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One area where BMI is known to not be as accurate is people who have high muscle mass. I don’t think this can explain everything but it seems like it could contribute to understanding this statistic.

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> The report’s major recommendations include reviewing body composition standards, as BMI tends to underestimate obesity when compared to more high-tech body fat measurement devices

Per the article, the DoD is explicitly more concerned about BMI may even be underestimating obesity for their cohort.

This is true in general. Look [0]. Especially for women who are slightly overweight, BMI underestimates body fat. People complain that BMI isn't accurate, but it's not the dunk they think it is, more accurate measures often paint an even worse picture.

[0]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877506/

Most people don't have enough muscle mass to make any difference. An excess of muscle mass is also associated with a shorter lifespan. I have weight trained for years and have a BMI of 31, and have pretty low body fat; but that isn't healthy in the long term either.

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