obtain by an easy trip to the supermarket. So the ‘paleo diet’ is a complete misnomer.

A bigger issue, however, is the evolutionary interpretation of the paleo diet. Evolution is about reproduction, not health. That is why agriculture came to dominate the world despite the initial hit to health that resulted. And even if the paleo diet is the healthiest diet and we are well adapted to it, there is no rule of evolution that says it cannot be improved on. Turchin writes:

Additionally, there is no particular virtue in eating an undomesticated variety, compared to a domesticated one. In particular, I suspect that wild rice is probably worse for you than white rice. Both are grass seeds, and so poisonous by definition. But with the domesticated rice there is at least hope that the most poisonous varieties have been selected out (although it is not a certainty). Interesting how an evolutionary approach makes you look at things from a very different angle.

And this is before we consider recent human evolution - compare the ability to digest grains and alcohol between groups with varying histories of agriculture, and we get very different results. Again, steering clear of rice or grains may be the better health option, but evolution has changed the equation from what it once was.

I prefer the example of tomatoes - sourced from South America, not consumed by out ancestors on the African plains, but they are a core element of many paleo diets. I would suggest the tomato eaters are better off for it. When our hominid ancestors started to eat meat, did a group of them refuse to join in as they preferred to eat the “Pliocene diet”?