The health concern is abdominal (belly) fat, which causes the waistline to expand. A waist circumference greater than 34.6 inches for women and 40 inches for men is associated with increased risk for cardiometabolic disease.
This type of fat—called visceral adipose tissue—accumulates deep in the abdomen and surrounds organs such as the liver, pancreas, and kidneys. Unlike fat stored just under the skin, visceral fat is metabolically active and inflammatory.
“BMI doesn’t address any of that—it doesn’t address how much adipose tissue a person has, or importantly, where that fat is located,” Dr. Faridi says. “We know this extra fat tissue in the belly is not benign—it can contribute directly to disease.”
Obesity is linked to more than 200 conditions, including heart disease, diabetes, high blood pressure, fatty liver disease, sleep apnea, osteoarthritis, and certain cancers.
Waist circumference thresholds vary by population. For example, recommended cutoffs are lower for Asian adults—31.5 inches for women and 35.4 inches for men—because diabetes and related conditions tend to develop at lower body weights.
