The results of a major review of published research that examined the relationship between depression and the level of omega-3 fatty acids in the diet, suggest that omega-3 fatty acids have antidepressant effects. However, the researchers point out that the quality of the studies means it's still too soon to say definitively that omega-3s can treat depression or bipolar disorder.
More fish, less depressionLin and Su reviewed 10 clinical trials, lasting four weeks or longer, which used two omega-3 PUFAs - eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) - to treat depression or bipolar disorder.
Fish and fish oil, as well as flax seed oil, are rich sources of omega-3 polyunsaturated fatty acids (PUFAs). Because areas in which there is high omega-3 PUFA consumption have a lower prevalence of depression, much interest has been generated in their use as antidepressants, the researchers note in the Journal of Clinical Psychiatry.
Further research needed
However, because the trials used different methods to analyse the data, the researchers say the findings must be interpreted with caution. There is also evidence for publication bias, they add, meaning studies that didn't find a benefit of omega-3s were less likely to have been published than those with positive results.
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