A commonly held (although controversial) belief is “once an alcoholic, always an alcoholic”. However, in the area of weight control, people appear to have the opposite impression – that successfully reduced obese individuals should be able to maintain their weight loss “by eating and exercising like normal [weight] individuals.” The proposed research will determine whether successfully reduced obese individuals are able to maintain a normal body weight using behaviors similar to normal weight individuals or whether the reduced obese must work harder to maintain their body weight. This comparison is of interest since both groups have apparently managed to control their body weight despite living in an obesogenic environment. The proposed study compares weight loss maintainers (n=200), defined as individuals who have reduced from overweight/obese to normal weight and maintained the weight loss for a minimum of 5 years, with normal weight controls (n=200) with no history of obesity. The groups will be compared on their eating and exercise behaviors, using tritrac accelerometers and 24 hour recalls to provide a more detailed assessment than used in previous studies of successful weight loss maintainers. We will then compare the groups on the extent to which they have modified their environment to support these behaviors, their preferences for these behaviors, their motivation for maintaining these behaviors, and their quality of life. Findings from this study will have important implications for understanding whether successful weight loss maintainers can at some point regulate their weight in ways similar to normal weight controls or whether they must always work harder to accomplish this. Such information is important for providing an accurate picture to those individuals seeking to lose weight of what it takes to be a successful weight loss maintainer.
A commonly held (although controversial) belief is “once an alcoholic, always an alcoholic”. However, in the area of weight control, people appear to have the opposite impression – that successfully reduced obese individuals should be able to maintain their weight loss “by eating and exercising like normal [weight] individuals”. The purpose of the proposed research is to determine whether successfully reduced obese individuals are able to maintain a normal body weight using behaviors similar to normal weight individuals or whether the reduced obese must work harder to maintain their body weight.
To date, most studies comparing successfully reduced obese and normal weight individuals have examined differences in metabolic rate. While some studies have reported that the reduced obese have a lowered metabolism, which predisposes them to regain,1, 2 other studies have reported no differences.3, 4 Far fewer studies have compared the behaviors of successfully reduced obese and normal weight individuals. The National Weight Control Registry (NWCR) developed by Wing (the PI on this application) and Hill, has provided the most thorough assessment of successful weight losers. The NWCR now includes over 4800 individuals who have lost at least 30 lbs (mean = 60 lb) and kept it off at least 1 year (mean = 6 years). Twelve empirical articles have been published based on the registry documenting the eating and exercise behaviors of registry participants, describing their psychological and metabolic characteristics, and examining maintenance of weight loss over time.
Of particular interest are those participants in the registry who report having kept off the weight for over 5 years. These successful long-term weight loss maintainers report eating a low calorie, low fat diet (similar to others in the registry) and doing high levels of exercise (apparently higher than others in the registry). When followed over time, these individuals have only a .2 relative risk of regaining weight (5 lb or more over one year) compared to members of the registry who lost weight only 1-2 years ago.5 Thus, these individuals could be considered the “gold standard” for weight loss maintenance success. Interestingly, such long duration maintainers report using fewer weight loss maintenance behaviors than short duration weight losers and indicate that less effort (and attention) is required to maintain their weight controlling behaviors.5 These findings raise the question of whether these successful long-term weight loss maintainers resemble normal weight individuals who have no history of obesity, or whether they must continue to practice more extreme behaviors to accomplish their weight loss maintenance. The comparison is of interest since both groups have apparently managed to control their body weight despite living in an obesogenic environment.
We propose to compare successful long-term weight loss maintainers (hereafter referred to as Weight Loss Maintainers) with normal weight Controls and to test the hypothesis that Weight Loss Maintainers must perform more extreme weight controlling behaviors (perhaps due to a biological predisposition to obesity). We will first compare these groups on their actual eating and exercise behaviors using more detailed assessment approaches than previously used in studies of successful weight loss maintainers. We will also compare the groups on the extent to which they have modified their environment to support these behaviors, their preferences for these behaviors, and their motivation for maintaining these behaviors. While we anticipate that Weight Loss Maintainers will exert more effort to control their weight compared to normal weight Controls, we hypothesize that, despite this, their overall quality of life will be better than that of Controls.
a) They practice more weight control behaviors (e.g., pre-planning, stimulus control) and low fat dieting strategies compared to Controls. b) They have simplified/routinized their behavioral choices by decreasing the variety in their diet and maintaining consistency in eating and exercise - even over weekends/holidays.
c) They have arranged their home environment (providing greater availability of healthy foods and activity equipment) and social/work environment (through social and job choices) to support these behaviors.
To test these hypotheses, we propose to recruit 200 individuals who have reduced from overweight/ obese to normal weight, lost at least 10% of their body weight, kept it off at least 5 years, and been weight stable (+ 5 lb.) over the past 2 years. These individuals represent our “gold-standard” successful weight loss maintainers. They will each be asked to identify a normal weight Control of their same age (+ 10 years) and gender. This approach of having “cases” identify controls has been used in prior epidemiological studies to identify controls of a demographic background that is similar to that of the “cases.”6 Weight Loss Maintainers and Controls will be asked to complete assessments of eating, physical activity, and weight controlling strategies using more intensive methodologies than have been incorporated in the NWCR, including Tri-trac accelerometer and random 24 hour recalls. They will also be asked to fill out questionnaires regarding their home and social/work environment, their preference/liking for activity and low fat items, their motivations for food and exercise choices, and their quality of life. Such assessments have not previously been conducted among successful weight losers.
We believe that this study will contribute to our understanding of weight loss maintenance by examining a group of individuals who have clearly maintained their weight loss long-term. By comparing these individuals to normal weight controls, we will be able to determine whether in the long-term, successful weight losers are able to behave like “normal” people or must always continue to “do more” to be successful. The proposed research will help determine how and why successful weight loss maintainers are able to maintain their weight controlling behaviors in the long-term. Such information is important for increasing our understanding of the maintenance process and for providing an accurate picture to those individuals seeking to lose weight of what it takes to be a successful weight loss maintainer.