Omega-3 fatty acids and mental health

Abstract

Nutrition plays a key role in brain development, mental health, and psychiatric disorders. The role of omega-3 polyunsaturated fatty acids in physical health is well established, and their role in mental health is becoming increasingly evident. Omega-3 fatty acids are involved in a wide range of physiological functions that are related to neurogenesis, neurotransmission, and neuroinflammation; therefore, they play fundamental roles in the development, functioning, and aging of the brain. In humans, dietary deficiencies of omega-3 fatty acids are associated with an increased risk of developing various psychiatric disorders, including depression, bipolar disorder, schizophrenia, dementia, attention-deficit/hyperactivity disorder, and autism. In particular, eicosapentaenoic and docosahexaenoic acid have been linked to the maintenance of mental health, and their deficits have been implicated in the pathophysiology of mental disorders. This may be mediated by the modulation of inflammatory processes and their direct effects on neuronal membrane fluidity and receptor function. However, randomized clinical trials that have investigated the therapeutic effects of omega-3 fatty acids have yielded inconclusive results, thereby limiting the use of these nutrients in psychiatric practice. High-quality clinical trials should be conducted to examine the efficacy of omega-3 fatty acids in preventing and treating mental disorders. The undesirable side effects of omega-3 fatty acid supplementation should also be considered. These effects may become apparent after many years of administration, and therefore, they may not be detected in most cases.