THUNAIOmega-3 fatty acids are found primarily in fish oil and certain marine algae. Because depression appears less common in nations where people eat large amounts of fish, scientists have investigated whether fish oils may prevent and/or treat depression and other mood disorders.
Two omega-3 fatty acids — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — are thought to have the most potential to benefit people with mood disorders.
How might omega-3s improve depression?
Different mechanisms of action have been proposed.
Omega-3s can easily travel through to the brain and interact with mood-related molecules (neurotransmitters - see forthcoming article) inside the brain.
They also have anti-inflammatory actions that may help relieve depression. Inflammation is believed to play a significant role in mood disorders.
More than 30 clinical trials have tested different omega-3 preparations in people with depression. Most studies have used omega-3s as add-on therapy for people who are taking prescription antidepressants with no effect.
Meta-analyses (research that combines and analyzes results of multiple studies) generally suggest that the omega-3s are effective, but the findings are not unanimous because of variability between doses. The most effective preparations appear to have at least 60% EPA relative to DHA.
While DHA is thought to be less effective as an antidepressant, it may have protective effects against suicide. Recent work at Massachusetts General Hospital and Emory University suggests that depressed individuals who are overweight and have elevated inflammatory activity may be particularly good candidates for EPA treatment.
Children and adolescents with depression may also benefit from omega-3 supplementation. At Harvard, there is a large study underway examining whether omega-3 supplementation (alone or in combination with vitamin D) can prevent depression in healthy older adults.
Omega-3s for other mental health conditions:
Omega-3s have been studied in various mood disorders, such as postpartum depression, with some promising results. In bipolar disorder (manic depression), the omega-3s may be most effective for the depressed phase rather than the manic phase of the illness. The omega-3s have also been proposed to alleviate or prevent other psychiatric conditions including schizophrenia, borderline personality disorder, obsessive compulsive disorder, and attention deficit disorder. However, more study is required to confirm these.
Think of Omega 3 as a sensible additional tool in your Recovery Tool Kit. For Vegetarians, flaxseed oil, spinach, mustard seeds, and cauliflower are good substitutes.