WEDNESDAY, June 4, 2014 (HealthDay News) -- Compared to diet and lifestyle changes, gastric bypass surgery appears to be the clear winner in helping obese people with type 2 diabetes lose weight and even rid themselves of the disease, new studies show.

The findings "further confirm that gastric bypass is the most effective way of treating type 2 diabetes in obese patients, and that surgery is superior to medical treatment for the disease in terms of blood sugar control," said Dr. Subhash Kini, a bariatric surgeon and associate professor of surgery at the Icahn School of Medicine and The Mount Sinai Hospital, in New York City. He was not involved in the two new studies.

The findings were published June 4 in JAMA Surgery.

As obesity rates in the United States continue to rise, so do rates of obesity-linked type 2 diabetes. For years, improved diet, lifestyle changes and certain weight-loss medications were thought to be the only way to help obese diabetics slim down. However, the advent of weight-loss surgeries such as gastric bypass and the gastric banding procedure have brought new treatments to the fore.

In one of the new studies, researchers led by Dr. Anita Courcoulas, of the University of Pittsburgh Medical Center, tracked outcomes for 69 obese or very obese patients who were assigned to receive either gastric bypass, gastric banding, or a traditional lifestyle-change intervention.

They report that people who underwent gastric bypass had an average 27 percent drop in their weight, compared to a 17.3 percent weight loss for those who got gastric banding, and about a 10 percent loss for those who tried diet/exercise changes.

The results were similar when it came to diabetes: One year after the intervention, 50 percent of the gastric bypass patients saw their type 2 diabetes partially ease and 17 percent saw it completely disappear, compared to 27 percent and 23 percent, respectively, for those who got the banding treatment.

None of the patients on the lifestyle-change regimen saw any remission of their diabetes, the study authors noted.

In the second study, a team led by Dr. Florencia Halperin of Brigham and Women's Hospital in Boston tracked the one-year outcomes of 38 obese or very obese people with type 2 diabetes. The patients underwent either gastric bypass or drug/lifestyle weight-management interventions.

Again, the surgery seemed to produce the best results, according to the study. Fifty-eight percent of people in the gastric bypass group saw their type 2 diabetes go into remission within a year after the procedure, compared to just 16 percent of those who got the lifestyle intervention.

People who got the surgery also saw improvements in weight, waist circumference, blood pressure and blood cholesterol levels, the Boston researchers said.

Both studies were funded in part by the U.S. National Institutes of Health.

Halperin's team stressed, however, that a much larger clinical trial is needed -- something that might be difficult to put together.

Kini agreed. He said there are "potential challenges to successfully completing a larger randomized, controlled trial for treatment of type 2 diabetes and obesity in obese patients." Both of the new studies had only a small number of people enrolled, Kini noted.

Dr. Mitchell Roslin is chief of bariatric surgery at Northern Westchester Hospital in Mount Kisco, N.Y. He said that "the data is clear -- the treatment of choice for type 2 diabetes and morbid [severe] obesity is a gastric bypass procedure."

Roslin believes that the time has come for insurance companies and other third-party payers to help cover the cost of these procedures for obese type 2 diabetics.

"Why, with data this clear, are only a minority of patients with diabetes and other metabolic diseases secondary to obesity having these lifesaving procedures?" he asked. "Until there are better medical remedies, obese type 2 diabetics should be treated with gastric bypass procedures."

More information

For more on bariatric surgeries and type 2 diabetes, head to the American Diabetes Association.