Overweight and obesity is measured with Body Mass Index (BMI). BMI is calculated as weight divided by height multiplied with height. BMI is calculated on basis of self-assessed height and weight. The measure does not distinguish between fat and muscle mass. Statistics Norway uses the cut-off points recommended by WHO-EURO: Some overweight (BMI=25-26.9), overweight (BMI=27-29.9), obese (BMI=30 or above).