Increasing evidence for omega 3 fatty acid use in depression

Long chain omega 3 fatty acids, those found in oily fish such as salmon, mackerel, trout and sardines, for the treatment and prevention of depression is a topic I have covered quite frequently, and one that I am incredibly passionate about.  The evidence for the use of these fats in the treatment of depression seems to be constantly building.  Recently (1) a study has concluded that supplementation with the long chain omega 3 fatty acids, EPA and DHA (eicosapentaenoic acid and docosahexaenoic acid), is effective in the treatment of depressive symptoms and quality of life of depressed elderly female individuals.

The study scientists (1) wanted to investigate whether a supplement containing long-chain omega-3 fatty acids would improve depressive symptoms and health-related quality of life in depressed elderly female patients (aged 66-95 years old).  The study was a relatively short and small eight week trial which was well designed (it was a randomized, double-blind, placebo-controlled trial).  The intervention group received 2.5g of long chain fatty acids daily, 1.67g of EPA and 0.83g DHA.  Before and after the 8 week supplementation period the researchers assessed depression and quality of life scores in all the participants (the group receiving the supplement and those receiving the placebo) using specific medical scales, they also assessed the changes in fatty acid levels in the individuals’ blood. 

After 8 weeks (1) the scores for depression were significantly lower in the group not receiving the omega 3 fatty acids when compared to the group receiving supplements i.e. the group NOT receiving fatty acids were significantly more depressed than the group taking the supplements.  Specific physical and mental components of the quality of life index scores were significantly increased in the group taking the omega 3 fatty acid supplements.  As expected, those women taking the omega 3 supplement had a significant increase of EPA and DHA in their red blood cell membranes when compared to the group not receiving the supplement.

The study has added to the existing evidence for the importance of omega 3 fatty acids and brain function.  Unfortunately these long chain fatty acids are still not being widely used by the medical community for the treatment of depression, despite the volumes of accumulating evidence for their use. In this particular study it was exciting that the supplements had quite a quick effect, since the trial only lasted 8 weeks.

As you can see from my other posts on the health benefits of long chain omega 3 fatty acids, these fats are not only important for the brain.  They have been implicated in heart health and the health of the immune system as well as having many other documented health benefits.  Eating oily fish at least twice per week will provide the body with a substantial amount of these fats, however in the UK many individuals are not reaching these sorts of levels of intake.  On average, adults in the UK are eating 1/3 of a portion of oily fish per week, with 70% of adults eating no oily fish at all (2).   If you do not regularly eat oily fish you might want to discuss the option of taking a daily fish oil supplement with your doctor.

(1)Rondanelli M et al.  2010.  Effect of omega-3 fatty acids supplementation on depressive symptoms and on health-related quality of life in the treatment of elderly women with depression: a double-blind, placebo-controlled, randomized clinical trial. J Am Coll Nutr.  29(1):55-64.

(2) British Nutrition Foundation.

Written by Ani Kowal