Omega-3 fatty acids have long been associated with improved cardiovascular health. More recently, these polyunsaturated fatty acids, including docosahexaenoic acid (DHA), have been identified as essential to mental health as well. Specifically, a new study of military personnel published by the Journal of Clinical Psychiatry concludes that low levels of DHA are associated with an increased suicide risk.

For this retrospective case-control study, blood samples of 800 American military personnel who had committed suicide were compared to samples from 800 age- and gender-matched healthy controls. All individuals were active duty military personnel at the time of the study, between 2002 and 2008. Of the suicide deaths, nearly 96% of the individuals were male and the mean age was 27.3 years (range 17 to 59 years). The authors concluded that all military personnel had low levels of DHA compared to the general population, but each standard deviation of lower DHA was associated with a 14% increased risk of suicide. Those with the lowest levels had a 62% increased risk of suicide.

In 2006, the American Psychiatry Association, recognizing the importance of omega-3 fatty acids in brain function, established guidelines recommending intake of 1 gram per day of omega-3 fatty acids for anyone with a psychiatric disorder; the US Food and Drug Administration notes that intake of up to 3 grams per day is safe. Omega-3 fatty acids are found in cold water oily fish, krill, some seeds and nuts, some red meat, and plenty of dietary supplements and fortified foods.

Omega-3 fatty acids have been evaluated in symptoms of stress, cognitive disorders, anxiety disorders, autism, attention-deficit hyperactivity disorder, personality disorders, schizophrenia, psychosis, bipolar disorder, and major depressive disorder. Overall, the research indicates that omega-3 fatty acids may have a therapeutic benefit in many psychiatric disorders. Omega-3 supplements have shown effectiveness as monotherapy and have also improved traditional therapy when used with other drugs. Of course, there are confounding factors, including genetics, environmental exposures, diet, and smoking habits, that contribute to the risk of mental illness and therapeutic effectiveness.

Fatty acids are critical to psychiatric, neurological, and developmental functioning in the human brain and central nervous system. They possess numerous health benefits and should be considered a key nutrient in the diets of children and adults. The current study points toward improved dietary habits for military personnel, but the findings can likely be extrapolated to more general populations. Omega-3 fatty acids are safe when consumed in food or dietary supplements and pose very little risk of side effects or drug interactions. No study has proven causality between omega-3 fatty acid intake and the development of mental illness, but it is likely a “no-brainer” that omega-3 intake should be considered vital to preventive medicine.

References

Lewis, M., Hibbeln, J., Johnson, J., Lin, Y., Hyun, D., & Loewke, J. (2011). Suicide Deaths of Active-Duty US Military and Omega-3 Fatty-Acid Status The Journal of Clinical Psychiatry DOI: 10.4088/JCP.11m06879

McNamara RK (2011). Long-Chain Omega-3 Fatty Acid Deficiency in Mood Disorders: Rationale for Treatment and Prevention. Current drug discovery technologies PMID: 21838665

Perica MM, & Delas I (2011). Essential fatty acids and psychiatric disorders. Nutrition in clinical practice : official publication of the American Society for Parenteral and Enteral Nutrition, 26 (4), 409-25 PMID: 21775637

Politi P, Rocchetti M, Emanuele E, Rondanelli M, & Barale F (2011). Randomized Placebo-Controlled Trials of Omega-3 Polyunsaturated Fatty Acids in Psychiatric Disorders: a Review of Current Literature. Current drug discovery technologies PMID: 21838664