To investigate weight loss expectations and goals among obese treatment seekers and to examine the relationships of these expectations and goals to treatment outcomes.
Participants were 180 obese men and women (age 43.8±10.1 years; body mass index 37.6±4.2 kg/m2) who received one of four-year-long treatments that combined behavioral and pharmacological methods. Before treatment, they reported the amount of weight they realistically expected to lose after 4, 12, 26 and 52 weeks of treatment, as well as their ultimate weight loss goals. Expectations and goals were compared across treatment groups and examined in relation to previous weight loss efforts, weight loss and regain in treatment, attrition, satisfaction with treatment and mood.
Participants in all treatment groups expected reductions at week 52 that were significantly greater than the 5–15% of initial weight they were told was realistic and significantly more than they had ever lost before. Weight loss expectations were unrelated to achieved weight loss in all groups but one, in which greater expectations were associated with greater losses. Failure to meet weight loss expectations for the first 26 weeks of treatment was related to lower satisfaction ratings, but was not related to weight regain or attrition over the next 26 weeks. Symptoms of depression were reduced from baseline, regardless of whether participants achieved or failed to achieve their expected weight losses.
Across groups, we observed no negative consequences of having (and failing to meet) unrealistic expectations for weight loss.
Numerous studies have shown that obese individuals want to lose the equivalent of 25–35% of their initial weight and expect to do so in approximately 1 year of treatment.1, 2, 3, 4 Dieters maintain these expectations even when repeatedly informed that they are likely to lose only 5–15% of initial weight,5 which is the size of the losses typically induced by current behavioral and pharmacological interventions.6
Investigators disagree concerning the consequences of patients' unrealistic goals and expectations. Some believe that weight regain is, in large part, attributable to patients' disappointment with failure to reach their goals, which leads patients to abandon efforts to maintain the modest weight losses that they did achieve.7, 8 In support of this hypothesis, Dalle Grave and colleagues3, 9 found that greater weight loss goals and expectations were associated with earlier attrition from therapy and smaller reductions in body mass index (BMI) after 1 year of treatment. Other investigators, however, have failed to observe adverse effects of large weight loss goals. Such goals were either unrelated to weight loss5, 10, 11, 12 or were associated with slightly greater losses.4 In contrast to Dalle Grave et al.,9 Foster et al.1 found no relationship between weight loss goals and attrition from treatment.
Prior studies of weight loss goals have had several limitations including small sample sizes,1, 5, 13 as well as the provision of relatively brief therapies,4, 12 only one type of therapy,1, 10 or unspecified therapies.3, 9 It is possible that the importance of goals and expectations differs across treatment approaches. In addition, most studies have focused only on how much weight patients ultimately wanted to lose (that is, weight loss goals) rather than on how much weight they realistically expected to lose during a given time with a specific treatment (that is, weight loss expectations). Patients' failure to meet treatment expectations, which they perceive as realistic, may be more detrimental to long-term success than failure to reach ‘ultimate’ or ‘dream’ weight loss goals, which dieters may know they have a slim chance of achieving.
The present study evaluated long-term weight loss goals, as well as specific expectations to be achieved in 1 year of treatment, in obese individuals who received one of four interventions that combined lifestyle modification and pharmacotherapy. Based on prior results, we anticipated that all four groups would have unrealistic expectations for weight loss. Consistent with theory,7, 8 we predicted that persons who failed to meet their expectations for weight loss at week 26 would have greater attrition and poorer maintenance of weight loss at week 52. Furthermore, we predicted that failure to meet weight loss expectations at week 26 would be related to an increase in psychosocial distress. This study also provided the opportunity to examine whether expectations were related to previous weight loss experiences and whether expectations varied by type of therapy received.
Participants were 149 women and 31 men with a mean (±s. d.) age of 43.8±10.1 years, weight of 106.1±17.1 kg, height of 167.7±8.5 cm and BMI of 37.6±4.2 kg/m2. Over two-thirds (67.6%) of the sample was Caucasian, and 57.5% had at least 16 years of formal education. All participants were enrolled in a randomized controlled trial that combined behavioral and pharmacological interventions for weight loss and has been described previously.14 Although the larger trial included 224 individuals, the present sample included only 180 participants who completed questionnaires regarding their weight loss expectations and goals before treatment. Excluded participants did not differ from included participants with respect to gender, age, weight, height, BMI, ethnicity or education, but had a higher rate of attrition at 1 year (29.5 vs 14.4%, respectively).
