While this is technically true, in practice, this argument actually works in the opposite direction.
It is extremely rare for a human to have an obese BMI, while having low body fat %. This essentially only occurs in Bodybuilders. If you are in this group, noone will ever misidentify you as obese, because you will be fucking ripped. The book “Overcoming Fatlogic”, which I strongly recommend, has some images of extremely fit people with normal BMIs that really make that point emotionally/visually too, beyond the strong statistical support.
On the other hand, it is becoming increasingly common in our sedentary society for people to have a normal BMI, but be “skinnyfat”, that is, having such little muscle mass that their fat % still makes them sick.
Body fat percentage is also tricky to measure (body fat scales are unreliable, calipers are unreliable, visual assessments by pros are unreliable, and all of these require either expensive devices or professionals, or both); BMI is trivial to measure. For any really large study, it is the only thing that is feasible.
On a population level, BMI will under-, not overestimate obesity. It is a useful tool, and if BMI seems bad, the situation on a population level will currently be even worse.
While this is technically true, in practice, this argument actually works in the opposite direction.
It is extremely rare for a human to have an obese BMI, while having low body fat %. This essentially only occurs in Bodybuilders. If you are in this group, noone will ever misidentify you as obese, because you will be fucking ripped. The book “Overcoming Fatlogic”, which I strongly recommend, has some images of extremely fit people with normal BMIs that really make that point emotionally/visually too, beyond the strong statistical support.
On the other hand, it is becoming increasingly common in our sedentary society for people to have a normal BMI, but be “skinnyfat”, that is, having such little muscle mass that their fat % still makes them sick.
Body fat percentage is also tricky to measure (body fat scales are unreliable, calipers are unreliable, visual assessments by pros are unreliable, and all of these require either expensive devices or professionals, or both); BMI is trivial to measure. For any really large study, it is the only thing that is feasible.
On a population level, BMI will under-, not overestimate obesity. It is a useful tool, and if BMI seems bad, the situation on a population level will currently be even worse.