Definitions 150

Epidemiology 150

Evaluation 151

Treatment 152

Complications 153

Weight gain in an individual is the result of an energy intake from food in excess of energy expenditure. Unhealthy diets and lack of physical activity are considered to be the leading causes of avoidable illness and premature death in Europe, and the rising prevalence of obesity is a major public health concern. There is a strong tendency for excess weight to continue to accumulate from childhood through to middle age. While 40–70% of the variation in fat mass between individuals may be genetically determined, environmental factors remain crucial. Important lifestyle choices predetermining health risks in adulthood are made during childhood and adolescence. Schools must come to play a key role in promoting healthy diets and enjoyment of physical activity....