The 1970 British Cohort Study involving17,500 participants, designed to examine the long-term effects of childhood diet on adult violence, found that 10-year-olds who ate confectionary daily were significantly more likely to have been convicted for violence at age 34 years.
The researchers led by Dr Simon Moore found that 69 per cent of the participants who were violent at the age of 34 had eaten sweets and chocolate nearly every day during childhood, compared to 42% who were non-violent.
"It's not that the sweets themselves are bad, it's more about interpreting how kids make decisions," said Simon Moore of the University of Cardiff, one of the paper's authors.
Moore said parents who consistently bribe their children into good behavior with candies and chocolates could be doing harm. That might prevent kids from learning how to defer gratification, leading to impulsive behavior and violence.
Even after Moore and colleagues controlled for other variables like different parenting skills and varying social and economic backgrounds, they found a significant link between childhood consumption of sweets and violent behavior in adulthood.
Previous studies have found better nutrition leads to better behavior, in both children and adults.
The researchers concluded: "This association between confectionary consumption and violence needs further attention. Targeting resources at improving children's diet may improve health and reduce aggression."
(See the following article on Omega-3, Vitamins, Minerals and Aggressive Behaviour)
Moore SC, Carter LM and van Goozen SHM. Confectionary consumption in childhood and adult violence. British Journal of Psychiatry, 195: 366-367