HELSINKI, FINLAND – A new study suggests that body mass index (BMI) may significantly overestimate childhood obesity, with the waist-to-height ratio proving to be a more accurate and accessible measure.
Published in the journal Obesity and Endocrinology, the research, a collaboration between the University of Eastern Finland and the Universities of Bristol and Exeter in the UK, found that BMI classified nearly three times as many children as overweight compared to the waist circumference-to-height ratio.
The study, which followed 7,600 children from the University of Bristol’s “Children of the 90s” cohort from ages 9 to 24, highlights a critical issue: BMI does not differentiate between muscle and fat mass, potentially leading to misclassification.
“Overweight and obesity in children and adolescents should not be diagnosed with BMI alone, but could be confirmed with waist-to-height ratio where a DEXA scan is lacking,” stated Dr. Andrew Agbaje, a physician and associate professor at the University of Eastern Finland, who led the research.
The findings reveal a significant discrepancy between the two measurement methods. Of the 1,431 children classified as BMI-overweight at age 9, only 25% had a waist-to-height ratio indicating high fat, and 11% had a ratio indicating excess fat. Conversely, of the 517 children classified as having a high fat waist-to-height ratio, 70% were also BMI-overweight, and 24% were BMI-obese.
The study also validated the waist-to-height ratio’s ability to predict health risks, demonstrating its association with prediabetes and type 2 diabetes in a separate group of US adults.
“Waist-to-height ratio is an affordable and universally accessible, accurate and precise tool for detecting high and excess fat in children and adolescents,” Dr. Agbaje explained.
While dual-energy X-ray absorptiometry (DEXA) remains the gold standard for measuring body fat, its high cost and limited availability make the waist-to-height ratio a practical alternative. The study confirmed that the waist-to-height ratio can assess body fat with up to 85% accuracy compared to DEXA.
This research aligns with recent recommendations from organizations like The Lancet Commission on Obesity and the European Association for the Study of Obesity (EASO), which suggest that adult obesity diagnoses should not rely solely on BMI.
The UK National Institute for Health Care and Excellence has also recommended the waist-to-height ratio as a tool to predict health risks associated with central adiposity in children.
The study’s findings underscore the need for a more nuanced approach to assessing childhood obesity, potentially leading to more accurate diagnoses and targeted interventions.
More information can be found in the Obesity and Endocrinology journal, DOI: 10.1093/obendo/wjaf002.
Disclaimer: This news article is based on the provided information and should not be taken as medical advice. Consult with a healthcare professional for any concerns regarding your or your child’s health. The study findings represent a specific research outcome and may not be universally applicable. Further research and professional medical guidelines should be considered for comprehensive assessments.