A survey of more than 33,000 Italian high school students reveals that both underweight and overweight teens consume 20 to 40% more illegal drugs than their normal-weight peers. Further analysis showed that the relationship between these two factors was largely mediated by psychosocial factors such as self-esteem, parents' educational level, and friendships.

Based on these results, the authors conclude that abnormal weight and substance abuse are not directly related in a cause-effect relationship, but instead are likely both due to common underlying social factors and dissatisfaction.

"Eating disorders have largely increased during the last decades, and obesity is a major public-health problem, especially since the phenomenon is spreading among children. Thus we believe that the results are important to better define targeted interventions," says Dr. Sabrina Moinaro.

The work, led by Sabrina Molinaro and Francesca Denoth of the Italian National Research Council, is reported in the Nov. 16 issue of the online journal PLoS ONE.