Wednesday, July 23, 2003
We've moved the blog. Please join us at our new address.
Thursday, July 03, 2003
An Indictment of Weight Watchers
I recently was having a debate with a former member of the "Show Me the Data" listserv over the relative merits of Weight Watchers. Specifically, is Weight Watchers a positive force for women's health by promoting healthy eating and providing emotional support, or is the overall impact of this massive organization negative?
I argue for the negative case. I will start out with some biomedical issues, but I hope that others here can weigh in on some of the psychological and sociological impact that weight watchers has had on them, on their clients, and on society at large.
1. Weight Watchers does not work. After decades of refusing to publish outcome data, a report has finally appeared (JAMA, April 9 2003 isssue, volume 289:1792-1798). 400 women were randomly assigned to Weight Watchers or to "self-help", which consisted of handing them a brochure. After two years of weekly meetings, weekly weigh-ins and one-on-one consultations the WW group had lost 2.9 kg (6 lbs). They had lost 4.5 kg at the end of the first year but were progressively regaining. Based on the $11 price of the weekly meeting alone, each pound of weight lost cost the experimenters $180.
Most important from my point of view is that there was no fall in risk factors for WW participants. Blood pressure, glucose, insulin, cholesterol and triglycerides were all unchanged despite the weight loss. Contrast this with the fact that all of these risk factors can be improved simply by changing one's diet, even without weight loss. Here, people presumably ate more healthfully, lost wieght, but showed zero improvement in health.
The self-help group is another interesting story. They chose to pursue a number of wieght loss treatments. All of them modified their diets and exercised more. of the 212 participants in this group, 14 took diet pills, 6 took herbal weight loss pills, and 10 joined weight loss clubs including WW while 9 went on low-carbohydrate diets. What was the result of all this effort? Final weight loss at 2 years was one-tenth of one kg or about three ounces.
But this is only part of the story. 29% of the WW participants dropped out despite the free vouchers for all the WW services they wanted. Cleverly, the experimenters used a "last observation carried forward method" for their body weights. What does this mean? This means that if someone dropped out, they were assumed to have maintained 100% of the wieght they had lost up to that point. But it seems more reasonable to assume that if someone was keeping the weight off successfully, they would have kept attending sessions. In fact, it is probably safe to assume that the dropouts regained all the weight they lost. I reanalyzed the data according to this assumption. The final result is an average loss of 2.1 kg or 4.6 pounds. that's an average of less than 5 pounds lost with two years of intensive daily effort and a cost of at least $1,144 not to mention the food scales, books, extra cost of the diet foods etc. All with zero health benefit.
As a final note on the article, it does ackowledge that it was paid for by the WW Foundation, and that WW had a contractual right to review and edit the report. It is also noted in fine print that all the major authors were paid consultants to WW and that the senior author was the head of WW's Advisory Board.
2. Even though the avaerge person does not lose a significant amount of weight in WW, some people do lose weight. Of these people, almost all regain it. This fact can be ascertained by interviewing adult women at random --one in four of all women have been in WW, and nearly every obese woman has. The simple fact that obesity continues to rise rules out the possibility that people are keeping the weight off after WW in any significant numbers.
Weight cycling is a serious issue and WW is probably responsible for more weight lost and regained than any other organization.
3. the WW foundation has been a major force in the support of obesity research. They type of research they have supproted, however, has all been directed to highlighting supposed hazards of obesity, "educating" the public and physicians about the alleged hazards of obesity, and other topics that all tend to reinfirce the recruitment of more clients to WW.
I recently was having a debate with a former member of the "Show Me the Data" listserv over the relative merits of Weight Watchers. Specifically, is Weight Watchers a positive force for women's health by promoting healthy eating and providing emotional support, or is the overall impact of this massive organization negative?
I argue for the negative case. I will start out with some biomedical issues, but I hope that others here can weigh in on some of the psychological and sociological impact that weight watchers has had on them, on their clients, and on society at large.
1. Weight Watchers does not work. After decades of refusing to publish outcome data, a report has finally appeared (JAMA, April 9 2003 isssue, volume 289:1792-1798). 400 women were randomly assigned to Weight Watchers or to "self-help", which consisted of handing them a brochure. After two years of weekly meetings, weekly weigh-ins and one-on-one consultations the WW group had lost 2.9 kg (6 lbs). They had lost 4.5 kg at the end of the first year but were progressively regaining. Based on the $11 price of the weekly meeting alone, each pound of weight lost cost the experimenters $180.
Most important from my point of view is that there was no fall in risk factors for WW participants. Blood pressure, glucose, insulin, cholesterol and triglycerides were all unchanged despite the weight loss. Contrast this with the fact that all of these risk factors can be improved simply by changing one's diet, even without weight loss. Here, people presumably ate more healthfully, lost wieght, but showed zero improvement in health.
The self-help group is another interesting story. They chose to pursue a number of wieght loss treatments. All of them modified their diets and exercised more. of the 212 participants in this group, 14 took diet pills, 6 took herbal weight loss pills, and 10 joined weight loss clubs including WW while 9 went on low-carbohydrate diets. What was the result of all this effort? Final weight loss at 2 years was one-tenth of one kg or about three ounces.
But this is only part of the story. 29% of the WW participants dropped out despite the free vouchers for all the WW services they wanted. Cleverly, the experimenters used a "last observation carried forward method" for their body weights. What does this mean? This means that if someone dropped out, they were assumed to have maintained 100% of the wieght they had lost up to that point. But it seems more reasonable to assume that if someone was keeping the weight off successfully, they would have kept attending sessions. In fact, it is probably safe to assume that the dropouts regained all the weight they lost. I reanalyzed the data according to this assumption. The final result is an average loss of 2.1 kg or 4.6 pounds. that's an average of less than 5 pounds lost with two years of intensive daily effort and a cost of at least $1,144 not to mention the food scales, books, extra cost of the diet foods etc. All with zero health benefit.
As a final note on the article, it does ackowledge that it was paid for by the WW Foundation, and that WW had a contractual right to review and edit the report. It is also noted in fine print that all the major authors were paid consultants to WW and that the senior author was the head of WW's Advisory Board.
2. Even though the avaerge person does not lose a significant amount of weight in WW, some people do lose weight. Of these people, almost all regain it. This fact can be ascertained by interviewing adult women at random --one in four of all women have been in WW, and nearly every obese woman has. The simple fact that obesity continues to rise rules out the possibility that people are keeping the weight off after WW in any significant numbers.
Weight cycling is a serious issue and WW is probably responsible for more weight lost and regained than any other organization.
3. the WW foundation has been a major force in the support of obesity research. They type of research they have supproted, however, has all been directed to highlighting supposed hazards of obesity, "educating" the public and physicians about the alleged hazards of obesity, and other topics that all tend to reinfirce the recruitment of more clients to WW.
Tuesday, July 01, 2003
Just checking in, fist time using a blog! Very much looking forward to the experience. Thanks Tish and Deb for doing this.
Monday, June 30, 2003
Marilyn brought this article to our attention. And Paul Ernsberger shares a story about Peter Herida.
Saturday, June 28, 2003
Yes, welcome! Tish, I appreciate your putting this together for us. I have always wanted to blog but didn't think I could support my own due to time constraints. This is a great solution. I am looking forward to seeing what others will write.
Friday, June 27, 2003
Welcome to the Show Me the Data Blog! Thanks to Tish Parmeley for setting us up and introducing many of us the blogging world.
