But it differs, especially for people with more muscle mass.   Yeah, I think that's what this study acknowledges. When the current cutoffs were created the average person had more muscle mass (and less fat...) and if you do, you can obviously have a higher BMI before it starts to be dangerous, since what's dangerous is the body fat %. Now most people sit inside, do not move and if they do they walk a few steps before getting into a car. Since muscle mass has dropped the limits should be redefined, and this is most apparent in women since without the natural testosterone levels of men they naturally get very small muscles if they aren't worked. A woman with a healthy amount of muscle can still be healthy at 24.5 BMI, but sadly most women don't have that. By the way, have you used a scale that measures BF before? Was it good? I'm considering getting one to keep better track of my TDEE.