People with the largest waistlines have twice the risk of dying over a 10-year period compared with those sporting smaller midsections, according to a study published in Archives of Internal Medicine and reported by The Associated Press.

The belly fat that causes tummies to bulge is stored behind the abdominal wall. This type of fat is more harmful because it’s believed to secrete proteins and hormones that cause inflammation, interfere with insulin processing and raise cholesterol levels.

For the study, researchers from the American Cancer Society examined data from a nine-year study of more than 100,000 people (15,000 died during the study period). Scientists placed participants in three categories: normal, overweight and obese.

Next, researchers drew conclusions based on participants’ self-reported waist measurements, height and weight.

Researchers found that in all categories, a larger than average waist size was linked to a higher risk of death. (For men, that’s no more than 40 inches; for women, nothing over 35 inches.)

Furthermore, scientists found that a four-inch waistline increase boosted the risk of dying from 15 to 25 percent. 

Surprisingly, the strongest link (of 25 percent) was in women with a normal body mass index (a standard measure based on weight and height). The risks then climbed progressively with increasing waist size.

“Even if you haven’t had a noticeable weight gain, if you notice your waist size increasing, that’s an important sign,” said Eric Jacobs, PhD, an epidemiologist with the American Cancer Society, and lead author of the study. “It’s time to eat better and start exercising more.”

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