New research published on September 1, 2026, indicates that for adults over 65, a high waist circumference is linked to a significantly increased risk of all-cause mortality, affecting both men and women. This finding contrasts with the study’s observation that a higher body mass index (BMI) may offer a protective effect against all-cause mortality in males over 65.
The study, which incorporated data from 6,905 individuals aged 65 and older between 2011 and 2024, suggests that while being overweight or having class I and class II obesity was associated with a 46% and 51% reduction in mortality risk respectively for males, a high waist circumference presented a 24% higher risk for men compared to those with a healthy waist size. A similar elevated risk was noted for women with larger waistlines.
Medical director Mir Ali, who was not involved in the study, noted that BMI is not an ideal measure and that a high waist circumference, typically indicating truncal obesity, is a better predictor of mortality risk. He explained that a higher waistline measurement often signifies problematic body fat surrounding vital organs such as the kidneys, liver, heart, pancreas, and digestive organs. Conversely, individuals with class I or II obesity who carry most of their weight in their hips and thighs, maintaining a relatively normal torso, likely experience less impact on their internal organs.
Cardiologist Jayne Morgan, also not involved in the study, highlighted that in older adults, some weight may actually be protective, potentially indicating less frailty or debilitating illness. The study also found that being underweight, regardless of waist circumference, carried the highest mortality risk. Morgan emphasized the particular concern of a 2-3 inch waist increase in perimenopausal and menopausal women, linking it to increased cardiometabolic risk, insulin resistance, elevated cholesterol, a pro-inflammatory state, and higher cardiac and stroke risk.
BMI, calculated from height and weight, can be misleading, especially for women. Morgan pointed out that some women with a normal BMI might have a redistribution of fat from hips to the abdomen, leading to increased visceral fat and higher cardiovascular risk despite being classified as normal. A high waistline circumference is defined as 40 inches or more for men and 35 inches or more for women, measured between the lower rib and the iliac crest.
