BMI for Adults
What is BMI?
Body Mass Index or BMI (wt/ht2), based on an individual's height and weight, is a helpful indicator of obesity
and underweight in adults.
Determine BMI
BMI can be determined by using a hand-held calculator, looking it up on a table.
BMI compares well to body fat but cannot be interpreted as a certain percentage of body fat. The relation
between fatness and BMI is influenced by age and gender. For example, women are more likely to have a
higher percent of body fat than men for the same BMI. At the same BMI, older people have more body fat
than younger adults.
BMI is used to screen and monitor a population to detect risk of health or nutritional disorders. In an
individual, other data must be used to determine if a high BMI is associated with increased risk of disease and
death for that person. BMI alone is not diagnostic.
How does BMI relate to health among adults?
A healthy BMI for adults is between 18.5 and 24.9. BMI ranges are based on the effect body weight has on
disease and death.
A high BMI is predictive of death from cardiovascular disease. Diabetes, cancer, high blood pressure and
osteoarthritis are also common consequences of overweight and obesity in adults. Obesity itself is a strong
risk factor for premature death. 5
Body Mass Index Formula
English Formula
BMI =
[Weight in pounds ÷ Height in inches ÷ Height in inches] x 703
Example
A person weighing 210 pounds and 6 feet tall would have a BMI = 210 pounds divided by 72 inches divided
by 72 inches multiplied by 703 = 28.5
BMI Cutpoints for Adults
We interpret BMI values for adults with one fixed number, regardless of age or sex, using the following
guidelines:
Underweight BMI less than 18.5
Overweight BMI of 25.0 to 29.9
Obese BMI of 30.0 or more