Feeding your brain: Omega-3 and Omega-6 fats

Our diet supplies the basic building materials and energy that form the foundation for good health. As is commonly pointed out, over the last 100 years our diet has changed hugely from what would be considered a ‘natural’ human diet with increasingly severe effects on our bodies. Probably the two major changes in our diets have been the massive increase in sugar intake and the huge change in the types of fats we eat. In this post I want to touch briefly on the role of fat.

Research shows that the ratio of different fats that we eat is critically important. It seems likely that humans evolved on a diet that had about a 1 to 1 ratio of omega-6 to omega-3 essential fatty acids but over the last 100 years or so this ratio has changed dramatically to 15-16 to 1 (ie. we’re eating 15 times as much omega-6 as we are omega-3). In fact some studies put this ratio as high as 30:1.

It’s fairly certain that this massive change in our diet is contributing to many of the modern health epidemics- cardiovascular disease, cancer, autoimmune and inflammatory diseases have been linked to the ratio of essential fatty acids in the diet. It also seems likely that many of the health benefits of following a ‘Mediterranean’ or ‘Japanese’ diet come down to the fact that these diets have much better fat ratios that a standard western diet.

Your brain is composed of 60% fat so it makes sense that getting enough of the right sort of fats is especially important to build a healthy nervous system. Researchers have shown that a diet with a more balanced ratio of Omega-6 to Omega-3 fats (less than 4:1) has profoundly beneficial effects on brain function.

These effects included

- Beneficial effects on brain development in the young

- Improving learning performance and memory

- Reduced cognitive decline with aging

- Reduction in depression

- Improved sleep quality

It’s probably too much to ask any of us to precisely measure the ratio of fatty acids in our diet but it’s very easy for us all to ensure we’re getting more Omega-3 and less Omega-6. Good sources of omega-3 include oily fish, flaxseed oil, and walnuts. It’s also practical and relatively inexpensive to take an Omega-3 supplement every day. Sources of Omega-6 fatty acids which should be minimised include corn, peanut, safflower, palm and soy oils.

A healthy diet is the foundation of a healthy life and the research seems pretty convincing that the right balance of fatty acids is a vital part of getting it all right.