Brain Food

Abstract

The lore and the science that recommend the eating of fish as brain food can be traced to the discovery in 1719 of a high content of phosphorus in our brains, which eventually led to the proposal of Jacob Moleschott in 1852 that there could be ““no thought without phosphorus.”” Louis Agassiz added to this the knowledge that fish, like brains, were also rich in phosphorus, and speculated that the eating of fish might improve intelligence. Mark Twain ridiculed the assertion in 1871 in a widely published humorous letter to an aspiring author that nevertheless favorably popularized the notion. We now know that the large amount phosphorus in brain is due to a high concentration of phospholipids, structural molecules of cell membranes and interconnections, such as the axons and dendrites of nerves. A dietary requirement for phosphorus was, however, not substantiated. Nutritionist's and biochemist's attention are now drawn to certain fatty acids present in phospholipids that are termed ““essential,”” meaning they cannot be biosynthesized and must therefore be derived from the diet. Eating fish and other ocean and fresh water food products is recommended based on their content of EPA and DHA, members of the omega-3 family of essential fatty acids. The omega-3 fatty acids interact with the omega-6 family of essential fatty acids, which predominate in land-based food oils. The complex interplay of the two fatty acid families relates not only to their critical presence in our cell membranes, but also in body regulatory processes via chemical messengers derivatives, the eicosanoids. An optimal ratio of our dietary intake of omega-3 to omega-6 fatty acids is deemed important for normal development of the nervous system as well as for optimizing many health-related cardiovascular and immune system functions.