WHY IS BMI USED?
BMI correlates with risk of disease and death; for example, heart disease increases with increasing BMI in all population groups. Calculating BMI is simple, rapid, and inexpensive. BMI correlates well with total body fat for the majority of people. DETERMINING BMI BMI is a measure of weight in relation to height: BMI = weight (kg)/height (m)2 or BMI = (weight (pounds)/height (inches)2) x 703 As an alternative to calculating BMI, tables to determine BMI are commonly available(www.nhlbi.nih.gov/guidelines/obesity/bmi_tbl.htm). CLASSIFICATION OF OVERWEIGHT AND OBESITY BY BMI In adults: Healthy weight 18.5-24.9 Overweight 25.0-29.9 Obesity Class I 30.0-34.9 Class II 35.0-39.9 Class III >40.0 In children and adolescents aged 6 to 19 years, overweight has been defined as a sex- and age-specific BMI at or above the 95th percentile, based on revised Centers for Disease Control and Prevention growth charts (www.cdc.gov/growthcharts). BMI has some limitations in that it can overestimate body fat