International Review of Psychiatry April 2006; Vol. 18; No. 2; pp. 107–118

Joseph R. Hibbeln, Teresa A. Ferguson, Tanya L. Blasbalg:

From the National Institute on Alcohol Abuse and Alcoholism, Bethesda, USA.

Introduction:

Aggression and depression are widespread challenges affecting individuals worldwide, with significant implications for public health. In recent years, researchers have delved into the intricate relationship between nutritional deficiencies, specifically in omega-3 fatty acids, and the exacerbation of aggressive and depressive disorders. This article explores key findings and highlights the importance of omega-3 fatty acids in promoting mental well-being.

Global Impact of Major Depression:

Major depression ranks as the fourth leading cause of disease burden globally, with projections indicating that neuropsychiatric disorders will account for 14% of the global burden of disease by 2020. Recognizing the substantial impact of mental health issues on society, researchers have turned their attention to the role of omega-3 fatty acids in mitigating these challenges.

Omega-3 Fatty Acids and Biological Roles:

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), both crucial omega-3 fatty acids, play essential biological roles in reducing cardiovascular mortality. Deficiencies in these long-chain essential fatty acids during critical periods of neurodevelopment may contribute to a predisposition toward aggressive and depressive behaviors. This is linked to impairments in neuronal migration, connectivity, apoptosis, and dendritic arborization, resulting in irreversible disruptions in the neuronal pathways regulating behavior.

Serotonin and Omega-3 Fatty Acids:

Serotonin, often referred to as the “happiness neurotransmitter,” plays a vital role in regulating mood. Early developmental deficiencies in DHA and EPA may lower serotonin levels, contributing to suboptimal development of neurotransmitter systems. Increasing omega-3 fatty acid intake has the potential to elevate brain serotonin concentrations, thereby influencing emotional regulation.

Heart Rate Variability and Omega-3 Fatty Acids:

Residual developmental deficits linked to omega-3 insufficiency may manifest as dysregulation of sympathetic responses to stress, decreased heart rate variability, and hypertension. Omega-3 fatty acids can enhance heart rate variability, associated with a decreased risk of sudden cardiac death. Reduced serotonergic function, influenced by low EPA and DHA levels, may further contribute to diminished heart rate variability and autonomic nervous system activity.

Impact on Infants and Children:

Omega-3 fatty acids are crucial for optimal brain function during infancy. Deficiencies during critical time periods can lead to neurodevelopmental deficits and predispose individuals to depression or aggressive behaviors. Behavioral problems reported in children with lower omega-3 fatty acid concentrations suggest a potential link between nutrition and mental health.

Omega-3 Fatty Acids and Aggression:

Low omega-3 levels are associated with aggression, and dietary choices high in omega-6 fatty acids increase the risk of hostility and attention deficit hyperactivity disorder. Supplementation with omega-3 fatty acids has shown promise in reducing felony-level violence among prisoners and decreasing aggression in individuals with borderline personality disorder.

Conclusion:

Ensuring optimal intake of omega-3 fatty acids emerges as a promising avenue for preventing and mitigating aggression and depression. The impact of nutrition on mental health is a growing area of research, and the readily available and non-toxic nature of omega-3 fatty acids positions them as a valuable resource in promoting public mental well-being. As we continue to unravel the complexities of psychiatric disorders, addressing nutritional factors like omega-3 fatty acids may prove instrumental in enhancing mental health on a global scale.