Influence of supplementary vitamins, minerals and essential fatty acids on the antisocial behaviour of young adult prisoners. Randomised, placebo-controlled trial.

BACKGROUND There is evidence that offenders consume diets lacking in essential nutrients and this could adversely affect their behaviour. AIMS To test empirically if physiologically adequate intakes of vitamins, minerals and essential fatty acids cause a reduction in antisocial behaviour. METHOD Experimental, double-blind, placebo-controlled, randomised trial of nutritional supplements on 231 young adult prisoners, comparing disciplinary offences before and during supplementation. RESULTS Compared with placebos, those receiving the active capsules committed an average of 26.3% (95% CI 8.3-44.33%) fewer offences (P=0.03, two-tailed). Compared to baseline, the effect on those taking active supplements for a minimum of 2 weeks (n=172) was an average 35.1% (95% CI 16.3-53.9%) reduction of offences (P<0.001, two-tailed), whereas placebos remained within standard error. CONCLUSIONS Antisocial behaviour in prisons, including violence, are reduced by vitamins, minerals and essential fatty acids with similar implications for those eating poor diets in the community.