That there are people like The Rock, Hafþór Björnsson who have a high BMI but are otherwise healthy* does not take anything away from the fact that a high BMI is a pretty good indicator that you&#x27;re overweight or obese. It&#x27;s an imperfect measure but realistically if you&#x27;re at those Obese or above levels you&#x27;re either overweight and you know it, or an outlier and you know it.<p>* = I suspect that a good number of guys like this are taking substances that would damage them in other ways that could lead you to describe them as unhealthy, but as another commenter said that&#x27;s maybe not for BMI to measure.