Both before and after randomization to treatment groups, participants completed a paper-and-pencil questionnaire that assessed weight loss expectations, goals and experiences.5 Thus, they completed the questionnaire once when they had only limited information about treatment (i.e., at a screening visit), and then a second time after they had been fully informed of the treatment options and had been assigned to one of four treatment groups (that is, at baseline). After 26 weeks of treatment, participants completed a similar questionnaire that also inquired about satisfaction with weight loss and its perceived effects, as well as their motivation for continued weight loss.
Participants were randomly assigned to one of four treatment conditions, as noted above.14 All participants were instructed to consume 1200–1500 kcal per day and to walk 30 min a day on most days of the week. Those in the ‘sibutramine alone’ group (n=44) had eight visits of 10–15 min with a primary care provider and received a pamphlet that provided tips for healthy eating and activity. They also were prescribed sibutramine (Abbott Laboratories Inc., Abbott Park, IL, USA), a serotonin-noradrenaline reuptake inhibitor that is indicated for the induction and maintenance of weight loss. Medication was begun at 5 mg and titrated to 10 and 15 mg at weeks 3 and 6, respectively. Participants randomized to the lifestyle modification alone group (n=42) attended weekly group meetings for 18 weeks, bi-weekly meetings through week 40 and a follow-up visit at week 52. Treatment included keeping daily records of energy intake and expenditure and followed the LEARN Program for Weight Control15 and the Weight Maintenance Survival Guide.16 Participants who received combined therapy (n=49) received both treatments described above (with the LEARN Program adapted for use with sibutramine17). Thus, they received both medication and the group program of lifestyle modification. Participants in the sibutramine plus brief therapy group (n=45) received the same medication regimen as those in the sibutramine alone group and the same written materials as those in the combined therapy group. The material, however, was covered during eight brief visits with a primary care provider, rather than in the group sessions described above. All participants gave their written informed consent to participate in the study, which was approved by the institutional review board of the University of Pennsylvania.
Weight was measured at baseline and at all treatment visits with participants dressed in light clothing. Weight changes were calculated in kilograms and as percentage of initial weight lost.
Weight loss expectations and goals
At both screening and baseline visits, participants completed a questionnaire that asked their expectations and goals for weight loss. Specifically, they were asked ‘How much weight do you expect to lose after the first [4, 12, 26 and 52] weeks of the program?’ Participants also answered, ‘How much weight would you like to lose in total, whether or not you think you can achieve this loss… Another way of asking this question is ‘what is your ultimate weight loss goal?’’ These questions were used in a previous study.5.
Weight loss experiences
Participants indicated at baseline how much weight they typically lost ‘when you reduce on your own, without joining a weight loss program or getting help from your doctor?’ as well as ‘when you participate in a formal weight loss program (i.e., Weight Watchers, Optifast, weight loss medication, and so on)?’ Participants also reported their largest weight loss ever.
Satisfaction and motivation
At week 26, participants rated their satisfaction (1=‘very dissatisfied’ to 9=‘very satisfied’) with the changes in weight, appearance, physical health and energy, and self-esteem that they achieved at that point. They also rated their motivation (1=‘not at all motivated’ to 10=‘extremely motivated’) to continue to lose weight.
Participants completed the Beck Depression Inventory (BDI), second edition18 at baseline and at week 52. Higher scores indicate greater symptoms of depression.
Paired t-tests were used to compare within-subject differences in continuous variables. Univariate and multivariate analyses of variance (ANOVAs and MANOVAs, respectively) were used to assess between-groups differences in continuous variables. Post hoc analyses, when appropriate, were conducted using Tukey's Honestly Significant Difference test. Relationships among continuous variables were tested using Pearson's correlations, controlling for relevant characteristics. The χ2 test was used to determine differences in attrition between participants who did and did not achieve their expected weight losses at week 26.
