Dietary Intake of N-3 and N-6 Fatty Acids and the Risk of Clinical Depression in Women: a 10-y prospective follow-up study

I love a Walter Willett study. But this one is bittersweet for me. A victory for omega-3s. Another strike against excess omega-6s. But no noted benefits from fish, one of my top brain foods?! That is hard to digest.

Authors M. Lucas, F. Mirzaei, E.J. O’Reilly, A. Pan, W.C. Willett, I. Kawachi, K. Koenen, A. Ascherio
Institution Harvard School of Public Health
Publication Name The American Journal of Clinical Nutrition
Publication Date June 2011

Background: The associations between different sources of dietary n-3 (omega-3) and n-6 (omega-6) fatty acids and the risk of depression have not been prospectively studied.
Objective: The objective was to examine the relation between different n-3 and n-6 types with clinical depression incidence.
Design: We prospectively studied 54,632 US women from the Nurses’ Health Study who were 50-77 y of age and free from depressive symptoms at baseline. Information on diet was obtained from validated food-frequency questionnaires. Clinical depression was defined as reporting both physician-diagnosed depression and regular antidepressant medication use.
Results: During 10 y of follow-up (1996-2006), 2823 incident cases of depression were documented. Intake of long-chain n-3 fatty acids from fish was not associated with depression risk [relative risk (RR) for 0.3-g/d increment: 0.99; 95% CI: 0.88, 1.10], whereas α-linolenic acid (ALA) intake was inversely associated with depression risk (multivariate RR for 0.5-g/d increment: 0.82; 95% CI: 0.71, 0.94). The inverse association between ALA and depression was stronger in women with low linoleic acid (LA) intake (P for interaction = 0.02): a 0.5-g/d increment in ALA was inversely associated with depression in the first, second, and third LA quintiles [RR (95% CI): 0.57 (0.37, 0.87), 0.62 (0.41, 0.93), and 0.68 (0.47, 0.96), respectively] but not in the fourth and fifth quintiles.
Conclusions: The results of this large longitudinal study do not support a protective effect of long-chain n-3 from fish on depression risk. Although these data support the hypothesis that higher ALA and lower LA intakes reduce depression risk, this relation warrants further investigation.

Drew Ramsey, MD

Drew Ramsey, M.D. is a psychiatrist, author, and farmer. He is a clear voice in the mental health conversation and one of psychiatry’s leading proponents of using nutritional interventions. He is an assistant clinical professor of psychiatry at Columbia University College of Physicians and Surgeons.

Other Articles You May Like

Submit a Comment