AYESHA RASCOE, HOST:
More than 20 years ago, public schools in Arkansas began measuring students' height and weight. Then they send letters home with the child's body mass index as part of an effort to reduce childhood obesity. At least 23 states have adopted similar practices. Kavitha Cardoza reports the letters apparently have had no impact on weight loss and can have unintended consequences.
KAVITHA CARDOZA, BYLINE: Sixth-grade boys joke around as they line up to be measured. All want to be the tallest.
UNIDENTIFIED STUDENT #1: Just, like, a advantage. You can play, like, basketball.
UNIDENTIFIED STUDENT #2: A taller dude can get more girls because you're tall.
(LAUGHTER)
UNIDENTIFIED STUDENT #2: Shut up, guys. Shut up.
CARDOZA: Anndrea Veasley, the registered nurse at Mann Arts and Science Magnet Middle School in Little Rock, has the 11-year-olds come up individually. One boy slouches.
ANNDREA VEASLEY: Stand up straight for me.
CARDOZA: Next, Veasley asks him to step on a digital scale but backward so he can't see the numbers. She silently notes his measurements - 4'7" and 115.6 pounds.
VEASLEY: You are good to go. You want to put your shoes on.
CARDOZA: This child's parents are among thousands who receive a letter with their child's body mass index, or BMI, calculated. We're not using children's names because of the stigma and bullying associated with obesity. This BMI number also categorizes each child as normal, overweight or obese.
JOE THOMPSON: This is not a shaming effort.
CARDOZA: That's Dr. Joe Thompson, who leads the Arkansas Center for Health Improvement. He's the pediatrician who helped create the program back in 2003. But since then, the state's childhood obesity rates have risen from 21- to 24%. Multiple studies have shown that these fat letters, as they're sometimes mockingly called, have had no effect on weight loss.
THOMPSON: I don't think it was ever intended to be a singular magic bullet. This was just raising levels of awareness.
CARDOZA: Thompson says these letters can help warn parents if their child is at risk of developing serious health issues. Arkansas now measures all public school students in even grades every year, except for seniors. That's because they've almost graduated but also because of what Thompson calls their shenanigans.
THOMPSON: We had one school where many of the boys came in with leg weights on underneath their jeans. And when we went to analyze the data, we saw that clearly something was not right.
CARDOZA: Some experts have criticized the letters, saying they can lead to weight stigma and eating disorders.
KIMBERLY COLLINS: I'm making blackened salmon and rice and asparagus.
(SOUNDBITE OF GAS STOVE LIGHTING)
CARDOZA: Kimberly Collins has four children. She's received BMI letters every year flagging them as overweight. One of them, Lynn, is considered obese. Lynn says strangers often stare at her and pass comments.
LYNN COLLINS: On my birthday last year, I went to - had to get my allergy shots, and one of the nurses told me, you are getting chubbier, and that didn't make me feel the best.
CARDOZA: Mom Kimberly says reading the letters offended her.
COLLINS: 'Cause it made me feel like I wasn't doing my job as a mom. I felt judged. Even though it was not a blaming letter, it still felt that way.
CARDOZA: Collins already followed the recommended healthy practices for her kids, like lots of fruits and vegetables and after-school sports. She even signed up for nutrition classes.
COLLINS: But even that isn't enough to combat the issue that we're having.
CARDOZA: Unlike the Collins family, studies show few parents follow up with a health care provider or make changes. Hannah Thompson, a University of California Berkeley assistant professor, has studied BMI letters. She says, the big problem - most parents don't even remember getting one.
HANNAH THOMPSON: It's so low touch, it's really not very effective.
CARDOZA: An even bigger problem is what to do with the information.
THOMPSON: You find out your child is asthmatic, and you can get an inhaler, right? You find out that your child is overweight - what do you do?
CARDOZA: Collins says it's painful to see her soft-spoken and kind daughter Lynn, who's now 15, cover herself with her arms as if she's trying to hide. The teenager has begun sneaking food.
COLLINS: She won't turn the light on in the bathroom.
CARDOZA: She doesn't want to look at herself in the mirror.
COLLINS: She doesn't. And if I turn the light on in the bathroom, she yells at me.
CARDOZA: Some states have scaled back on BMI reporting. One school district in Wyoming used to include the numbers in report cards. They've stopped. Even Arkansas changed its rules to allow parents to opt out. For NPR, I'm Kavitha Cardoza.
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