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by jdeisenberg 1222 days ago
Some interesting information about the BMI in this opinion piece: https://www.npr.org/templates/story/story.php?storyId=106268... (Top 10 Reasons Why The BMI Is Bogus)
3 comments

Sorry, I think pretty much all those reasons are bogus. Yes, 100% agree that, as I said, it isn't a good metric for individuals, and I also agree that the actual calculation is weird - at the end of the day it's still just a ratio of height to weight.

But all of this nonsense nitpicking about bone density vs muscle vs fat is irrelevant when using it to look at large population cohorts over time. Looking at weight vs height is a good, easily calculable metric without needing to put everyone in a float tank.

The US BMI has skyrocketed over the past 50 years solely because we've gotten a ton fatter. There have also been plenty of corroborating studies that we've also gotten a ton weaker, e.g. studies that look at average grip strength.

Any studies in particular of interest on the strength metrics over time?
https://www.npr.org/sections/health-shots/2016/06/13/4815909...

There are links to the source study in that article.

The very first reason is "1. The person who dreamed up the BMI said explicitly that it could not and should not be used to indicate the level of fatness in an individual.", which is the exact point being made: at a population level BMI is useful.

Additionally, BMI is imprecise, but imprecise doesn't mean useless. If you took a random sample of people with a BMI of 40+ from across the whole population, almost none of them would be near optimal healthy weight; a random sample of 30+, still relatively few. Those few who are healthy at that BMI know it. BMI's maybe not so useful for someone who's hovering around 19 or 28, but at the extreme edges it's very indicative of body fat.

In case I can save anyone a click, there isn’t a single sentence of that article worth reading.

The author simply fails to understand that BMI is a helpful indicator for population metrics, and contorts into crazy positions to fill out a “top 10” list