Omega-3 fatty acids have antidepressant properties, study finds

MIAMI — The American College of Neuropsychopharmacology on Wednesday presented a new analysis of the effects of omega-3 essential fatty acids as potential treatment options for depression.

Two critical omega-3 essential fatty acids available from certain food or nutritional supplements but not manufactured by the body — eicosapentenoic acid and docosahexaenoic — play a role in optimal brain functioning and have antidepressant benefits that have not been fully recognized, the professional society stated during its annual meeting in Miami.

In a meta-analysis of 15 randomized, double-blind, placebo-controlled studies, researchers from the University of Illinois at Chicago, led by John Davis, research professor at the University of Illinois at Chicago and ACNP member, found that patients taking omega-3 with either EPA or a combination of EPA and DHA experienced clear antidepressant benefits. However, across studies, patients taking the pure DHA form of omega-3 saw no antidepressant effect.

"Our analysis clarifies the precise type of omega-3 fatty acid that is effective for people with depression and explains why previous findings have been contradictory," Davis said. "The EPA predominant formulation is necessary for the therapeutic action to occur. The DHA predominant formulation does not have antidepressant efficacy."

While scientists noted that omega-3 produces beneficial effects in patients with depression, EPA does not improve mood in people who are not depressed. In several studies, people without depression experienced no difference in mood as a result of omega-3 consumption. In another study, Davis and his team found that women with inadequate omega-3 intake were more likely to experience depression during and after pregnancy than women with adequate omega-3 in their diets.

"The findings are unambiguous," Davis noted. "Omega-3 fatty acids have antidepressant properties, and this effect is ready to be tested in a large study to establish the dose range and to pave the way for [Food and Drug Administration] approval. In the meantime, omega-3 fatty acids containing EPA could be useful to augment effects of antidepressant medications. However, scientists caution that patients should always talk with their mental health professional before taking omega-3 fatty acids to alleviate symptoms of depression."