Background:
Over the past century, consumption of omega-3 polyunsaturated fatty acids has decreased dramatically in Western diets, while consumption of omega-6 has increased. There is mounting evidence suggesting that deficits in dietary intake of omega-3 are associated with a range of health problems, including mood disorders. This review will outline the epi-demiological and clinical evidence for an association between omega-3 depletion and mood disorders, including unipolar, bipolar and perinatal depression and suicide risk.
Method:
Relevant published studies are reviewed and theories regarding the mechanisms of action are presented.
Results:
Strong correlations between rates of seafood consumption and mood disorders have been observed in several epidemiological studies. Biochemical studies indicate that omega-3 levels are lower in the tissue of people with depressive disorders than matched controls. The results of several randomized controlled trials indicate that omega-3 supplementation may have therapeutic benefit for depression suffers, although not all trials have shown a benefit.
Conclusions:
Deficits in omega-3 fatty acids are associated with increased prevalence of mood disorders and offer a potential rational treatment approach. A similar relationship between omega-3 depletion and coronary artery disease may explain the well-described links between coronary artery disease and depression. Inconsistency in clinical trial results to date may reflect differences in the type and dose of omega-3 supplement chosen, the depression subtype and/or baseline omega-3 levels of the study participants.