The commercial weight loss industry has grown by leaps and bounds as more and more Americans seek to drop the pounds in any way they can. Today, the industry is worth about $2.5 billion. But, according to a new study, many of these programs are actually backed by any scientifically sound studies.
The report, published in the Annals of Internal Medicine, found among 32 popular commercial weight loss programs available, only 11 have been studied using a randomized controlled trial. Of these 11 that have been studies, only 2 - Weight Watchers and Jenny Craig - indicated that people who used the programs lost more weight after 12 months than people who follow their own diet.
"Losing weight and keeping it off is a top concern for most Americans," lead study author Kimberly Gudzune, assistant medicine professor at Johns Hopkins University, said. "I'm a physician myself, so I thought it was really important to give patients and their physicians guidance on programs to show which can really help them lose weight."
No federal legislation requires commercial weight loss companies to provide scientific evidence that their programs work, but the Federal Trade Commission (FTC) recommended in 1999 that these companies conduct studies to do so. One reason for a lack of study and regulation, Gudzune says, is up until late 2013, the American Medical Association hadn't even treated obesity as a medical condition.
"It was viewed as an individual problem and an issue of willpower and over the past 10 to 20 years, we've learned so much about the factors not just on a personal level, but that the environment and physiologic factors can contribute to this picture. It's more complicated than we thought."
Christine Santori, a registered dietician and program manager for the Center for Weight Management at North Shore-LIJ Syosset Hospital, in Syosset, New York, said that the attrition rates are what stand in the way of good research into the programs.
"Most of our patients come in with a long list of prior weight loss attempts, unsuccessful in most of them," Santori, who was not involved in the Johns Hopkins study, said. "What I hear over and over again, is, 'I don't know how to do it.' Most of the time it's about behavioral strategies and the changes they should be making. It's a lot of program solving. It's setting them up for long-term success."
Weight Watchers and Jenny Craig were the only two diet programs that have been studied with a controlled trial that showed participants lost weight over one year, the losses were modest at best. In one year, people on Jenny Craig lost an average of 15 pounds, while people on Weight Watchers lost an average of 12 pounds.
"Both seem small and I think would be surprising to many patients- those usually translate into a 3 to 5 percent weight loss for the starting weight for most of the patients in these trials," Gudzune says.
Mitchell S. Roslin, chief of obesity surgery at Lenox Hill Hospital in New York City, who wasn't involved in the research, said he wasn't surprised by the study's findings.
"I think that the bottom line is commercial diets may work for people who are health conscious, but they're not going to work for people who are less health conscious and need it the most," Roslin says. "We keep on missing the big point."
