Keep calm and try omega-3. The fatty acids, available as dietary supplements via fish oil capsules and thought to help with mental and physical well-being, could also cut down on aggression, according to a new study.

These findings haven't come out of nowhere: omega-3 has previously been linked to preventing schizophrenia, while aggression and antisocial behavior are thought in part to stem from a lack of nutrition. What we eat can influence our brain's chemistry.

Researchers from the University of Pennsylvania built on earlier, smaller studies of omega-3 supplementation effects on aggression. Their meta-analysis looked at 29 randomized controlled trials across 3,918 participants in total.

Across all the trials, a modest but noticeable short-term effect was found, translating to up to a 28 percent reduction in aggression across multiple different variables (including age, gender, medical diagnosis, and length and dosage of treatment).

"I think the time has come to implement omega-3 supplementation to reduce aggression, irrespective of whether the setting is the community, the clinic, or the criminal justice system," says neurocriminologist Adrian Raine.

The trials included in the study, carried out between 1996 and 2024, ran for an average of 16 weeks. They covered a variety of demographics, from children aged 16 and under to older people aged between 50 and 60.

What's more, the reductions in aggression included both reactive aggression (in response to provocation) and proactive aggression (behavior planned in advance). Before this study, it wasn't clear if omega-3 could help with these different types of aggression.

While larger studies across longer periods of time are going to be needed to further establish this relationship, it adds to our understanding of how fish oil pills and the omega-3 in them might be beneficial for the brain.

"At the very least, parents seeking treatment for an aggressive child should know that in addition to any other treatment that their child receives, an extra portion or two of fish each week could also help," says Raine.

The researchers think something in the way that omega-3 reduces inflammation and keeps vital brain processes ticking over might be helping regulate aggression. There are still a lot of unanswered questions, but the team suggests there's enough evidence to look into this further.

Add in the studies that show that medications derived from fish oil can help reduce the risk of fatal heart attacks, strokes, and other heart health problems, and there seems to be plenty of upside to adding some omega-3 to your diet.

"Omega-3 is not a magic bullet that is going to completely solve the problem of violence in society," says Raine.

"But can it help? Based on these findings, we firmly believe it can, and we should start to act on the new knowledge we have."

The research has been published in Aggression and Violent Behavior.