A one-year weight loss program based on lifestyle changes can help obese people shed almost as many pounds as surgery, German researchers say.
In a study published in the International Journal of Obesity, they found women who stuck with the program lost 43 pounds, while men trimmed their weight by 57 pounds.
But more than 40 percent quit before the year was up. And even among completers, three-quarters of the weight they'd lost had crept back after three years.
"Weight regain remains the Achilles' heel of all weight loss therapies," said Thomas Wadden, who runs the Center for Weight and Eating Disorders at the University of Pennsylvania in Philadelphia and was not involved in the new work.
Excess weight is one of the world's greatest health problems, tied to a host of chronic diseases, extra health care spending and early death. In the U.S., about a third of adults are obese.
While weight loss surgery effectively helps people slim down, complications and cost make the procedure less than ideal.
In the new study, Stephan Bischoff of the University of Hohenheim in Stuttgart and colleagues used a number of lifestyle changes, including a low-calorie diet, behavioral therapy, group meetings, nutritional counseling and exercise -- a weight loss program franchised by Nestle as OPTIFAST52. There is also an OPTIFAST program in the US, but it is only half as long as the German program.
The researchers, all of whom work for OPTIFAST centers, signed up more than 8,000 obese participants at dozens of centers across the country.
At the start of the program, women weighed about 247 pounds on average and men weighed 301 pounds. Combining all participants regardless of whether or not they finished the program, women lost an average of 33 pounds, with men shedding about 10 pounds more.
Those who stuck it out, about six out of every ten participants, lost 53 percent of their excess weight. That's close to the weight loss achieved by surgery -- about 60 percent -- the researchers note.
Completers also saw a number of other positive effects, such as lower blood pressure, lower cholesterol and blood sugar levels and better quality of life.
But when the researchers tracked a sample of 300 people three years after they'd completed the program, it turned out they had regained most of their original poundage. According to experts, that's less likely to happen after surgery.
Still, Bischoff said, a fifth of the participants were able to keep their new weight without further help.
Potential side effects from the program were rare, with the most common ones -- hair loss and constipation -- reported by less than one percent of the participants.
Whether those problems are a real consequence of the Nestle program is still uncertain, because the study didn't include a control group. By the same token, it's hard to be sure exactly what benefits came from the program itself, as opposed to just being part of a scientific study.
And there are other problems with the program, said Stanley Heshka, a nutrition researcher at Columbia University in New York.
Although OPTIFAST52 appears to work in the short term, he told Reuters Health by email, it is not a practical solution to America's obesity problem. Obese Americans tend to be poor, while intensive programs like Nestle's tend to be "very costly."
University of Pennsylvania's Wadden does see promise in weight loss programs, but said they need to do a better job of helping participants keep the pounds off.
"For every month that you spend losing weight, you should spend another month learning how to keep the weight off," he said.