Nearly half of participants in weight-loss programs drop out before completing them, according to a new study.
The researchers found that 43 percent of participants in one weight-loss program - including some who underwent bariatric surgery - dropped out of the program before dropping the desired pounds.
Among participants who had undergone the surgery, the drop-out rate was 12 percent, while the rate was 54 percent among those who had not undergone the surgery.
These drop-out rates are in line with those seen in other studies, and they are a barrier to reducing obesity rates, the researchers said.
The big difference between the drop-out rates of those who underwent surgery and those who didn't may yield clues to what motivates people to stay in their programs, the researchers said.
"We speculate that patients willing to undergo the initial bariatric surgical procedure may be more committed to complete the program," they wrote. But they also said that the immediate weight loss that comes with having surgery could motivate people to continue.
The researchers studied 1,205 participants in the program, 318 of whom had weight-loss surgery. The program lasted at least a year, though it was extended to at least two years for bariatric patients. The program included general health advice on topics such as mental health and quitting smoking because other health problems, such as depression, can affect weight.
The drop-out rates are disappointing but not remarkable, said Susan Jebb, who leads diet and population health research at the Medical Research Council in Cambridge, England. Jebb was not involved in the study.
People drop out of weight-loss programs when they feel they've benefited all they can from them, Jebb said. It's very easy for participants to assess whether they're still losing weight.
People were perhaps less likely to drop out after having surgery because surgery adds medical significance to weight-loss efforts, and could make people more willing to continue consulting a doctor, she said.
The findings suggests that a major way to combat the obesity epidemic, which affects more than 1.7 billion people worldwide, could be to improve the retention rates of weight-loss programs, the researchers said.
In order to be successful, weight-loss programs need to be intensive and specific, and participants need to be willing to dramatically change their lifestyles, said Dr. Jim Early, a professor at the University of Kansas medical school in Wichita.
"We live in a society that gives us a huge opportunity to eat low-cost calories," Early said, noting he was also unsurprised by the drop-out rate. "People don't want to give up their comfort foods."
The study was published Aug. 1 in the Canadian Journal of Surgery.