Rationale and definition:
This indicator tracks the share of a country’s population that is overweight or obese. Obesity at any age has significant effects on health, but is particularly damaging to children who often carry obesity into adulthood. The body mass index (BMI) is a measure of body fat based on height and weight that is calculated by dividing a person’s weight by their height squared. WHO defines overweight for adults as having a BMI greater than or equal to 25. A BMI greater than or equal to 30 defines obesity. Overweight in children is defined by WHO’s Child Growth Standards as the percentage of children aged 0-5 whose weight-for-height is above +2 standard deviations of the WHO Child Growth Standards median. Prevalence of overweight in adolescents is the percentage of adolescents who are one standard deviation above the BMI for age and sex.1
By sex, and age and urban/rural.
Comments and limitations:
The BMI is an imperfect measure, as it does not allow for the relative proportions of bone, muscle and fat in the body, and it ignores waist size, which is a clear indicator of obesity level.
Preliminary assessment of current data availability by Friends of the Chair:
Primary data source:
Potential lead agency or agencies:
WHO Indicator and Measurement Registry (2011).