Is Depression a Dietary Problem?

There are two types of essential fatty acids—omega-3s (linolenic acids) and omega-6s (linoleic acids). Both are necessary for health. Omega-6 fatty acids are found in many vegetable oils, including soybean, safflower, corn, sunflower, flax, and walnut oils. Omega-3 fatty acids occur in flaxseeds, hemp, borage, pumpkinseeds, walnuts, and several cold-water fish. The modern diet has an estimated 14:1 ratio of omega-6 to omega-3 fatty acids, compared to a 6:1 ratio consumed by people on a traditional, pre-industrial diet.

British researchers suspect that a lack of omega-3s may be responsible for some cases of depression. They examined the fatty acid composition of red blood cell membranes in both depressed patients and non-depressed controls. The depressed group had significantly fewer omega-3s, particularly docosahexaenoic acid (DHA), than the control group.

The lower level of omega-3s found in the cells of depressed patients may be due to greater oxidative damage of cell membranes, indicating that these people have inadequate antioxidant defenses. Another study found that patients suffering from more severe depression had lower levels of fatty acids and lower dietary intakes of omega-3s than those with milder cases of depression.

Researchers suggest that supplementation with omega-3s might be of therapeutic value for those suffering depression.  Based on information in: Journal of Affective Disorders, 1998, Vol. 48 p. 149