The thing is, the guy who invented BMI explicitly and specifically said it wasn’t meant as a measure of individual risk.

It was meant as a measure of *population* risk and for public health usage, not diagnosis.

Doctors use it because it’s easier than actually getting out the calipers and checking body composition.

Then they use it to not bother with any diagnosis other than “fat,” especially for women and most especially for Black women.

(As a note, BMI also only works well for people of European descent because that’s the population it was developed for. It’s particularly inaccurate for people of African descent).