What is Obesity?

Defining "Adult Overweight" and "Obesity"

Weight that is higher than what is considered as a healthy weight for a given height is described as overweight or obese. Body Mass Index, or BMI, is used as a screening tool for overweight or obesity.

Adult Body Mass Index (BMI)

BMI image

Body Mass Index (BMI) is a person's weight in kilograms divided by the square of height in meters. A high BMI can be an indicator of high body fatness. BMI can be used as a screening tool but is not diagnostic of the body fatness or health of an individual.

To calculate BMI, see the BMI Calculator or determine BMI by finding your height and weight in this BMI Index Chart.

If your BMI is less than 18.5, it falls within the underweight range.
If your BMI is 18.5 to 24.9, it falls within the healthy weight range.
If your BMI is 25.0 to 29.9, it falls within the overweight range.
If your BMI is 30.0 or higher, it falls within the obese range.

Note: At an individual level, BMI can be used as a screening tool but is not diagnostic of the body fatness or the health of an individual. A trained healthcare provider should perform appropriate health assessments in order to evaluate an individual's health status and risks.

Waist Circumference

Man measuring waist

Measuring waist circumference helps screen for possible health risks that come with overweight and obesity. If most of your fat is around your waist rather than at your hips, you’re at a higher risk for heart disease and type 2 diabetes. This risk goes up with a waist size that is greater than 35 inches for women or greater than 40 inches for men. To correctly measure your waist, stand and place a tape measure around your middle, just above your hipbones. Measure your waist just after you breathe out.