Tuesday, February 12, 2013

Clueless Experts on the Evolution of Human Nutrition

This is an interesting post in many respects: "Experts on the evolution of human nutrition", but it also displays the utter cluelessness of academics when it comes to applying what should be useful knowledge to a real-world problem.
"Want to eat a diet that mimics that of our Paleolithic ancestors? It might be a little more complicated than what the popular books say. "The fact is, there was never one Paleo Diet; it's more likely there were hundreds of them and that they were continually changing and broadening over evolutionary time.

"That was the overarching takeaway message of an impressive lineup of experts on ancient human diets at a symposium entitled "The Evolution of Human Nutrition" organized by the Center of Academic Research and Training in Anthropogeny (CARTA) at UC San Diego on December 7, 2012...."
That's not particularly useful as a takeaway message, although I guess it's useful to an academic's career: "Things are complicated, they need more study, which I'd be happy to do..."
"...President of the Wenner-Gren Foundation for Anthropological Research Leslie Aiello, who chaired the symposium, expressed some amusement over folks who aspire to the great lengths of trying to live like cavemen in the big city.

"However flawed their premise, she noted, the gaining interest into the diet of our ancestors was one to be welcomed. After all, it could lend clues into current causes of epidemics of obesity, type-2 diabetes, and cardiovascular disease...."
The mind reels. Clearly the Chair of this symposium doesn't know enough about the "Paleo Diet" to know that it not only will "lend clues" about the "epidemics of obesity, type-2 diabetes, and cardiovascular disease", but it often resolves them. And there's not only countless anecdotes to that effect, but actual research studies. Guess she doesn't read those journals. But maybe I'm unfair, I mean, not everyone can be an expert on the Paleo Diet... Oh wait. She is supposedly an expert on the Paleo Diet. Time to do some homework, professor.

Moreover, she points to the old NY Times article featuring John Durant and Melissa McEwen. John cured his obesity with the Paleo Diet, and Melissa cured a chronic digestive condition that had a huge impact on her life. How is that "flawed"?

John describes the Paleo Diet thus:
"Followers of the paleo lifestyle argue that the agricultural revolution led to a marked decline in health, in part due to less diverse sources of nutrients. “Our diet became very narrow, very quickly. We went from eating a wide variety of animal foods and plant foods driven by seasonal eating, to a very narrow set of foods.”"
So is this in marked contrast to what these "experts" have to say?
"...By 15 to 10,000 years ago, modern humans had taken over the landscape and were already shifting from foraging to farming, which represented a major transition in the human diet, Schoeninger said.

"The shift was was one from a varied, broad diet that changed with seasons to be replaced with one that included specific plant foods such as cereal grains as a dietary staple, according to anthropologist Clark Spencer Larsen.

"This reliance on single foods such as grains as staples with characteristically low nutritional quality, along with more availability of food and more sedentary lifestyle, he said, was the start of health decline as evidenced by study of bones and teeth of the era...."
So, the obvious conclusion, to me and to John, is to eat like the healthy folks. That's the "Paleo Diet".
"...Barry Bogin, a biological anthropologist of Loughborough University, UK, has witnessed this sort of population health decline first-hand while studying the Maya who in recent years have made the switch from their traditional varied diets to ones that are more modern and containing a great deal more animal products, cereal grains, and added sugars...."
Yes, OK, we get it. Clearly we should eat like the healthy people, right?
"...But when asked about dietary advice (including what food groups to be consumed and to not be consumed) that can be gathered from an extensive knowledge of evolution of the human diet, Ungar simply shrugs and responds, "I tell people to go see a nutritionist.'..."
The nutritionists will tell you to eat the food pyramid, which reliably causes "obesity, type-2 diabetes, and cardiovascular disease." That's not very good advice, but it is the advice that has led to 60% of Americans being overweight.

I get the feeling that some of these folks are a bit peeved that they didn't draw the conclusion that was so obvious to Dr. Eades and the other innovators in the Paleo Diet. Some, like Ungar, just don't know what they're talking about. They're criticizing the Paleo Diet community without having any idea what members of that community are actually saying, and without any idea of the health benefits that have already been demonstrated in those who follow the Paleo Diet.

That's just clueless. But again, it's an interesting post, and there are some videos of the talks at the original link.