Initial expectations and goals
Before randomization, participants reported that they expected to lose 4.0±1.5 kg after 4 weeks, 8.5±3.2 kg after 12 weeks, 14.5±5.3 kg after 26 weeks and 22.2±8.5 kg after 52 weeks of treatment. The corresponding reductions in initial weight were 3.8±1.3, 8.1±3.0, 13.7±4.6 and 20.9±7.1%, respectively. Participants' ultimate weight loss goals, regardless of whether they thought they could achieve them during the program, were 32.9±14.0 kg, equal to a 30.6±10.5% reduction in initial weight.
Changes in expectations and goals following assignment to groups
Paired t-tests revealed that participants had significantly smaller expectations for weight loss at week 52 (P=0.001) after being informed that they could expect to lose 5–15% of their weight (approximately 6–16 kg for this sample) and being assigned to treatment groups (see Table 1). Still, the expected loss at week 52 was nearly 15 kg greater than the reductions participants typically achieved when they lost weight on their own, 8.5 kg greater than what they typically achieved in formal weight loss programs and 1.5 kg greater than their most successful previous attempts (see Figure 1). Additionally, a one-sample t-test showed that participants' expected reductions at week 52 were significantly greater than the 15% reduction in initial weight they were informed they could realistically achieve with the interventions offered (P<0.001).
Differences among groups in expectations and goals
A MANOVA found no significant differences among the four treatment groups in participants' expected weight losses (assessed at baseline) for weeks 4, 12, 26 or 52, or in their ultimate weight loss goals. Similarly, there were no significant differences among the four conditions in changes, from the screening to the baseline assessments, in participants' expectations or goals for weight loss.
Baseline characteristics associated with expectations and goals
As shown in Table 2, gender, ethnicity, age and baseline BMI were significantly related to weight loss expectations and ultimate weight loss goals (assessed at baseline and calculated as percentage of baseline weight). A MANOVA revealed that women expected significantly greater reductions than men at weeks 26 and 52 and had greater ultimate weight loss goals (all Ps<0.01). Post hoc tests following a separate MANOVA found that Hispanic participants (n=7) expected significantly larger losses than African Americans (n=49) at weeks 4, 12, 26 and 52 and desired greater total weight losses (P=0.01–0.05). Hispanic participants also expected significantly larger reductions than Caucasians (n=121) at week 52 (P=0.02). African Americans and Caucasians did not differ significantly in their ultimate weight loss goals or in any of their expected losses over the year.
Pearson's correlations found that age was significantly and negatively related to expectations for weight loss at weeks 26 (r=−0.15, P=0.04) and 52 (r=−0.22, P<0.01), as well as to ultimate weight loss goals (r=−0.17, P=0.03). BMI was significantly and positively related to expected loss at week 52 (r=0.15, P=0.04) and ultimate weight loss goals (r=0.36, P<0.001). Thus, younger participants and more obese individuals expected and desired greater reductions.
Expected vs achieved weight reductions
Measured weights were available for 152 and 154 participants at weeks 26 and 52, respectively. A MANOVA with subsequent post hoc tests revealed greater weight losses in the combined therapy group than all other groups at week 26 (all P<0.03). Combined therapy was superior to sibutramine alone and lifestyle modification alone (P<0.01), but equivalent to sibutramine plus brief therapy, at week 52 (see Table 3).
Across all groups, participants' weight losses at week 26 were significantly smaller than those they had expected to achieve at this time (11.1±6.2 vs 13.2±5.3%, respectively, Ps<0.001), as was the case at week 52 (9.2±8.1 vs 19.0±7.3%, respectively, P<0.001). On average, participants achieved 91.0±63.6% of their expected weight loss at week 26 but only 50.1±49.5% of their expected loss at week 52. More than one-third (36.0%) of participants achieved or exceeded their expected loss at week 26 but only 13.4% did so at week 52.
