07 Nov Do Omega-3 Fatty Acids Effect Major Depressive Disorder?
MedicalResearch.com Interview with:
Katherine Appleton PhD
Associate Professor In Psychology
Medical Research: What is the background for this study?
Dr. Appleton: Major depressive disorder (MDD) is characterized by depressed mood and/or markedly decreased pleasure or interest in all activities. It has negative impacts on the individual and on society, often over the long term. One possible treatment for MDD are n-3 polyunsaturated fatty acids (n-3PUFAs), also known as omega-3 oils, naturally found in fatty fish, some other seafood and some nuts and seeds. Various lines of evidence suggests that n-3PUFAs may impact on depressive symptoms, but a lot of studies have different findings, making it difficult to draw conclusions.
Medical Research: What are the main findings?
Dr. Appleton: We searched scientific databases for all randomized controlled trials in adults with a diagnosis of Major depressive disorder, where individuals received either n-3PUFAs or an alternative, that were carried out up to May 2015.
We found 26 relevant studies: 25 studies involving 1438 people compared the impact of n-3PUFAs with that of placebo, and one study involving 40 people compared the impact of n-3PUFAs with that of antidepressants.
In analyses, we found a small-to-modest positive effect of n-3PUFAs compared to placebo, but the size of this effect is unlikely to be meaningful to people with depression, and we considered the evidence to be of low quality, with many differences between studies. There was also insufficient high quality evidence to determine the effects of n-3PUFAs on negative side effects or numbers failing to complete trials.
We conclude that at present, we do not have enough high quality evidence to determine the effects of n-3PUFAs as a treatment for Major depressive disorder.
Medical Research: What should clinicians and patients take away from your report?
Dr. Appleton: At present, we do not have enough high quality evidence to determine the effects of n-3PUFAs as a treatment for Major depressive disorder.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Appleton: We need more evidence, particularly to explain the differences between study findings, e.g. by looking at individuals who may and may not benefit from n-3PUFAs. Future studies should also compare n-3PUFAs with usual antidepressant treatment, and investigate the way these treatments may work.
Appleton KM, Sallis HM, Perry R, Ness AR, Churchill R. Omega-3 fatty acids for depression in adults. Cochrane Database of Systematic Reviews 2014, Issue 5 . Art. No.: CD004692.
Katherine Appleton PhD (2015). Do Omega-3 Fatty Acids Effect Major Depressive Disorder?