When I used the so-called Paleolithic paradigm to guide my approach to nutrition, I embraced the idea that we (humans) have a ‘need’ to eat grass-finished meat and wild fish to get adequate amounts of long-chain omega-3 fatty acids, particularly EPA and DHA, for cardiovascular and neurological health respectively.
Like other supporters of this idea, I believed that lack of animal sources of these fats would cause depression, schizophrenia, attention deficit, and poor intelligence. It all ‘made sense’ based on the hypothesis that meat-eating provided the crucial energy and fatty acids that supported human brain evolution.
After some time I realized this hypothesis ignores the fact that meat provides only fat and protein, while the nervous system prefers glucose. The human brain uses about two-thirds of the glucose used by the entire body. Meat simply does not provide the best fuel for the brain. I now tire of reading anthropologists arguing that meat must have 'fueled' brain expansion because of its rich provision of fats. If they took a moment to study neural cell energy metabolism, they would realize that the expanding human brain needed a steady supply of non-toxic glucose (i.e. glucose not derived from protein), not found in meat or fat.
About eight months ago when preparing my presentation for the Ancestral Health Symposium I recalled that I had previously seen evidence challenging the hypothesis that humans need preformed EPA and DHA for healthy nervous system development and function.
That evidence consisted of studies showing that although vegetarians have essentially no intake of these preformed omega-3 fatty acids, they do not have deficits of cognitive or neural function.
Do vegetarian children suffer poor development of intelligence, and do vegetarians in general suffer any disorders that could be attributed to lack of preformed omega-3s? Read more....