Causes and consequences of overweight in children

B. Koletzko, Munich

The increasing prevalence and severity of overweight and obesity are alarming not only in adults, but also in children and adolescents. In Germany more than 10 % of primary school children are overweight, with an increasing trend. Current therapeutic approaches are far from satisfactory, therefore, prevention is of utmost importance.

Effective measures of primary prevention must address the various causal factors of the overweight epidemic. Many studies have shown an increased risk of overweight in the children of overweight parents, especially overweight mothers, demonstrating the significance of a genetic predisposition, but also of long-term effects of metabolic and hormone factors during pregnancy. Socio-economic conditions and family traditions are of some significance as well. In primary school children of non-German families, overweight is nearly twice as prevalent as in children of German families.

Overweight is mainly due to a disproportion of energy expenditure and energy intake. Increasingly sedentary activities with low physical activity in children, and accordingly low energy expenditure, low muscle mass and low combustion of fat are essential risk factors.

Energy intake depends on eating habits and on the amount and composition of food and drinks ingested. The eating behaviour of children has greatly changed during the last years. Family meals and food prepared in private households are more and more replaced by snacking and by consumption of ready-to-eat foods, such as high calorie snacks consumed at school, during leisure time and while watching TV. Commercially prepared ready-to-eat foods show a trend towards larger portion sizes, which supply more energy.

Children in Germany consume high fat intakes near 40 energy percent of energy intake. Population studies demonstrated that children and adults with high fat intakes have a higher probability of overweight, whereas overweight prevalence decreases with increasing carbohydrate intake . Effective prevention is based on an analysis of the causes of overweight. There are interventions with a favourable cost-benefit-ratio for primary prevention. In view of an imminent overweight epidemic in children, further development and application of prevention strategies with demonstrated efficacy are urgently needed.

Keywords: Overweight / children / causes / consequences

Sie finden den Artikel in deutscher Sprache in Ernährungs-Umschau 03/05 ab Seite 94.