Background:

Scientists at the National Institute on Alcohol Abuse and Alcoholism (NIAAA) led by CAPT Joseph R. Hibbeln, M.D., teamed with researchers at the Uniformed Services University of the Health Sciences (USUHS) in Bethesda, Md., to analyze a sample of suicide deaths among U.S. military personnel on active duty between 2002 and 2008. The researchers compared levels of omega-3 fatty acids of 800 individuals who committed suicide with those of 800 randomly selected controls--service members who were matched with the suicide cases by age, sex, and rank.  They found that all the service members had low omega-3 levels, and that suicide risk was greatest among individuals with the lowest levels of docosahexaenoic acid (DHA), the major omega-3 fatty acid concentrated in the brain.  The new study is reported online in the Journal of Clinical Psychiatry, and summarized in a USUHS press release.

Statement of CAPT Joseph R. Hibbeln, M.D., acting chief, Section of Nutritional Neurosciences, NIAAA Laboratory of Membrane Biochemistry and Biophysics:

The findings add to an extensive body of research that points to a fundamental role for DHA and other omega-3 fatty acids in protecting against mental health problems and suicide risks.  For example, a previous placebo-controlled trial demonstrated that 2 grams of omega-3 fatty acids per day reduced suicidal thinking by 45 percent as well as depression and anxiety scores among individuals with recurrent self-harm.  In a prior study we found that low blood levels of DHA correlated with hyperactivity of brain regions in a pattern that closely resembles the pathology of major depression and suicide risk.  While omega-3 fatty acids are generally recommended by the American Psychiatric Association as an adjunctive therapy for mood disorders, more research is needed to establish a definitive role for their use in the stand alone treatment of depression.

The identification of low DHA status as a significant risk factor for suicide deaths should complement ongoing efforts in the U.S. military to study modifiable risk and protective factors related to mental health and suicide among U.S. military personnel.  The U.S. military invests a great deal of funds and effort to ensure that its troops receive optimal nutrition, especially in combat and deployment situations.  This study presents new information on the potential usefulness of omega-3 fats in reducing risk for suicide and optimizing mental health, which can be taken into account when designing U.S. military diets.