Doctors use Body Mass Index - or BMI - to assess a person's level of body fat.
But new research from UCLA says this screening tool misclassifies a lot of people.
Some are told they're obese when they're actually healthy, based on other factors.
Others might be told they have a healthy weight, when they have underlying medical problems.
Southern California Public Radio's health reporter Rebecca Plevin has been looking into the hullabaloo surrounding the BMI.
She's here to explain why you might want to take your BMI with… a grain of salt.
To find out more, you can read her full blog post.
So BMI is a less than perfect way to judge body fat. But just how damaging might this index be?
And what might be a better option to determine if a person is overweight?
Dr. Deborah Burnet is a professor of medicine and pediatrics at the University of Chicago School of Medicine. She spoke with Take Two's Alex Cohen for more.
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