obesity definition for kids
Overweight and obesity are defined as abnormal or excessive fat accumulation that may impair health. Body mass index (BMI) is a simple index of weight-for-height that is commonly used to classify overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of his height in meters (kg/m2). The WHO definition is: 1  a BMI greater than or equal to 25 is overweight. 2  a BMI greater than or equal to 30 is obesity.