SHEFFIELD, UNITED KINGDOM. The composition of cell membranes has a profound effect on membrane-related proteins such as enzymes and receptors and there is considerable evidence that cell membrane structure is a significant factor in depression. This structure in turn is highly dependent on the presence of certain essential fatty acids, notably docosahexaenoic acid (DHA).
Researchers at the University of Sheffield and the Efamol Research Institute in Nova Scotia now report that they have found a highly significant association between severity of depression and the levels of omega-3 fatty acids in both the diet and the red blood cell membranes.
Their study involved 10 patients with major depression and 14 healthy control subjects with no history of psychiatric disorder (average age of participants was 39 years). All participants had blood samples taken and analyzed for essential fatty acid (EFA) content and also completed a questionnaire to determine their dietary intake of EFAs over the 7 days prior to enrollment.
The severity of depression was found to be inversely proportional with the red blood cell level and dietary intake of omega-3s. The correlation between a low level of alpha-linolenic acid in blood cells and depression and between low blood cell levels of DHA and depression were particularly strong. No correlation was found between red blood cell levels of omega-6s and depression. However, there was a slight positive correlation between dietary intake of omega-6s and severity of depression when both patients and controls were considered in one group. The researchers conclude that low levels of omega-3s in cell membranes are associated with depression. They speculate that supplementation with omega-3s may be useful in alleviating depression.
Edwards, Rhian, et al. Omega-3 polyunsaturated fatty acid levels in the diet and in red blood cell membranes of depressed patients. Journal of Affective Disorders, Vol. 48, 1998, pp. 149-55