The case for omega-3 supplementation to lower aggression

People who eat fish regularly or take fish oil supplements are getting omega-3 fatty acids, which play a key role in brain function. Research over the years has shown that the brain is the basis for aggressive and violent behavior, and that nutritional deficiencies are a risk factor for behavioral disorders.

Adrian Raine, a neurocriminologist at the University of Pennsylvania, has been studying for years whether omega-3 supplements can reduce aggressive behavior, publishing five randomized controlled trials conducted in different countries. Raine found a large effect, but he wanted to know whether the findings extended beyond his own lab.

Now, Lane has conducted a meta-analysis of 29 randomized controlled trials and found further evidence of the effectiveness of omega-3 supplements. The meta-analysis showed modest short-term benefits across age, sex, diagnosis, length of treatment and dose, with Lane estimating that the intervention reduces aggression by 30%.

Laing is lead author of the new paper. Published In the journal Aggressive and violent behaviorThe research was conducted in collaboration with Leah Brodrick of the Perelman School of Medicine.

“Whether in the community, in the clinic or in the criminal justice system, I think it’s time to start taking omega-3 supplements to reduce aggression,” says Lane. “Omega-3 is not a magic pill that will completely solve society’s violence problems, but can it help? Based on these findings, we believe it can, and we need to start acting on the new knowledge we have.”

Omega-3s are also effective in treating heart disease and high blood pressure, and they’re cheap and safe to use, he notes. “At the very least, parents seeking treatment for their aggressive children should know that eating one or two extra servings of fish each week can be beneficial, in addition to any other treatment their child receives,” says Lane.

This meta-analysis showed that omega-3s reduced both reactive aggression, which is behavior that occurs in response to provocation, and proactive aggression, which is planned behavior.

The study included 35 independent samples from 29 studies conducted in 19 independent laboratories with 3,918 participants between 1996 and 2024. Statistically significant effects were found when effect sizes were averaged by study, independent sample, or laboratory.

Of the 19 laboratories, only one followed up participants after they had stopped taking the supplements, so the analysis focused on the change in aggression in the experimental and control groups from the start to the end of treatment (an average of 16 weeks). “While it is valuable to know whether omega-3 reduces aggression in the short term, the next step is to assess whether omega-3 can reduce aggression in the long term,” the paper states.

The paper notes several possible directions for future research, including whether brain imaging tests can show that omega-3 supplements enhance frontal lobe function, whether genetic variants influence the outcome of omega-3 treatment, and whether self-reported measures of aggression provide stronger evidence of validity than observer reports.

“At the very least, we argue that omega-3 supplementation should be considered as an adjunct to other interventions, whether psychological (e.g., CBT) or pharmacological (e.g., risperidone), and that caregivers should be informed about the potential benefits of omega-3 supplementation,” the authors write.

They conclude that “we believe the time has come to both validate omega-3 supplements in practice and to continue to scientifically investigate their long-term efficacy.”