By PT Staff, published on March 1, 1998 - last reviewed on June 13, 2012
Fat but happy may not be just a cliche anymore. So called "goodfats"-especially omega-3 essential fatty acids, found commonly in fish—are known to prevent coronary disease and boost both the immune and nervous systems. But the good news gets better than that: these fats might even improve your brain function and put you in a better mood—and they might do it permanently.
The brain, which is composed of an astonishing 60% fat, needs adequate amounts of these fatty acids for mental health. For instance, the primary building blocks of the brain and the retina is an omega-3 fatty acid called DHA, or docosahexaenoic acid, which is found in red meat, egg yolks, and in oily fish such as sardines and tuna. A growing number of studies point to possible links between low levels of DHA and depression, memory loss, visual disorders, and other various neurological dysfunctions.
For instance, Dr. Ernst Schaefer of the Human Nutrition Center on Aging at Tufts University has found that a low level of DHA is a risk factor for dementia (a category that includes Alzheimer's). DHA seems useful in treating the difficulties that dyslexics often have in processing visual stimuli. Research from the National Institute of Health points to the low levels of omega-3 fatty acids as a factor in the risk of depression. A similar study published in the American Journal of Clinical Nutrition shows a link between the marked increase in depression in North America and the decline in the consumption of DHA during the same period.
Such evidence supports supplementing your diet with DHA to ensure optimal function of the brain and transmission of nerve signals. Although dietary consumption of DHA (from oily fish such as mackerel and herring) would provide sufficient amounts of the fatty acid, supplements are free of the toxins and chemical pollutants reported to be found in such fish oils. Dr. David J. Kyle, senior VP of research and development at Martek, agrees there's plenty of additional evidence to support its usage. "As a rule, clinical trials don't take place on healthy people, but there are studies, like a recent one from Tufts, that show if you have low levels of DHA, you have a 70 percent higher risk factor of dementia in old age." He also points to Japanese studies that demonstrate improvement in short-term memory and night vision of healthy individuals who have been taking DHA supplements.
And how would you know if you're DHA deficient? "Unless you're eating broiled mackerel or herring three times a week, you're probably only getting 50 of the 200 grams of DHA that should be in your daily diet. So in short, if you're an American, you most probably are." And if you're on a low-fat diet, you can count on it.
PHOTO (COLOR): "Omega-3 FATTY acids are not just HEART-healthy, they are brain-HEALTHY too."