Body mass index may not be an accurate measurement for health.
Researchers at the University of Pennsylvania found that although an obese BMI is usually associated with high risk of heart disease and diabetes, some people with an obese BMI have improved metabolisms and reduced risk of heart disease.
Despite the widespread popularity of using BMI to gauge a person’s health, said Joslyn Ahlgren, a UF lecturer of anatomy, physiology and exercise science, the two are not equal.
“If you look at a bodybuilder, they have very little fat on their bodies, but their BMI is very heavy: obese or morbidly,” Ahlgren said. “Their actual body composition is very good.”
Ahlgren said there are other ways to evaluate health. For example, looking at factors such as family history and general activity can reveal a lot.
“You determine BMI by taking body weight in kilograms divided by height in meters squared,” she said. “It’s not the world’s best index for health.”
But 21 states — including Florida — have been sending parents what have been nicknamed “fat letters,” indicating students’ BMI and weight category. The BMI screening process was created in schools to inform parents about childhood obesity; about 31.9 percent of children and adolescents are overweight or obese, according to an article from The American Academy of Pediatrics.
BMI is the best measurement currently available, said Alexandra Sifferlin, a Time.com reporter who wrote an article for Time Health & Family about the subject.
“It’s the easiest and the cheapest, but it certainly isn’t the best for health,” she said.
The Centers for Disease Control and Prevention, or CDC, does not classify BMI as a measure for health.
“CDC uses BMI for gathering obesity prevalence data since it is an easy and economical way to ascertain obesity prevalence at a population level,” wrote Karen Hunter, senior press officer for the CDC, in an email. “At an individual level, BMI can be used as a screening tool but is not diagnostic of the body fatness or health of an individual.”
