I though I was clear about this, but I'll reiterate.

1. That the heuristic is accurate.
2. That the heuristic is more accurate than other easily applied heuristics.
3. That when the heuristic makes categories, the categories are backed by studies. These studies would show a statistical increase for specific health outcomes above this cutoff. That line would be tested relative to other proximal lines.
4. These heuristics would include different recommendations for different populations such as race, biological sex, and age.

A better alternative, as I had previously linked to, would be abdominal fat as measured at the waist. Easy heuristic and closely correlated to CVD.

All of what you say is true, but you're not address my particular issues.

I appreciate the systematic review and meta-analysis. It's a good starting statement and if I worked with children, I would look at the paper more closely. As a whole, these studies don't address the most at risk groups with a high level of evidence. Perhaps that last paper will be part of a meta-analysis that gives clearer evidence of BMI indicating CVD in children. This would be great.

I focus on medical practices because it's my area of expertise and where I do my work. So I see the negative effects of people's conceptions around weight, BMI, obesity, and how difficult it is to change even with the best applied efforts. I wrote my initial response when I saw an avalanche of self-righteous, care trolling with vague allusion to science and medicine with a level of certainty that isn't warranted. At best, I was being confrontationally polemical, at worst, I lack nuance or sensitivity to work in the field.

The ease at which people fat shame and delude themselves that they are helping is astounding. I was a little surprised to see it on Lemmy.

Admittedly, my statistical training isn't the best, but I appreciate the role it plays in making sense of large datasets. Still, I appreciate the reminder to dive deeper into how statistics are used in observational studies. For me, at least, I wish that much of this was done before the wide deployment of BMI in the populous. I'm not saying that fat-shaming wouldn't continue, but there doesn't need to be poorly applied scientific ammunition either.

PS. You might like this study that examined some of the boundaries for BMI.