[MrsD2008]

I hear a lot of people grumble about Body Mass Index. Is there some research the BMI is outdated? And if it is, why is WW still basing final goals on it?

I met my 10% yesterday, so I have been thinking about making my final goal. My doctor said she wouldn't like to see me below 130, but according to BMI, I shouldn't be above 128. When I first started, I really wanted to work toward 125. I was about 118-122 when I was in my first and second years of high school--but I was a lot younger then!

I've lost 23 lbs so far and I am starting a walking regimen this week. I've made a lot of changes in my eating habits and what foods I do reach for. In my head, I have reached my ultimate goal. So why is that 2-5 pounds messing with my head?!

[Heather]

Outdated? Try, never designed for how we use it.

BMI wasn't designed for individuals but has been co-opted for them because it's very easy to measure and does have correlates with health outcomes.

If you're interested, here's a decent article about the history and use of BMI: http://www.slate.com/id/2223095/

One excerpt:
"Belgian polymath Adolphe Quetelet devised the equation in 1832 in his quest to define the "normal man" in terms of everything from his average arm strength to the age at which he marries. This project had nothing to do with obesity-related diseases, nor even with obesity itself. Rather, Quetelet used the equation to describe the standard proportions of the human build—the ratio of weight to height in the average adult. Using data collected from several hundred countrymen, he found that weight varied not in direct proportion to height (such that, say, people 10 percent taller than average were 10 percent heavier, too) but in proportion to the square of height. (People 10 percent taller than average tended to be about 21 percent heavier.)"

And later:
"Keys had never intended for the BMI to be used in this way. His original paper warned against using the body mass index for individual diagnoses, since the equation ignores variables like a patient's gender or age, which affect how BMI relates to health. It's one thing to estimate the average percent body fat for large groups with diverse builds, Keys argued, but quite another to slap a number and label on someone without regard for these factors."