Public health researchers are entering the New South Wales prison system to find out whether eating more fish makes you less violent.
University of Wollongong researchers want to know if the good fats - like Omega 3 - might reduce criminal behaviour.
Associate Professor Barbara Meyer from the university's School of Health Sciences says small overseas studies suggest higher levels of Omega 3 do lead to less offending.
"One in the UK by Dr Bernard Gesch, who is involved the Australian research project, found with supplementing the young offenders there was a 35 per cent reduction in offensive behaviour," she said.
The pilot randomised control trial of fish oil supplementation and multivitamins is being conducted at the South Coast Correctional Centre in Nowra.
Corrective Services Assistant Commissioner of Strategic Policy and Planning Luke Grant says the prison service is very interested in the emerging link between biology and behaviour.
"There has been a bit of a truism in prison that a well fed prison is a happy prison," he said.
"So people have often noted a connection... but not necessarily to the extent that it has been established in any scientific way."
Associate Professor Meyer says Omega 3s are a vital nutrient incorporated into brain tissue, and studies show that chemical signals in the brain are related to behaviour.
"What we are trying to determine now is if we increase the amount of Omega 3 - we are assuming it increases in the brain - if it has an effect on reducing aggression," she said.
The study will include psychological questionnaires on aggression and inattention, and is the first to use blood tests.
"We are doing blood testing to check compliance, as well also to check fatty acid metabolism, and find out mechanically what is going on, whether they eat fish or are given supplements," Professor Meyer said.
Assistant Commissioner Grant says he believes it is the first study of its kind.
"If you look at the history of corrections going back over several 100 years, corrections really are a great experiment," he said.
"There has been an enormous series of failed experiments where people haven't bothered to determine whether or not correctional policies or practices had an effect.
"We don't assume that is going to revolutionise and change the outcomes for every prisoner; what we are interested in is as many different ways that we can impact on community safety, as they are available."
Researchers hope that after analysis of the pilot study, the research could be extended to other prisons and in time move to national trials.