It has often been suggested that there may be a direct link between poor diet and antisocial and hyperactive behaviour but such a hypothesis has been difficult to prove. A recent report, published in the
American Journal of Psychiatry Vol. 161 (11), 2004, seems to support the theory.
The research looked at a group of children from a range of ethnic backgrounds living in Mauritius. The 1795 children were assessed for signs of malnutrition at age 3 and followed until they reached the age of 17. Cognitive measures were assessed at ages three and eleven years, and antisocial, aggressive, and hyperactive behaviour was assessed at ages eight, eleven and seventeen years. The signs of malnutrition looked at were zinc, iron, vitamin B2 and protein. Three hundred and fifty three children were found to be malnourished at age 3 and at age 8 these children had a greater incidence of hyperactivity and aggressiveness. They continued to have problems at age 11 and at age 17 these children had greater conduct disorder and excessive motor activity. Based on the results of the cognitive function tests, the authors hypothesised that early malnutrition negatively affected brain growth and development, and this predisposed the child to antisocial and violent behaviour in later life. Interestingly no differences were found amongst children from different ethnic backgrounds or between the sexes.
The results suggest that the provision of an adequate diet during early development can help prevent antisocial behaviour in later life and these findings have particular relevance for the UK where iron deficiency is one of the most common deficiencies, and in the US where 7% of toddlers are known to be deficient in iron.
