BMIRatingWaist Size
< or = to
40 in. (men) or
35 in. (women)
> or = to
40 in. (men) or
35 in. (women)
18.5 or lessUnderweight--N/A
18.5-24.9Normal Weight--N/A
30.0-34.9ObeseHighVery High
35.0-39.9ObeseVery HighVery High
40 or greaterExtremely ObeseExtremely HighExtremely High

BMI is equal to or less than 18.5 (Underweight)
A lean BMI can indicate that your weight maybe too low. You should consult your physician to determine if you should gain weight, as low body mass can decrease your body's immune system, which could lead to ilness.
BMI Underweight Treatment

BMI is between 18.5 and 24.9 (Normal)
People whose BMI is within 18.5 to 24.9 possess the ideal amount of body weight, associated with living longest, the lowest incidence of serious ilness, as well as being perceived as more physically attractive than people with BMI in higher or lower ranges.

BMI is between 25 and 29.9 (Overweight)
People falling in this BMI range are considered overweight and would benefit from finding healthy ways to lower their weight, such as diet and exercise. Individuals who fall in this range are at increased risk for a variety of ilnesses.
Overweight Treatment

BMI is over 30 (Obese)
Individuals with a BMI over 30 are in a physically unhealthy condition, which puts them at risk for serious ilnesses such as heart disease, diabetes, high blood pressure, gall bladder disease, and some cancers. These people would benefit greatly by modifying their lifestyle.
Obesity Treatment