Measuring waist size may be one of the simplest and most effective ways to detect obesity-related health risks, according to a study by Rutgers Health researchers.
The study , published in JAMA Network Open , found that combining body mass index (BMI) with waist circumference, or using waist circumference alone, performed as well as a newly proposed obesity definition that incorporates multiple body measurements.
The findings suggest that a quick waist measurement could provide clinicians and patients with a practical tool for identifying potentially unhealthy amounts of body fat and associated health risks.
“Pay attention to the need to loosen your belt or get bigger pants,” said Aayush Visaria , a faculty member of the Rutgers Health-RWJBarnabas Health Center for Climate, Health, and Healthcare and lead author of the study. “Although clothing size isn’t the same as a proper waist circumference measurement, it can be an early sign of unhealthy amounts of body fat. Measuring your waist, along with your weight, can help identify health risks earlier and provide an opportunity to reduce your risk of diabetes, heart disease, stroke and some cancers.”
Rutgers Health researchers evaluated data from 1,900 U.S. adults ages 20 to 59 who participated in the National Health and Nutrition Examination Survey. The study compared several approaches to diagnosing obesity along with a highly accurate method for measuring body fat.
Researchers examined a recently proposed obesity framework from a multidisciplinary group of independent experts which incorporates BMI, waist circumference, waist-to-height ratio and waist-to-hip ratio. While that framework identified more people with excess body fat, researchers found that simpler approaches achieved similar accuracy.
A definition based on either BMI or waist circumference showed better balance between correctly identifying people with obesity and avoiding false-positive diagnoses. Waist circumference alone performed nearly as well.
The researchers noted that hip circumference, one of the measurements required by newly proposed framework, is rarely collected in routine clinical practice. Waist circumference, however, is increasingly recognized in clinical guidelines and is relatively easy to obtain in primary care settings, the researchers said.
“Our findings show that you don’t necessarily need multiple complex measurements to identify obesity-related health risks,” said Visaria, who also is an instructor in the Department of Medicine at Rutgers Robert Wood Johnson Medical School . “A waist measurement provides much of the information needed and is feasible for clinicians and patients alike.”
The study also found that BMI alone missed a substantial number of people who met body-fat criteria for obesity, reinforcing concerns that BMI doesn’t fully capture differences in body composition or fat distribution.
Researchers said the results could help inform future obesity screening recommendations and support broader use of waist measurement in routine health care.
The study is coauthored by Soko Setoguchi of the Rutgers Center for Climate, Health, and Healthcare; Ethan Halm of Rutgers Health: and Douglas Corsi, Dylon Patel, Keerthana Kesavarapu and Jeffrey Carson of Rutgers Robert Wood Johnson Medical School.
JAMA Network Open
10.1001/jamanetworkopen.2026.27738
Data/statistical analysis
People
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Dr Setoguchi reported receiving grants from Daiichi Sankyo and Pfizer Japan and personal fees from Merck and Regeneron outside the submitted work. No other disclosures were reported.