Americans keep putting on the pounds — at least according to a report released this week from the Trust for America's Health. The study found that nearly two-thirds of states now have adult obesity rates above 25 percent
But you may want to take those findings — and your next meal — with a grain of salt, because they're based on a calculation called the body mass index, or BMI.
Weekend Edition math guy Keith Devlin graded the body mass index and tells host Scott Simon that it fails on 10 grounds:
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.
The BMI was introduced in the early 19th century
He produced the formula to give a quick and easy way to measure the degree of obesity of the general population
In other words, it is a 200-year-old hack.
2. It is scientifically nonsensical.
3. It is physiologically wrong.
4. It gets the logic wrong.
clipped from: www.npr.org