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This Eighth-Grade Girl's Explanation Of Body Mass Index Is Going Viral

BMI says what?

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Here's how the CDC defines body mass index:

"BMI is a person's weight in kilograms divided by the square of height in meters. BMI does not measure body fat directly, but research has shown that BMI is moderately correlated with more direct measures of body fat."

As NPR's Keith Devlin explains, "It makes no allowance for the relative proportions of bone, muscle and fat in the body. But bone is denser than muscle and twice as dense as fat, so a person with strong bones, good muscle tone and low fat will have a high BMI. Thus, athletes and fit, health-conscious movie stars who work out a lot tend to find themselves classified as overweight or even obese."

As Tessa explained to her teacher:

BMI is an outdated way of defining normal weight, under weight, over weight, and obesity by taking one person's height divided by their weight. One of the formula's obvious flaws, explains Alan Aragon, the Men's Health Weight Loss Coach and nutritionist in California, is that it has absolutely no way of discriminating fat and muscle. So, let's say there is a fairly athletic woman who maintains a decent diet, she's five feet, six inches, and she weighs 190 pounds, but 80% of her body is muscle. That doesn't matter when calculating BMI! This woman's BMI would be 30.7, and she would be labeled obese. Does that make sense to you? Because it sure doesn't make sense to me.


Despite being a great softball player, Tessa said she struggled with her body image.

At the beginning of the year, I started having very bad thoughts when my body was brought into a conversation. I would wear four bras to try and cover up my back fat, and I would try to wrap ace bandages around my stomach so I would look skinnier.

He did a couple tests and told me I was fine. He said though I'm a bit overweight, he's not going to worry about me based on how healthy I am. So this is where I don't calculate my BMI because my doctor, a man who went to college for eight years studying children's health, told me my height and weight are right on track. I am just beginning to love my body, like I should, and I'm not going to let some outdated calculator and a middle school gym teacher tell me I'm obese, because I'm not. My BMI is none of your concern because my body and BMI are perfect and beautiful just the way they are.


"We encourage [our kids] to be the best people they can be," she told BuzzFeed. "We tell them to be proud of who they are. If they ever have insecurities about something they have no control over, we point out everything about them they should be embracing instead. We try to guide them toward their goals and help them make a game plan to reach them. They know they'll always have our full support."

"These students already know where they fit in with everyone else," she told BuzzFeed. "They know what sizes the department stores keep downstairs and the ones they keep upstairs. This is like pouring salt in the wound. Especially for someone like my daughter who is bigger, but is strong, active, eats well, and has received a clean bill of health from her pediatrician."