The Role Of Good Brain Foods In Human Evolution

If you believe anthropologists, sometime in the mists of early human development, we diverged from other primates on the evolutionary tree.  Among other things, that change led to our current human brain.  Weighing in at 2% of our body weight, the size of the human brain is about twice that of our closest relatives.  But that increased size comes at a hefty price, since the brain consumes 20% of the body’s energy.  It also hints at things to come about our body composition.

One has to wonder how early humans managed to gather enough good foods for the developing human brain.  Things would have been harsh, so spending the energy to support something that provided intelligence, rather than speed or stamina, would have been a tough order.

What Foods Are Good For The Brain?

Most experts agree that when it comes to intelligence, size matters.  If we accept the idea that early hominids gained a competitive advantage through increased brain size, one must wonder how they were able to support those kinds of energy demands.  The diet to support the growing human brain must have been dramatically different from that of other primates, since brain cells require twice as much energy as other cells in the body.

A recent finding suggests that fats may have been the source of that energy.  Even though there’s a bias against fats in today’s society, they are more energy dense than carbohydrates or protein, so it might make sense.  Anthropologists found fossils of stone tool fragments together with bones of turtles, crocodiles, and fish.  This would have given early humans a diet much different than our smaller-brained primate cousins, who consumes primarily fruit, vegetables, and insects.  More energy to support the developing human brain.

German anthropologists have also conducted studies in mice that support the idea that the transition to a higher protein, higher fat diet may have provided foods good for the developing human brain.  Their research indicated how changes in diet may even affect gene expression.  Even the type of fat consumed was shown to make a difference, with a high sugar, high saturated fat diet (think McDonald’s) exerting a negative influence on brain function.  Some evidence even suggests that eating fats may even help reduce seizure activity.

Even the composition of the brain suggests the importance of fats for good brain health.  The brain weighs in at about 77% water, 12% lipids (fat), and 8% protein, with the remainder being carbohydrates, salts, other organic substances.

It all suggests that the evolution of our brains required eating a high fat diet to provide a competitive advantage.  We need fats for good brain health.  Specifically, omega-3 and omega-6 fatty acids.  Omega-3′s are abundant in cold-water seafood, leafy vegetables, and walnuts.  Omega-6 fatty acids can be found in most nuts and seeds.  All great foods for the brain.

None of this discounts the importance of high quality sources of carbohydrates in brain health.  Fats can’t cross the blood brain barrier, so glucose is the only source of fuel for the brain, and high quality carbohydrates from fruits and vegetables readily meet this need.  But the need for glucose is also the reason many people who switch from a high carbohydrate diet to a high fat diet report experiencing several days of confusion, as the body moves to produce glucose by gluconeogenesis.

One must believe that the bias against fats due simply on the basis of calories would have negative consequences over the course of a lifetime.  There’s ample evidence to support the idea that humans evolved to consume high quality fats, since they play a vital role in so many processes within the body.