This news release issued by the Medical University of South Carolina describes results of a multi-center study funded by the Weight Watchers corporation to assess the value of its dietary and communal approach to weight loss in adults with type 2 diabetes.
Over a year’s time, half of the 563 patients with diabetes and obesity or were overweight in this randomized, partially blinded study received standard care including nutrition counseling and written educational materials. The other half were assigned to attend community-based Weight Watchers meetings, had access to the company’s online educational materials, and also had phone consultations and email contact with special diabetes educators who advised them about how to adapt the Weight Watchers meal plans to their diabetes medications and other factors. The results were statistically significant but very modest: both groups lost modest amounts of weight: 4 percent of body weight in the Weight Watchers group and 2 percent of body weight in the standard-of-care group and similarly small increases in the overall rates of long-term blood sugar control. The release would have been improved had it disclosed the numerous ties the lead researchers have with the Weight Watchers corporation and some hard numbers to describe the study’s outcomes and the overall small impact of the Weight Watchers program.
As the release duly notes, obesity and one of its most serious consequences — type 2 diabetes — is a serious and growing public health problem, both in terms of prevention and control. Weight Watchers and other commercial weight loss programs are popular, relatively accessible, but still somewhat costly. In some cases sponsors of weight loss products have made claims of success that were not scientifically demonstrated. Trials published in peer reviewed journals that seek to measure benefits scientifically are welcome but demand scrutiny — particularly those funded by sellers of these weight loss services.
The release notes that there are more than 20 million Americans with type 2 diabetes, but inexplicably says it “can lead to about $85,000 in medical costs,” without noting if that is an average, lifetime, annual or other measure of diabetic — presumably per-person — health care costs. We appreciate the nod to costs but nowhere is there any mention of the cost of Weight Watchers programs. In addition, the release promotes MUSC’s weight management program but does not say whether insurance covers it, or anything about the costs of standard weight management and glycemic control efforts.
The release implies that this program will result in less cost when compared to medical costs of diabetes but that remains unproven.
The release provides minimal quantification of the weight loss results in the two groups of participants:
“After a year, people in the Weight Watchers group had an average weight loss of about 4 percent of their starting weight, compared to 2 percent for the standard care group.”
But we wanted it to go further, especially with respect to outcomes most specific to type 2 diabetes which is the focus of the headline. The release states, “The Weight Watchers group also had a bigger improvement in a measure of long-term control of their blood sugar, which can reduce the risk for serious problems related to Type 2 diabetes.” It would have been helpful had the release told us what measure they are talking about, how much it changed, and provided readers with a target or range of preferred blood sugar levels. We would also liked to have seen weight loss described in actual pounds lost, since that is how most people track their own weight.
In general, the release got the headline right, but overall took far too long to make clear exactly what the end points of the study were (weight loss primarily) and how small — albeit statistically significant — they were.
Most interventions pose some kind of potential harms and Weight Watchers is no exception. For some, particularly those without access to a dedicated dietitian as the study participants had, the amount of sodium in a WW points-based meal plan may be too high, or the vitamins insufficient to maintain nutritional needs.
Although the release provides some information about the participants in the study, it offers no information about their gender, the range of obesity or blood sugar control baselines in the two groups. It does not describe the randomization of the subjects, potentially confounding factors (such as exercise levels) or what medications the participants were taking. It also doesn’t highlight that results may be different for someone embarking on the meal plan on their own without the follow up calls and discussions with dietitians that the study participants had.
No mongering here.
The release makes clear that Weight Watchers funded the study but does not disclose the lead investigators other financial ties to Weight Watchers. The published study states that several of the authors were Weight Watchers employees, held stock in the company, served on its board or were Weight Watchers product patent holders.
The release offers some comparison of the intervention group vs the standard of care group, but does not mention other possible approaches to weight loss such as competing meal replacement plans, liquid supplement diets, exercise-based programs, bariatric surgery and primary prevention in the form of nutritional education among high risk groups.
We already know that intensive interventions for exercise and diet are needed for weight management. It would be useful to know how Weight Watchers compares to these other intensive interventions in terms of cost and effectiveness. In its assessment of a review of comparable meal control programs, the American Academy of Family Physicians found that:
“At 12 months, Weight Watchers participants achieved at least 2.6 percent greater weight loss than the control group, and Jenny Craig users saw at least 4.9 percent greater weight loss than the control group.”
“Other programs, including NutriSystem, showed comparable weight-loss results in the short term, but the study said additional research is needed to determine their long-term results.”
The release notes that because Weight Watchers “has centers all over the country, including sites in small towns with limited or no medical facilities, its program could help meet this need if combined with diabetes-specific counseling.” We’ll give this a marginal satisfactory because while there are, indeed, many Weight Watchers centers, the program will be too costly for many.
The release claims that “The Weight Watchers study is new evidence of what that help might include when it comes to a side effect of weight gain: Type 2 diabetes.” But the research doesn’t appear truly novel. Earlier this year Indiana University publicized its own Weight Watchers-funded study relating to type 2 diabetes, weight loss and glucose control.
The release doesn’t employ sensational language. Those who stick with the release to the end will probably come away with an understanding of the modest benefits of the Weight Watchers program in terms of weight loss and blood sugar control. But some of the language in the lede and early paragraphs of the release are overstated and somewhat misleading.