Associations between increases in plasma n-3 polyunsaturated fatty acids following supplementation and decreases in anger and anxiety in substance abusers

Mounting evidence indicates that low levels of n-3 polyunsaturated fatty acids (PUFAs) play a role in the pathophysiology of a large number of psychiatric disorders. In light of the suboptimal n-3 PUFAs intake due to poor dietary habits among substance abusers and the strong associations between aggression, anxiety and substance use disorders we examined if insurance of adequate intakes of n-3 PUFAs with supplementation would decrease their anger and anxiety scores. Substance abusers ( n = 22) were assigned to either 3 g of n-3 PUFAs, mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or soybean oil in identically looking capsules. The trial was double-blind, randomized and lasted 3 months. Anger and anxiety scales were administered at baseline and once a month thereafter. Blood samples were collected at baseline and at the end of the trial. Patients' dietary intakes of n-3 PUFAs fell below recommended levels. Assignment to n-3 PUFA treatment was accompanied by significant decreases in anger and anxiety scores compared to placebo assignment. These changes were associated with increases in plasma levels of both EPA and DHA but an increase in EPA was more robustly correlated with low end-of-trial anxiety scores and an increase in DHA was more robustly correlated with low end-of-trial anger scores. These pilot data indicate that ensuring adequate n-3 PUFA intake via supplementation benefits substance abusers by reducing their anger and anxiety levels. The strong correlations between an increase in plasma EPA and lower anxiety scores and between an increase in plasma DHA and lower anger scores suggests a need for the further exploration of the differential responses to these two n-3 PUFAs in different psychiatric conditions.