Comment by adam_arthur
5 days ago
https://pubmed.ncbi.nlm.nih.gov/36756765/
Lowest risk is around 18-20 BMI in this recent study, which controls for many confounding factors not controlled for in other studies.
Other studies show slightly higher troughs, but often don't sufficiently control for correlation of weight with health in elderly people.
From this study: Estimates of mortality differences by body mass index (BMI) are likely biased by: (1) confounding bias from heterogeneity in body shape; (2) positive survival bias in high-BMI samples due to recent weight gain; and (3) negative survival bias in low-BMI samples due to recent weight loss
And if you follow the longevity/health space and studies as they come out, it's becoming pretty clear that bodyfat is objectively bad for you above a pretty low baseline.
It shows up in insulin resistance, heart markers, inflammation, and once you control for confounding factors sufficiently, mortality.
You likely won't become diabetic with a bodyfat of 25%, but all your health markers will be worse than somebody at 15%. This is measurable and clear.
If a single article in a low-impact journal cited by a handful of other articles is the only evidence you have, you're guilty of cherrypicking, I'm afraid. The article you're citing is clearly a response to the current medical consensus.
There are hundreds of studies indicating that each marginal additional unit of bodyfat is less healthy for you than not having it.
You are quoting poorly done and controlled BMI studies to dispute this, studies which look primarily at elderly people where weight is highly correlated with health to begin with and is not properly controlled for along every axis.
I'm not here to litigate it or convince you though.
"Less healthy" is distinct from "shortens lifespan" which was pretty much the entire point I was making.
I understand that the idea that there are well-controlled massive studies with enough power to detect differences from weight alone is appealing, but they simply aren't there -- which should tell you that even if the effect exists, it's not strong enough that it should be your primary motivation to lose weight. There are already plenty of reasons to lose weight that don't require lying to people about having a BMI > 20 shortening your lifespan.
BMI, in many cases, is considered a poor measure of health.
https://www.sciencefocus.com/comment/bmi-we-know-its-flawed-...
Yes it is but most of the studies use it, so that's the data we have.
And the OP implicitly referenced these studies in his claim that being overweight could be healthier (which comes up in BMI studies of elderly people that don't sufficiently control for confounding factors)
It was my intention to add some background detail, for anyone not aware, or wanting a side dive, about how BMI stands 'these days'. As such, it can be said the variables may be considered wider than they may appear at first (in the article conclusions). Which is a roundabout way of saying we all 3 are agreeing.
Je n’ai fait celle-ci plus longue que parce que je n’ai pas eu le loisir de la faire plus courte.