Have not read the Pollan’s book. But may be we are using different scales here?

I by no means doubt the validty that omnivorous would be better for the body. I question the data points available to study the effect of food on the mind.

It also occurred to me that the following may be considered a valid data point:

All carnivorous animals: Lions, Tigers etc are violent in nature with an agitated mind, whereas all the herbivores such as the Elephants, deers collectively are far more calm and composed, living peacefully.

(Before someone jumps on me, let me clarify that I’m not suggesting that Food is the only reason carnivores are violent. I’m providing data point that carnivores are collectively far more violent and herbivores are calm and composed. If it were entirely independent, may be we could have found a calm carnivore and a violent herbivore.)