Having a large belly -- even with a healthy body mass index -- can take years off a person's life, U.S. researchers say.
Lead author Dr. James Cerhan, a Mayo Clinic epidemiologist, and colleagues reviewed data from 11 different studies, involving more than 600,000 people from around the world.
The review, published in Mayo Clinic Proceedings, found men with waists 43 inches or greater in circumference had a 50 percent higher mortality risk than men with waists less than 35 inches, and this translated to about a three-year lower life expectancy after age 40.
In addition, 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, the review said.
The increased mortality risk rose in a linear fashion -- for every 2 inches of greater circumference, mortality risk went up about 7 percent in men and about 9 percent in women.
Another key finding was elevated mortality risk with increasing waist circumference was observed at all levels of BMI, even among people who had normal BMI levels.
Because of the large size of this pooled study, the researchers were able to clearly show the independent contribution of waist circumference after accounting for BMI, Cerhan said.
"BMI is not a perfect measure," Cerhan said in a statement. "It doesn't discriminate lean mass from fat mass, and it also doesn't say anything about where your weight is located. We worry about that because extra fat in your belly has a metabolic profile that is associated with diseases such as diabetes and heart disease."