Partial correlations, controlling for treatment condition and baseline BMI, showed a small but statistically significant relationship between the amount of weight participants expected to lose at week 26 and the amount they actually lost at that time (r=0.17, P=0.04). Expected and achieved weight losses at week 52 were not related in the full sample. Correlations between expected and achieved reductions, controlling for baseline BMI also were examined separately within each treatment group. Expected weight losses were not associated with achieved reductions at weeks 26 or 52 for participants in the sibutramine alone, lifestyle modification alone or combined therapy groups (r ranged from −0.07 to 0.23). Among participants who received sibutramine plus brief therapy, however, expectations were positively related to achieved weight losses at week 26 (r=0.49, P=0.004) and week 52 (r=0.39, P=0.03). Thus, participants who were treated with sibutramine plus brief therapy and expected greater weight losses achieved greater reductions at both assessment points.
Ultimate goals vs achieved reductions
Only 3.9 and 5.0% of participants met or exceeded their ultimate weight loss goals at weeks 26 and 52, respectively. Partial correlations between participants' ultimate weight loss goals and achieved reductions at weeks 26 and 52 were not statistically significant when examining the four treatment groups together (controlling for treatment group and baseline BMI) or when assessing each group separately (controlling for baseline BMI). Correlation coefficients ranged from −0.16 to 0.26.
Weight-related consequences of unmet expectations
The mean weight change from weeks 26 to 52 was +1.6±4. 6 kg (equal to 1.6±4.4% of initial weight), ranging from losing an additional 11.6 kg to gaining 27.2 kg. An ANOVA found that weight regain did not differ significantly between those who achieved (+0.7±6.2 kg) and those who failed to achieve (+2.2±3.2 kg) their expected weight losses at week 26. There also was no main effect of treatment group on weight regain and no interaction between treatment group and achieving (or not achieving) week 26 weight loss expectations. When controlling for weight loss at week 26, there was no significant correlation between the extent to which participants met their expectations for weight loss at week 26 (that is, the percentage of their expected reductions that they actually achieved) and their weight change from weeks 26 to 52 (r=−0.06).
A χ2 test showed persons who failed to achieve their expected reductions by week 26 were no more likely to drop out by week 52 than were those who met or exceeded their expectations for weight loss at week 26. Attrition in these two groups was 6.5 and 3.4%, respectively. Examined differently (with ANOVA), participants who completed week 52 did not differ significantly from dropouts with respect to the amount of weight they lost at week 26 (11.2±6.1 vs 9.4±8.0%, respectively) or the percentage of their expected weight loss they achieved at week 26 (95.5±63.5 vs 70.8±77.0%, respectively).
Psychosocial consequences of unfulfilled expectations
As shown in Figure 2, a MANOVA found that participants who failed to meet their expectations for weight loss at week 26 were significantly less satisfied with their weight losses and associated changes than were those who met or exceeded their expectations at that time (P<0.001). Correlation analyses showed significant positive relationships between the extent to which participants met their expectations for weight loss at week 26 and their satisfaction (r ranged from 0.43 to 0.51). The extent to which participants met expectations at week 26, however, was not significantly correlated with their motivation to continue to lose weight (r=0.08). Nor was there a statistically significant difference in motivation between participants who did and did not meet their expectations at week 26, as determined by ANOVA (8.4±2.1 vs 8.0±1.8, respectively).
Examining the four treatment groups together, a paired t-test found that participants' mean baseline BDI score of 7.6±7.1 fell significantly to 5.8±9.4 at week 52 (P=0.02). An ANOVA found no main effect of treatment group or of achieving (or not achieving) weight loss expectations on BDI scores at week 52. There also was no significant interaction between treatment group and achieving weight loss expectations at week 52. Although there was a statistically significant correlation between the extent to which participants achieved their expectations for weight loss at week 52 and their BDI scores at that time (r=−0.27), this relationship was not significant after controlling for baseline BDI scores (r=−0.17).
The principal finding of the present study was that failure to meet short-term weight loss expectations was not associated with poorer long-term outcomes. Participants who failed to achieve their expected weight losses at week 26 were no more likely to drop out or to regain more weight over the next 6 months than were those who met or exceeded their expected losses at week 26. In addition, BDI scores at week 52 were significantly reduced from baseline values and were not related to meeting (or failing to meet) weight loss expectations at that time. Thus, persons who did not meet their expectations had equivalent outcomes as compared with those who met or exceeded their expectations for weight loss. These findings were materially unchanged when the extent to which participants met their weight loss expectations was examined as a continuous variable.
