Getting the right fats for your brain.
Mind, Mood and Memory, November, 2007

Dietary fats are essential for your brain, but they should be healthy fats consumed in the proper amounts. By including optimal amounts of brain health fats and oils in your diet and limiting or avoiding those with negative effects, you can help ensure that your mind has the nutrients needed to work well.

Too much unhealthy fat can harm the brain by clogging blood vessels, impairing communication among cells, negatively influencing mood and discouraging the formation of nerve connections important to learning, concentration and memory. The balance of fats you eat, as well as the type of fats, appears to be important to your brain health.

A recent study suggests that the imbalance of omega-3 and omega-6 fatty acids found in certain fats and oils may be linked to depression. Researchers measured levels of the fatty acids in the bloodstreams of 43 older men ands women who were assessed for symptoms of depression. The scientists found that among subjects diagnosed with major depression, the ratio of omega-6 fatty acid to omega-3 fatty acid was 18 to 1, while the ratio among subjects without depression was only 13 to 1. As the ratio of omega-6 to omega-3 rose, so did depression severity, the researchers reported in the March 30 online edition of the Journal of Psychosomatic Medicine. Subjects with higher Omega 6 levels also potentially harmful inflammation promoting compounds.

“The brain is primarily a fat based organ” says David Mischoulon MD, PhD, Director of Alternative Remedy Studies at Massachusetts General Hospital’s Depression Clinical and Research Program. “Almost 60 per cent of the brain is composed of fat like substances called lipids, which act as cerebral building blocks. They make up essential brain structures, including the myelin sheaths that coat nerve fibers and the membranes, or linings of brain cells.

“Because your brain must have dietary fats to function properly, it matters very much what types of fats you consume and in what proportions.

It’s important to learn about the make-up of fats and oils you need to achieve optimal brain functioning.”

Fat Facts
The mix of fats you consume can effect the formation of cholesterol, a waxy substance that plays an important role in heart disease. High levels of the “bad” LDL form of cholesterol lead to deposits in arteries, called plaque and increase the risk of heart disease, stroke and cognitive problems linked to restrictive blood flow to the brain. “Good” HDL cholesterol is associated with the process of eliminating cholesterol from the body. And a reduction in the likelihood of plaque formation. Generally speaking, fats that worsen blood cholesterol levels ate considered unhealthy and those that improve cholesterol levels are considered healthy.

The chemical structure of fatty acids contained in fats and oils are also important determinants of brain health.

Brain Healthy Fats
Unsaturated fats are derived from plant sources such as nuts, seeds and vegetable oils and from fish. Consuming them may help lower levels of LDL and increase levels of HDL. These fats are divided into two major groups:
• Monounsaturated fats: These healthy fats are found in high concentration in avocados, peanuts, almonds, sesame seeds, cashews, hazel nuts, olive oil and canola oil.
• Polyunsaturated fats: Rich concentrations of these fats may be found in vegetable oils such as sunflower oil, corn oil, safflower oil and soybean oil. They are also found in seafood. Two types of polyunsaturated fat – omega 6 and omega 3 fatty acids – are important to brain function but Americans tend to eat too much of the former and too little of the latter. A ratio of 3 to 1 would be ideal.

Omega 3 is an essential fatty acid found in high concentration in flaxseed and hemp oil and in fatty cold water fish such as sardines, mackerel, salmon, halibut and tune. Smaller quantities can also be found in green, leafy vegetables and walnuts. Two types of Omega 3 acids are eicosapentaenoic (EPA) and docosahexaenoic acid (DHA). Research suggests omega 3 reduces blood clotting and helps improve communication among brain cells. Insufficiency of this important fatty acid in the diet has been linked to increased risk for ischemic stroke, cardiovascular risk, hypertension, depression and Alzheimer’s disease.

Omega 6, a fatty acid found in processed foods and in vegetable oils derived from corn, safflower, cottonseeds and sunflower seeds convert to beneficial arachidonic acid (AA) in the body. Up to half of the fatty acids in the brain’s gray matter are made up of DHA and AA. However, too much omega 6 can cause imbalance that has negative consequences for brain health.

Your Health and Mine