[graeme]

Ah I misread OP as saying people downplay obesity and don’t consider themselves fat. I took you to be giving an example of someone who thought they were not fat but were in fact fat.

Rereading OP’s comment I see they’re instead talking about people downplaying covid because they think it only affects people who are morbidly obese. My mistake.

Though, I suspect probably at least 80% of the people in the overweight/obese category legitimately have too much fat. Especially in america. Compared to the rest of the oecd, america has a much larger portion of “morbidly obese” within the obese category.

BMI does also underestimate obesity in some. On average it’s a reasonable definition of overweight/obese. The example you gave is an edge case, but the studies concern themselves with averages.

[oreaway]

I understand what you're saying and I see the confusion. To be more clear, I agree with you and BMI is a terrible measure of "overweight"/"obesity".

As someone who is 5'7" and 160 pounds, I'm considered "overweight", but if you saw me in person I'm almost certain you wouldn't think of me that way because I look quite fit. In reality, I have a decent amount of muscle mass from being physically active, but the BMI measure doesn't take into consideration muscle vs fat, and thus I am technically "overweight".

My point was not that everyone who is technically "overweight" is "fat" or "unhealthy", but rather that the COVID-19 reporting statistics that use those words are also using that "terrible measure" of BMI, and according to BMI, even typically-seen-as-healthy people fall under that "high risk" category, and people should be aware of that rather than assuming they are safe from COVID just because they are "fit".

[graeme]

I think you may be going a little far with this still though. Overweight is a risk factor, and someone who is overadipose absolutely is at higher risk.

For yourself, you would make the sensible adjustment of “well I’m not overadipose and therefore do not have higher risk from that factor”. That doesn’t mean you’d have no effects, it merely means you lack one risk factor.

But overadiposity absolutely is a risk factor and those in that group should be even more careful: the more overadipose, the more so.

BMI is used that way for studies because it’s a useful measure over groups. The exceptions run both ways and balance out. It just shouldn’t be applied blindly to individuals.