More than 1/3 of American adults are obese, and more than 8 percent have diabetes, a major cause of heart disease, strokes and kidney failure.
Two studies, released on Monday, compared Type 2 diabetes patients who used medicine alone to those who took medicine and also had stomach-reducing operations. Both studies found that surgery helped far more patients reach normal blood-sugar levels than medicine alone.
The results were dramatic: Some of those who had surgery were able to stop taking insulin as soon as three days after their operations.
Doctors say this is proof that weight-loss surgery should be an early form of treatment for many diabetics. They aren't saying it's a cure because they can't promise that the disease won't come back, but in one study, most surgery patients were able to stop all diabetes drugs and have their disease stay in remission for at least two years.
There were signs that the surgery itself - not just weight loss - helps reverse diabetes. Food makes the gut produce hormones to spur insulin, so trimming away part of it surgically may affect those hormones, doctors believe.
"It's very difficult to lose weight when you're obese or morbidly obese, but if you can lose the weight on your own, then yes, you will probably have just as good of a result as the patients who had weight loss surgery," said Dr. Matthew Lublin, a general surgeon at St. John's Health Center in Santa Monica.
In 2011, because of the rise in Type 2 diabetes, the government lowered weight requirements for Lap-Band surgeries, a less risky form of weight-loss surgery. The surgery done in the study was the more invasive gastric bypass and sleeve.
"When somebody is thinking about weight-loss surgery, you have to weigh the benefits of the surgery versus the risks," Lublin said. "You have to come to your own conclusion of which operation you feel safer and better having."
The studies were published online by the New England Journal of Medicine, and the larger one was presented Monday at an American College of Cardiology conference in Chicago.
Lublin noted that the New England Journal of Medicine study was only a year long, so the new research can't definitively say whether the diabetes control is temporary or long-term.