[brmgb]

There is little point of doing a study based on BMI when what you want is body fat. BMI is imperfect. It’s fine when you want to give people a quick metric for them to assess their fitness by themselves. People who are extremely fit with a high BMI already know they are extremely fit after all. It’s not fine when you want to analyse the effect of different life styles.

[heyoni]

It’s easier to gather hundreds of people’s BMI for a study than it is to measure fat, which can also be misleading depending on the method used.

[brmgb]

It's even easier to not do the study if you are going to use bogus data anyway.