Should Kids Be Weighed in Gym Class?

My friend was heartbroken. Her 8-year-old son had come home from school reporting that they were weighed in gym class, and that it had led to a discussion among the boys about their weights. It was the first time her son had realized that he was significantly heavier than most of his friends, and he came home that day with a brand-new message in his head: Being heavier wasn't a good thing.

Her story gave me flashbacks to my own gym class weigh-ins. I remember being called up one by one, how the scale was connected to a large digital readout big enough for everyone to see—and how, sadly, it felt like a competition among the girls to be the lightest.

Though it varies from state to state, many schools have a program in place to measure health and fitness in gym class. The assessment usually includes things like push-ups, flexibility tests, and a scale. Weight is then used with the child's height to calculate their body mass index (BMI). But is BMI a legitimate and important marker of health or a harmful practice that should be retired?

Measuring BMI can help determine if a child is at risk for developing chronic diseases such as metabolic syndrome, type 2 diabetes, and heart disease later in life, says Andjelka Pavlovic, Ph.D., director of youth research and education for the Cooper Institute, which developed FitnessGram by the Cooper Institute, the most widely-used assessment of student physical fitness.

"Aerobic capacity and BMI specifically have concrete health outcomes that can't be ignored," says Dr. Pavlovic. "There are very clear points at which BMI and poor cardiorespiratory fitness become health risks and it is important to identify those in children to prevent serious health problems down the road."

One in five children are currently considered obese (that's a BMI at or above the 95th percentile), according to the Centers for Disease Control and Prevention (CDC). Obese children are more likely to become obese adults, which is linked to a higher risk for conditions like heart disease and type 2 diabetes.

Pediatrician Natalie Muth, M.D., spokesperson for the American Academy of Pediatrics Section on Obesity and author of Family Fit Plan, says knowing students' BMI can be useful—but it has to be done right.

"BMI measurement in school can provide some benefits, provided the measurements are done privately and sensitively, free of judgement," says Dr. Muth. "When it's not done with the utmost care, the downside outweighs any upside and it's potentially harmful and stigmatizing." The CDC says that weighing students should not be done within sight or hearing distance of other students (in other words, the opposite of what I experienced as a student!).

Still, it's inevitable that some kids will compare numbers, and that can be potentially harmful. According to the National Eating Disorders Association, up to 60 percent of elementary school girls are worried about being too heavy. On the flip side, boys may feel shame if they're seen as too small or scrawny. That's why it's important to avoid any stigmatizing language.

"We shouldn't assume that higher weight kids are less healthy. That's weight stigma, which can increase the risk for eating disorders," says dietitian and exercise physiologist Rebecca Scritchfield, R.D., author of Body Kindness. Besides, she adds, some kids naturally trend higher on the growth curve, and that's normal for them.

And parents should be kept in the loop. Dr. Muth says that parents should be aware in advance that weights are being taken, how it's being done, and, ideally, have a chance to opt out. Dr. Pavlovic also says parents can request that their student be opted-out of the weight component of FitnessGram by sending a note into school.

The Bottom Line

Weighing students in school can be beneficial to help kids get on a healthier path, but it must be done properly. That means away from other students and without any weight stigma attached. Parents should also communicate with schools to know when and how weigh-ins are being done in order to decide whether or not their kid should participate.

Sally Kuzemchak, M.S., R.D., is a contributing editor for Parents magazine and a registered dietitian who blogs at Real Mom Nutrition, a "no-judgement zone" all about feeding a family. She is the author of The 101 Healthiest Foods For Kids and Cooking Light Dinnertime Survival Guide. You can follow her on Facebook and Instagram. In her spare time, she loads and unloads the dishwasher. Then loads it again.