• It’s rather trivial to find a study talking about BMI, but talking about it in extremes like this does no one any good. I would highly suggest you go educate yourself on public health or at least read something in the literature before making such extreme claims. To help you get started, here’s a fairly comprehensive review on BMI in the clinical context.

    You do bring up a good point in that it’s important how we use BMI and just what it represents. Major institutions such as the AMA have started to reassess exactly how BMI is interpreted (and providing guidelines) in the clinical sense, because there are problematic ways to use BMI. Of note, they do not advocate against using BMI, but rather it should be one of many indicators, as that’s the basis of differential diagnosis in the first place.

    • I’ve already educated myself on this stuff, and continue to do so as more information comes out, but thanks.

      The condescending tone is classic considering the thing you linked has right in it:

      “However, it is increasingly clear that BMI is a rather poor indicator of percent of body fat. Importantly, the BMI also does not capture information on the mass of fat in different body sites. The latter is related not only to untoward health issues but to social issues as well. Lastly, current evidence indicates there is a wide range of BMIs over which mortality risk is modest, and this is age related. All of these issues are discussed in this brief review.”

      It’s a poor indicator because it lacks scientific rigor, aka pseudoscience.

      • The question was whether it was a clinically relevant metric - it is absolutely a useful one. You are correct that it is not an indicator of percent of body fat, it was not designed to measure this and using it for this purpose is mislead. But there’s a world of difference between “it’s bad at measuring body fat” and “BMI is pseudoscience”. It’s unfair to characterize it as lacking scientific rigor because there are plenty of scientifically rigorous studies involving BMI. It is extremely useful as a clinical indicator of one’s health, in the same way that body temperature can tell us things in the context of other metrics and can also tell us some high level information about a person’s general health.

        But perhaps most importantly, it’s extremely useful when we come to population health where generalized indicators are often more useful than hyper-specific ones. Indicators which are easy to measure and gather from relevant data sources are also often more useful than ones which may be more accurate on a per-individual basis, but less important when measuring the health of entire populations. I apologize for any condescension in my comment, I was suggesting that you become more educated in matters of public health because indicators like BMI are invaluable in this space.

        • Feel free to explain instead of being condescending for no reason, then.

          Like I said I’m willing to learn, but from wiki -

          Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable claims; reliance on confirmation bias rather than rigorous attempts at refutation; lack of openness to evaluation by other experts; absence of systematic practices when developing hypotheses; and continued adherence long after the pseudoscientific hypotheses have been experimentally discredited.

          If you can tell me how the things I listed don’t fit into that definition, great. Please do so.

          • I mean, BMI was openly developed, is systematically calculated and described, has been open to evaluation by experts for decades, and has been part of hypothesis development for similar decades. It is, in fact that systematic study that revealed where its use as an estimator or predictor of health had been overstated.

            When science falsifies a model, it does not retroactively make the model pseudoscience.

            • The ongoing adherence to it after being falsified, repeatedly through different studies, applies to BMI, which qualifies it as pseudoscience.

              So you are correct, falsification does not make something pseudoscience, but that’s not relevant in this case.