News flash: the American Medical Association finally managed to accept and acknowledge publicly what many experts have been saying for decades (backed by truckloads of data and studies): BMI (body-mass-index) is itself not a good measure of overall individual patient health. In this NY Times article, a medical researcher specializing in health and body weight was quoted as saying:
“The B.M.I. is just a very poor measure of general health… Someone with an elevated B.M.I. may be perfectly healthy.”
This same article quoted one of my favorite body weight researchers, UCLA’s Janet Tomiyama whose work focuses on the harmful health and health equity consequences of stress, dieting, and fat shaming.
“[it’s] not this magic or powerful number that dictates how healthy or sick you’re going to be,” said A. Janet Tomiyama, a professor of psychology at the University of California, Los Angeles, who has studied B.M.I. and said she was “in shock” about the new policy. “For the longest time, I’ve been in this emperor-has-no-clothes situation, where I just couldn’t understand why really smart physicians continue to rely on something that was so clearly flawed.”

You may be wondering, though, why this organization, after resisting studies for so long, has finally changed its tune on BMI. Here’s a bit of what the American Medical Association had to say:
Under the newly adopted policy, the AMA recognizes issues with using BMI as a measurement due to its historical harm, its use for racist exclusion, and because BMI is based primarily on data collected from previous generations of non-Hispanic white populations.
Also:
[BMI] does not account for differences across race/ethnic groups, sexes, genders, and age-span.
Oh, really?
Honestly, I’m glad and relieved that the AMA is finally finally finally openly (if grudgingly) acknowledging what researchers have known for decades was false and harmful about using BMI as a metric for individual health. If you’ve been reading this blog for more than a week, you’ve seen that we spend a lot of time identifying anti-fat bias and debunking specious claims about BMI. Here are a few posts we’ve written:
Fit, Fat, and What’s Wrong with BMI (Sam in 2012)
A brief note from the BMI war front (Catherine in 2016)
“Obese” is a bad word– it’s got to go (Catherine in 2015)
There are literally dozens of posts on this topic, written by all of us at one time or another. One place to browse through them is here. Of course, it’s one thing for us– the readers and writers of this blog to know the limitations and flaws of using BMI in medical contexts. It’s another thing to a) get the message out to the general populace; and b) change clinical practice to phase out BMI-assisted fat shaming in health care. I’m hoping this one step will be followed by more.
Make sure to bookmark this post, and take it with you next time you see your healthcare provider. Let us know how the conversation goes.