BMI was originally developed by dietitians, aka people who make money when “overweight” people want to lose weight. Their profession incentivized the developers of the BMI scale to bias it towards “average” being less than average. This would be all well and good if “average” actually meant “healthy”, but you are, in fact, much more likely to die if you come in just under the “healthy weight” range than if you do if you’re in the first part of the “obese” range.

Obese is better than Underweight

Ranges

  • Underweight: BMI is less than 18.5
  • Normal weight: BMI is 18.5 to 24.9
  • Overweight: BMI is 25 to 29.9
  • Obese: BMI is 30 or more

BMI is measured in SI Units - Kg/M^2. Weird. Actually not weird, that’s exactly how it’s calculated:

So, for me, right now that’s:

I’m “healthy” now. According to their logic, if I gain 5 more pounds I’ll be “at risk”, but if I lost 50 pounds I’d still be “healthy”.


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