Consistent with previous research, this investigation found that participants expected to lose significantly more weight than was realistic for the treatment provided, and ultimately desired to lose about one-third of their initial weight.1, 2, 3, 4, 5 The losses they expected after 1 year of behavioral and/or pharmacological treatment were nearly four times what they typically achieved when they lost weight on their own and approximately double what they typically achieved in formal weight loss programs. In addition, participants expected a nearly constant rate of weight loss over 12 months, apparently unaware of the plateau that typically occurs after 4–6 months of treatment.19, 20
There was a small positive relationship between participants' expected and achieved weight losses at week 26. Thus, participants with higher expectations lost more weight in the first 6 months of treatment. The association observed in the full sample appeared to be attributable to the positive relationship found among participants in the sibutramine plus brief therapy condition. We cannot explain why greater expectations would be related to greater reductions in that treatment group but not the others.
Overall, the associations found in the present study contrast with the findings of Dalle Grave and colleagues,3, 9 who reported smaller reductions and greater attrition among persons with greater expectations for weight loss. The difference in findings may be attributable, in part, to methodological differences. For instance, the methods used to assess weight loss expectations and goals varied across studies. Additionally, participants in the Dalle Grave studies sought treatment in medical centers and presumably had to pay for services. Thus, they would have a financial incentive to discontinue treatment if they found its results to be unsatisfactory. In the present study, there was no disincentive to remain in treatment because services were provided at no cost to participants. Our findings, however, are consistent with the results of several other clinical trials, which found modest positive, if any, relationships between participants' expected and achieved weight losses4, 5, 10 and no relationship between failure to meet expectations and attrition.1
This study found that the intensity of the therapy provided did not appear to influence weight loss expectations or goals to a significant degree. Participants appeared to come to treatment with predetermined expectations and goals, which they did not modify in response to being assigned to different therapies or told to expect a loss of only 5–15% of initial weight.
As shown in previous studies,2, 3 we found that women, younger participants and those with a higher BMI expected and desired greater reductions. The finding that Hispanic participants had greater weight loss expectations and goals was surprising. Previous research on body image and cultural norms suggests that Caucasians would be expected to have the greatest, and African-Americans the lowest, expectations and goals for weight loss.21 No differences, however, were found between those groups. The small number of Hispanic participants in the present study limits our confidence in the observed ethnic differences.
Is it time to shift research and clinical attention away from expectations and goals for weight loss? Despite expecting and desiring reductions much larger than the 10% initial target recommended by the National Heart, Lung, and Blood Institute's expert panel,22 obese individuals do not appear to be dissatisfied with the modest reductions they achieve, as found in the present study and in other investigations.1, 5 Furthermore, several studies have now found expectations to be not only difficult to alter, but also of limited clinical importance. Wadden et al.5 found that informing participants, both verbally and in writing, of the weight losses they could realistically expect to achieve with pharmacological and behavioral treatment resulted in significantly smaller, but still unrealistic, expectations. Foster et al.13 and Ames et al.11 tested more comprehensive cognitive-behavioral programs and found that these treatments were effective for reducing weight loss expectations but not for improving weight loss or maintenance.
The theory that unmet expectations lead to disappointment and discontinuation of weight control efforts makes intuitive sense but has received limited empirical support. Unfortunately, weight regain is common in controlled trials and is likely even more widespread in uncontrolled self-directed weight loss efforts. Regain is likely attributable to a complex interaction of behavioral, environmental, neuroendocrine and cognitive factors.23 Neither unrealistic expectations nor goals, in isolation, appear to be the culprit.
Foster GD, Wadden TA, Vogt RA, Brewer G . What is a reasonable weight loss? Patients' expectations and evaluations of obesity treatment outcomes. J Consult Clin Psychol 1997; 65: 79–85.
Foster GD, Wadden TA, Phelan S, Sarwer DB, Sanderson RS . Obese patients' perceptions of treatment outcomes and the factors that influence them. Arch Intern Med 2001; 161: 2133–2139.
