How useful is the body mass index (BMI)?

Robert H. Shmerling, MD

Faculty Editor, Harvard Health Publishing

The body mass index (BMI) has long been considered an important way to gauge your risk for many chronic conditions, from arthritis to sleep apnea to heart disease. But like all medical measures, BMI is not perfect — and a recent study has revealed that BMI alone may not be a solid measure of cardiovascular health. Here, we’ve examined the pros and cons of the BMI, and whether it’s a number worth knowing.