The Body Mass Index (BMI) is a ratio obtained from 2 variables, the weight in kilograms divided by the height in meters squared. This ratio should be documented in all patients together with the vital signs and body measurements of the day. In addition, the BMI should be included in the nutritional assessment of patients with malnutrition and with obesity (including morbid obesity). The BMI is essential to differentiate morbid obesity (BMI>40) from lesser degrees of obesity. Finally, although the BMI is not part of the diagnostic criteria for malnutrition, it can serve to support its diagnosis.
Marco A. Ramos MD, CCDS