CALIFORNIA, USA — Losing weight is one of the most common New Year's resolutions. As you might be stepping on the scale and figuring out where you stand, it's important to understand why doctors calculate Body Mass Index.
Your BMI is a measurement of your weight over height in inches. If the calculation is under 18.5 you're considered underweight. If it's between 18.5 and 24.9 you're considered a normal weight. If it's between 25 and 29.9 you're considered overweight. Anything higher than that is in the obese category.
But the title doesn't always fit the body type. ABC10 health expert Dr. Tom Hopkins says BMI is a clinical tool. He said it's not designed to say what a person should weigh but asses their risk for health conditions like heart disease and diabetes.
"At one point, Roseanne Barr had the same Body Mass Index as Arnold Schwarzenegger, but they had a clear difference, so the BMI doesn't explain at all. So if you're someone who's very fit, muscular, and has a low body fat, you can have a significant BMI, but that BMI is not harmful to you. But if you are someone who has a higher BMI, and you really don't have a lot of muscle mass, but you have more fat than that, BMI is more clinically significant," Hopkins said.
Just last year The American Medical Association voted to move away from using BMI to measure weight. It says it's a useful tool for measuring large populations but not individuals. Some physicians say it's only helpful in certain scenarios.
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