How accurate is it, in practice, for a given individual? I'm not that out of the ordinary proportion wise. I have a slightly longer torso and arms versus my legs, a somewhat muscular-ish baseline and broad shoulders, but I accumulate fat almost exclusively abdominally. My teenage self, lifetime peak of my fitness, no visible body fat, hyperactive football player, qualified as solidly overweight. If I was to listen to it, I'd be called obese before I noticeably start to show body fat.
I often wonder far from the median I am in this regard. I was under the impression that it was pretty accurate for assessing populations, but fell apart very quickly at the individual level. How many "normal"/otherwise healthy people do fall outside BMI's numbers?
It’s a tool not the tool. If you have obese BMI you can… look in the mirror and see how accurate it is. If you aren’t sure take one of the dozens of other tests. People focus too much on it being a one stop shop - it’s not. It’s the start of a dialogue with your pcp and self on assessing your health that’s highly correlated with poor health outcomes.
If bmi says you're obese, you very likely (~95%) are. The problem is that bmi only catches about half of people who are obese.
https://www.nature.com/articles/s41598-020-69498-7
I haven't been down in the normal BMI range since 8th grade. And I was measured at 6% body fat my senior year in high school! BMI has always run several points high for me. For that reason, I've always liked waist to height ratio better.
How about other categories, in either direction? I seem to remember it to be a lot less clean cut at the normal/overweight boundary.
It's not really intended to be applied to individuals at all, but if you're in the "healthy" BMI range then you are probably fine just not thinking any further about your weight and doing something like measuring your body fat percentage would just be a waste of time and a source of stress for some people. If you're outside that range, then it is worth doing some of the more involved things to judge if your weight is healthy.
It isn't accurate. It is a statistical tool meant for easily measuring populations of people. It does not apply in any meaningful way to individuals.
That was my impression as well. I'm just wondering if there are actual numbers to gauge by how much. I'd find it almost concerning anyone would draw any conclusions from it if it's not significantly any better at predicting health outcomes than a coin toss.