alt Hacker News> The most notorious of which is BMI; it is practically a category error to infer someone's health or risk by individual BMI, and yet doing so remains widespread amongst people that are supposed to know better.
BMI works fine for people who aren't very muscular, which is the great majority of people. Waist to height ratio might be more informative for people with higher muscle mass.
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My understanding is that it doesnt even do that, because it creates false negatives for the so called skinny fat body type: significant visceral fat mass, which is what we are concerned about, but not much muscle or peripheral fat mass, thereby not being flagged by BMI screens, even though they are at risk.
I dunno, basing life decisions off a metric that has a fudge factor built into it to make the regression work feels sub-optimal to me.
As a person who has been told I'm "morbidly obese" for decades now, I will say that doctors at almost every level look at your chart not you. I've been told time and time again that until I get my weight under control, my health will suffer.
I'm 5'8" and weigh on average 210lbs. My BMI isn't even morbidly obese, it is 31, which is just "regular" obese, but on top of that, a DEXA scan shows that I am actually only 25% body fat, with only 1lb of visceral fat.
Doctor's don't care about that, they see on the Epic chart that my BMI is > 30 and have to tell me some spiel about a healthier lifestyle so they check check off a checkbox and continue to the next screen.