Candy as a kid leads to violence as an adult, according to a recent British Journal of Psychiatry study:
Children who ate confectionery daily at age 10 years were significantly more likely to have been convicted for violence at age 34 years, a relationship that was robust when controlling for ecological and individual factors.
A popular-press article attributes the problem to parents not teaching their children to delay gratification:
Lead researcher Dr Simon Moore, School of Dentistry, said: “Our favoured explanation is that giving children sweets and chocolate regularly may stop them learning how to wait to obtain something they want. Not being able to defer gratification may push them towards more impulsive behaviour, which is strongly associated with delinquency.”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.”
Dave of Evidence Based Parenting finds that explanation unsatisfying:
My guess is that there’s a large genetic component: the kids who are naturally bad at resisting temptation eat a lot of candy at 10 and are more prone to violence at 34.You could test that by looking at kids who’ve taken the marshmallow test to measure their willpower at 4, measure candy consumption at 10, and violence as an adult. My prediction would be that all those would be correlated, and the candy consumption would vanish as a predictive variable once you introduce the earlier measure.
Also, note how odd it is that the researchers suggest that the candy is indicative of impulsiveness and lack of ability to delay gratification, and then still suggest that intervening in diets may help. Surely if the problem is willpower, then simply restricting access to candy bars in an effort to improve a kid’s diet isn’t going to help.
It gets worse, because there’s at least one study that finds that restricting candy actually harms willpower.