Malnutrition at Age 3 Years and Externalizing Behavior Problems at Ages 8, 11, and 17 Years

TLDR

Poor nutrition is believed to increase the risk of externalizing behavior problems, yet no prospective longitudinal studies have examined this hypothesis. This study evaluated whether early malnutrition at age 3 predicts antisocial behavior at ages 8, 11, and 17, whether these links are independent of psychosocial adversity, and whether IQ mediates the relationship. Using a birth cohort of 1,795 children, the study assessed malnutrition signs at age 3, cognitive performance at ages 3 and 11, and antisocial, aggressive, and hyperactive behaviors at ages 8, 11, and 17. Children with malnutrition signs at age 3 were more aggressive or hyperactive at 8, had greater externalizing problems at 11, and exhibited more conduct disorder and motor activity at 17; these associations were independent of psychosocial adversity, displayed a dose‑response pattern, were mediated by low IQ, and suggest that reducing early malnutrition could lower later antisocial and aggressive behavior.

Abstract

OBJECTIVE: Poor nutrition is thought to predispose to externalizing behavior problems, but to date there appear to have been no prospective longitudinal studies testing this hypothesis. This study assessed whether 1) poor nutrition at age 3 years predisposes to antisocial behavior at ages 8, 11, and 17 years, 2) such relationships are independent of psychosocial adversity, and 3) IQ mediates the relationship between nutrition and externalizing behavior problems. METHOD: The participants were drawn from a birth cohort (N=1,795) in whom signs of malnutrition were assessed at age 3 years, cognitive measures were assessed at ages 3 and 11 years, and antisocial, aggressive, and hyperactive behavior was assessed at ages 8, 11, and 17 years. RESULTS: In relation to comparison subjects (N=1,206), the children with malnutrition signs at age 3 years (N=353) were more aggressive or hyperactive at age 8 years, had more externalizing problems at age 11, and had greater conduct disorder and excessive motor activity at age 17. The results were independent of psychosocial adversity and were not moderated by gender. There was a dose-response relationship between degree of malnutrition and degree of externalizing behavior at ages 8 and 17. Low IQ mediated the link between malnutrition and externalizing behavior at ages 8 and 11. CONCLUSIONS: These results indicate that malnutrition predisposes to neurocognitive deficits, which in turn predispose to persistent externalizing behavior problems throughout childhood and adolescence. The findings suggest that reducing early malnutrition may help reduce later antisocial and aggressive behavior.