Depression and other mood disorders are increasingly common, and they are one of the leading causes of disability worldwide. Depression is a complex disorder with many potential underlying reasons for its manifestations, including experiential, lifestyle, genetic, socioeconomic, and biological factors. Some of the biological influences on the development of depression may include neurotransmitter imbalances (serotonin, dopamine, glutamine, and gamma-aminobutyric acid (GABA), hypothalamic-pituitary-adrenal (HPA) axis dysfunction, and chronic inflammation. As such, any potential treatment plan may incorporate a variety of approaches, including diet and lifestyle changes. One avenue under investigation includes adding more omega-3 fatty acids to the diet.

Omega-3 fatty acids support many components of health, which includes promoting a healthy inflammatory response and supporting brain health and cognitive function. The omega-3 fatty acids include the shorter chained alpha-linolenic acid (ALA) and the longer chained eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Through various processes, ALA can be converted into EPA and DHA. EPA also acts as a precursor for anti-inflammatory prostaglandins. Omega-6 fatty acids are also essential, with linoleic acid converting into pro-inflammatory eicosanoids and prostaglandins. A balance between the two supports eicosanoid balance, which has a downstream effect of balancing inflammatory and anti-inflammatory cytokines.

Omega-3 fatty acids may be used in cell membranes. The unsaturated nature of omega-3 fatty acids may impart fluidity to the membrane. This may help support normal neurotransmitter synthesis and transmission, including that of dopamine and serotonin. Studies have found an association between omega-3 fatty acid membrane changes and changes in serotonin and dopamine receptor number and functions. It may also support normal glutamatergic transmission. Omega-3 fatty acids may also promote a normal stress response, including the support of normal HPA axis dysfunction. Thus, omega-3 fatty acids have many potential ways they may support mood.

Studies have assessed the use of omega-3 fatty acids as a potential treatment for depression and other mood disorders. One meta-analysis of studies using EPA to support depression found that supplements containing ≥60% EPA, in doses ranging from 200 mg to 2,200 mg of EPA in excess of DHA led to improved depression scores, whereas those with less than 60% EPA were ineffective. The researchers determined that it was more effective for EPA to be unopposed by DHA to support mood. Likewise, another meta-analysis found potential for EPA to help support depression. In an analysis of 26 studies, with a total of 2,160 participants, 100% EPA and EPA to ≥60% at doses ≤1 g per day led to clinical benefits. Formulations with DHA as the major contributor did not impart similar results.

Incorporating foods rich in omega-3 fatty acids as part of an overall healthy diet may help support a more balanced omega-6 to omega-3 fatty acid ratio and promote a healthy inflammatory response. This may help support overall health, including supporting mood. Research demonstrates potential promise for increasing EPA levels through supplementation to further support mood.

By Kendra Whitmire, MS, CNS