Belly Fat May Predict Heart Disease Risk More Accurately Than BMI: Study

Forget the weighing scale for a second-your waistline may be telling your heart a much bigger story.

A new study suggests that where your body stores fat may matter more for cardiovascular health than body mass index (BMI) alone. Published in JACC, the research found that waist circumference (WC) and waist-to-hip ratio (WHR) can reveal hidden heart risks that BMI may miss.

BMI is widely used to classify people as normal weight, overweight or obese, but it does not show how fat is distributed. This matters because visceral fat around abdominal organs are more strongly linked to heart disease and diabetes than fat stored beneath the skin.

Researchers from the Cross Cohort Collaboration analyzed data from more than 260,000 people, followed for an average of 20 years. They examined nine cardiovascular outcomes, including heart attack, stroke, heart failure, atrial fibrillation and cardiovascular mortality.

The results exposed important gaps in BMI-based risk assessment. Among people classified as normal weight, 5% had a high waist circumference and 18% had a high waist-to-hip ratio. Among those considered overweight, 39% had high WC and 40% had high WHR.

Crucially, people with normal or overweight BMI but elevated central adiposity had a 15% to 50% higher risk for most of the cardiovascular outcomes studied.

The findings suggest that someone who appears to have a “healthy” BMI could still carry substantial cardiovascular risk if excess fat is concentrated around the abdomen.

Interestingly, some people classified as obese had relatively low waist measurements and did not show significantly higher risks for most outcomes compared with normal-weight individuals with low WC, except for all-cause mortality.

Researchers say clinicians should therefore consider waist circumference and waist-to-hip ratio alongside BMI when assessing cardiovascular risk. The study had limitations, including only one measurement of waist circumference and waist-to-hip ratio and a lack of detailed data on diet, physical activity and genetic obesity risk.

The takeaway? The scale tells you how much you weigh. Your waist may tell you more about where the risk is hiding.

REFERENCE: Zeina A. Dardari, et al.; Risk Reclassification Beyond BMI by Waist Circumference and Waist-to-Hip Ratio Across Nine Cardiovascular Outcomes: Results from the Cross-Cohort Collaboration; Journal of the American College of Cardiology; DOI: 10.1016/j.jacc.2026.05.050