Men and women with large waist were more likely to die younger. They are likely to die from illnesses such as heart disease, respiratory problems and cancer after accounting for body mass index, smoking, alcohol use and physical activity, said researchers from Mayo Clinic.
"BMI does not discriminate lean mass from fat mass and it also does not say anything about where your weight is located. The extra fat in your belly has a metabolic profile that is associated with diseases such as diabetes and heart disease," explained James Cerhan, a Mayo Clinic epidemiologist and lead author of the study.
The researchers pooled data from 11 different studies, including more than 600,000 people from around the world.
They found that men with waists 43 inches or greater in circumference had a 50 percent higher mortality risk than men with waists less than 35 inches.
This translated to about a three-year lower life expectancy after age 40.
Women with a waist circumference of 37 inches or greater had about an 80 percent higher mortality risk than women with a waist circumference of 27 inches or less.
And this translated to about a five-year lower life expectancy after age 40.
Importantly, risk increased in a linear fashion such that for every two inches of greater circumference, mortality risk went up about seven percent in men and about nine percent in women.
Another key finding was that elevated mortality risk with increasing waist circumference was observed at all levels of BMI, even among people who had normal BMI levels.
Physicians should consider both BMI and waist circumference as part of risk assessment for obesity-related premature mortality, said the study published in the journal Mayo Clinic Proceedings.