Nov. 8, 2012 at 8:45 AM ET
By Katie Drummond
You've heard it before: Being overweight or obese is one of the biggest risk factors for developing type 2 diabetes. Turns out, it might be the type of excess body fat -- not simply the number on the scale--that puts you at an increased risk.
Obese patients with too much visceral fat -- a type of fat that surrounds internal organs -- were found to be at a significantly increased risk of developing diabetes, according to a new study in the Journal of the American Medical Association. In contrast, patients with excess subcutaneous fat -- the "pinchable" fat that's right underneath the skin -- didn't have that same danger.
"What we're seeing is that not all obese individuals are going to get diabetes," says lead study author James de Lemos, MD, a professor of internal medicine at the University of Texas Southwestern. "It's not just how heavy somebody is; you can't simply put them on a scale."
Researchers aren't sure why visceral fat seems to increase a patient's diabetes risk, but de Lemos suspects the fat secretes compounds that promote insulin resistance -- a key first step towards diabetes.
The good news? Visceral fat doesn't need to be a permanent addition to your waistline, according to Kerry Stewart, director of clinical and research exercise physiology at Johns Hopkins University School of Medicine. "The right choices seem to target visceral fat preferentially," he says. Make them consistently, and you can minimize that inner-belly bulge.
Here are three ways to attack the fat:
At the gym: Burn visceral fat using a one-two punch of aerobic exercise and weight lifting. "Physical activity seems to be the single best approach for targeting visceral fat," says Stewart. In a study published in the American Journal of Preventive Medicine, participants lost 20% of their visceral fat with thrice-weekly sessions that combined 45 minutes of cardio with strength exercises.
At the supermarket: Overall, aim to curb calories, increase fiber, and avoid trans-fats, as all three eating techniques appear to target visceral fat. Or, consider fewer carbs: A study done earlier this year by Stewart and his colleagues found that "combined with exercise, the group eating low-carb lost significantly more belly fat," he says.
At home: Hitting the sack early might also promote visceral fat loss, although Stewart says that more research is needed on the specific connection. Still, aim for at least six hours: One 2010 study, published in the journal Sleep, concluded that individuals who slept less than six hours a night experienced a 32% gain in visceral fat over five years.
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