Diet and exercise success rates?

[ouroborous 519]

Hi, I've heard quoted a few times now, from different sources, that "only five percent of obese people are able to lose weight and keep it off with diet and exercise alone."

Of course, this is a great -- perhaps the strongest -- motivation for seeking weight loss surgery. But, is it true?

So, in the spirit of being scientific, I'd like to ask if anyone has ever seen a study corroborating the five percent figure. Obviously, if the number is 80% instead of 5%, that's going to significantly change how I think about WLS.

To be specific, I'm only interested in peer-reviewed research here.

[ouroborous 519]

Here's one study showing "greater than 20%" able to lose 10% of their body weight and keep it off for one year or more.

SUCCESSFUL WEIGHT LOSS MAINTENANCE - Annual Review of Nutrition, 21(1):323 - Abstract

I'm really curious where the 5% figure comes from.

[Tiffykins 672]

Here is a study out of UCLA:

http://mann.bol.ucla.edu/files/Diets_don%27t_work.pdf

It's a huge article (14 pages) on clinical studies of diet and exercise programs/intervention and the results are that most people gain all their lost weight back and then some.

[ouroborous 519]

This isn't about success rates, but interestingly one WLS (RnX) showed a greater positive effect than diet and exercise:

A comparison of diet and exercise therapy versus laparoscopic Roux-en-Y gastric bypass surgery for morbid obesity: a decision analysis model*1

Journal of the American College of Surgeons, Volume 196, Issue 3, March 2003, Pages 379-384

Emma J. Patterson MD, FRCSC, David R. Urbach MD, MSc, FRCSC, and Lee L. Swanstr?m MD, FACS.

Abstract:

BackgroundIn the absence of randomized controlled trials that directly compare medical versus surgical treatment of morbid obesity, decision analysis is a useful tool to help determine the optimal treatment strategy. Using decision analysis we simulated a trial comparing diet and exercise therapy to laparoscopic gastric bypass surgery to determine which approach resulted in longer life expectancy.Study designA Markov decision analysis model was constructed to evaluate survival after laparoscopic Roux-en-Y gastric bypass surgery compared with a diet and exercise program for a 45-year-old woman with a body mass index (BMI) of 40 kg/m2. Baseline mortality data were derived from published tables of vital statistics, and the relative risks of death associated with obesity (relative to normal weight) were taken from epidemiologic studies. We assumed that successful surgery resulted in a reduction of BMI to 30 kg/m2. The baseline assumptions were: an operative mortality of 0.4%; a probability of weight loss after surgery of 80%; a rate of weight loss on a diet and exercise program, 20% at two years; a rate of regain of lost weight, 95% at two years; a relative risk of death for a BMI of 40 kg/m2, 2.70; and a relative risk of death for a BMI of 30 kg/m2, 1.51.ResultsThe undiscounted life expectancy after surgery was 69.7 years compared with 67.3 years for a diet and exercise program (an absolute increase in life expectancy of 2.4 years, a relative increase in life expectancy of 10.8%). Sensitivity analyses assumed discounting at 5%/y, and showed that surgery was associated with a longer expectation of life when the risk of operative mortality was less than 10%, and when the probability of weight loss after surgery was greater than 4%.ConclusionsIn a decision analysis model, laparoscopic gastric bypass surgery for morbid obesity was associated with a substantially longer survival than diet and exercise therapy.

[thinoneday 445]

Yahoo for Tiffy! Loved your article! Glad you had a blast in Dallas, sounded like fun! Was Easter good for you? Mine was great!

[ouroborous 519]

Here is a study out of UCLA:

http://mann.bol.ucla.edu/files/Diets_don%27t_work.pdf

It's a huge article (14 pages) on clinical studies of diet and exercise programs/intervention and the results are that most people gain all their lost weight back and then some.

Thanks for that, I'll take a peek at it.

[Tiffykins 672]

Yahoo for Tiffy! Loved your article! Glad you had a blast in Dallas, sounded like fun! Was Easter good for you? Mine was great!

We were on the road for 12 hours all day yesterday. It was a blast because the kiddo and me really know how to roadtrip. We missed traditional Easter celebration, but vacation was great.