Reprinted from Eating Disorders Review
March/April 2004 Volume 15, Number 2
©2004 Gürze Books
One of the major challenges of obesity treatment is that most patients regain their weight once treatment ends. About 3 to 5 years after treatment at least 50% of patients are back at their baseline weights. To find ways to prevent this pattern of weight regain, Dr. Suzanne Phelan and researchers at several medical centers studied weight regain and recovery among 2400 people in the National Weight Control Registry (Am J Clin Nutr 2003;78:1079).
The National Weight Control Registry is an ongoing longitudinal study of persons 18 years of age and older who have lost at least 30 lb and kept the weight off for at least 1 year. Participants provide information about their lifetime maximum weight, and current weight and the approximate dates at which they were at these weights.
Dr. Phelan and colleagues found that, on average, the 2400 individuals gained about 3.8 kg between the baseline and two years. Most were above their baseline weight when reassessed at year 2. However, 99.6% of the subjects remained well below their maximum lifetime weight, and 96.4% of the participants remained at least 10% below their maximum lifetime weight.
Of the people who gained weight between the baseline and year 1, only 11% returned to their baseline weights or below at year 2. This represented 7% of the entire sample. Even small amounts of regained weight were rarely lost—of those who gained between 1% and 3% of their initial body weight at year 1, only 17.5% were able to return to their baseline weight or below at year 2. Larger weight gains reduced the chances of recovery even more.
The researchers also found that 25.5% (575) of the participants relapsed, (defined as gaining at least 5% of the lost weight) between the baseline and year 1. Of those, only about 13% re-lost at least half of the weight gained during year 1 gain by year 2. Only 4.7% of the participants returned to their baseline weights at year 1.
Could relapse and recovery be predicted? The only significant predictor of recovery was the amount of weight regained from baseline to year 1. Recovery was also related to a smaller overall increase in depressive symptoms from baseline to year 1.
Still a success
Despite the fact that small weight gains were common and that few persons recovered from even minor lapses, the authors feel the findings should not overshadow the overall success of those in the program. Even though many gained weight over the course of the 2 years, the weight gains were small, such as 3.8 kg. Furthermore, after 2 years, nearly 97% of the sample remained more than 10% below their maximum lifetime weight and the average percentage weight loss from the maximum weight was 26.6%. The authors point out that this very positive result is 2.5 times what is considered successful by current obesity treatment standards.
The strongest predictor of outcome was the amount of weight regained at year 1—those who regained the most weight at year 1 were the least likely to re-lose weight the following year. Identifying ways to prevent minor lapses from turning into relapses should be a focus of future research.
The only other predictor of recovery, according to Dr. Phelan, was smaller increases in depression in the year before weight regain. The authors did not specify whether subjects were enrolled in weight loss programs when they were studied, or had lost the weight on their own.
The clinical implications of these results underscore the importance of helping patients avoid even seemingly small lapses in weight maintenance, even as little as 2 lb, and halting further weight gain. Healthcare professionals may need to encourage patients to react immediately to reverse even seemingly small lapses and, even more important, to identify specific strategies for help patients avoid gaining even small amounts of weight.