Dalle Grave R, Calugi S, Magri F, Cuzzolaro M, Dall'Agio E, Lucchin L et al. Weight loss expectations in obese patients seeking treatment at medical centers. Obes Res 2004; 12: 2005–2012.
Linde JA, Jeffery RW, Finch EA, Ng DM, Rothman AJ . Are unrealistic weight loss goals associated with outcomes for overweight women? Obes Res 2004; 12: 569–576.
Wadden TA, Womble LG, Sarwer DB, Berkowitz RI, Clark VL, Foster GD . Great expectations: ‘I'm losing 25% of my weight no matter what you say’. J Consult Clin Psychol 2003; 71: 1084–1089.
Fabricatore AN, Wadden TA . Obesity. Annu Rev Clin Psychol 2006; 2: 357–377.
Cooper Z, Fairburn CG . A new cognitive-behavioral approach to the treatment of obesity. Behav Res Ther 2001; 39: 499–511.
Cooper Z, Fairburn CG, Hawker DM . Cognitive-Behavioral Treatment of Obesity: A Clinician's Guide. Guilford Press: New York, 2003.
Dalle Grave R, Calugi S, Molinari E, Petroni ML, Bondi M, Compare A et al. Weight loss expectations in obese patients and treatment attrition: an observational multicenter study. Obes Res 2005; 13: 1961–1969.
Jeffery RW, Wing RR, Mayer RR . Are smaller weight losses or more achievable weight loss goals better in the long term for obese patients? J Consult Clin Psychol 1998; 66: 641–645.
Ames GE, Perri MG, Fox LD, Fallon EA, De Braganza N, Murawski ME et al. Changing weight-loss expectations: a randomized pilot study. Eat Behav 2005; 6: 259–269.
Finch EA, Linde JA, Jeffery RW, Rothman AJ, King CM, Levy RL . The effects of outcome expectations and satisfaction on weight loss. Health Psychol 2005; 24: 608–616.
Foster GD, Phelan S, Wadden TA, Gill D, Ermold J, Didie E . Promoting more modest weight losses: a pilot study. Obes Res 2004; 12: 1271–1277.
Wadden TA, Berkowitz RI, Womble LG, Sarwer DB, Phelan S, Cato RK et al. Randomized trial of lifestyle modification and pharmacotherapy for obesity. N Engl J Med 2005; 353: 2111–2120.
Brownell KD . The LEARN Program for Weight Control 7th edn American Health Publishing: Dallas, 1998.
Brownell KD, Rodin J . The Weight Maintenance Survival Guide. Brownell & Hager: Dallas, 1990.
Brownell KD, Wadden TA . The LEARN Program for Weight Control: Special Medication Edition. American Health Publishing: Dallas, 1999.
Beck AT, Steer RA, Brown BK . Beck Depression Inventory Manual, 2nd edn Psychological Corporation: San Antonio, 1996.
James WPT, Astrup A, Finer N, Hilsted J, Kopelman P, Rossner S et al. Effect of sibutramine on weight maintenance after weight loss: a randomised trial. Lancet 2000; 356: 2119–2125.
Wadden TA, Butryn ML . Behavioral treatment of obesity. Endocrinol Metab Clin North Am 2003; 32: 981–1003.
Celio AA, Zambinski MF, Wilfley DE . African American body images. In: Cash TF, Pruzinski T (eds.) Body Image: A Handbook of Theory, Research, and Clinical Practice. Guilford Press: New York, 2002. pp 234–242.
National Institutes of Health/National Heart Lung and Blood Institute. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: the evidence report. Obes Res 1998; 6: 51S–210S.
Wadden TA, Brownell KD, Foster GD . Obesity: responding to the global epidemic. J Consult Clin Psychol 2002; 70: 510–525.
This study was supported in part by the following grants from the National Institutes of Health: K23-DK070777 to Dr Fabricatore; K24-DK065018 and R01-DK56124 to Dr Wadden and K23-DK60023 to Dr Sarwer. We thank Jennifer L Krasucki, Christopher I Wilson and Daniéle M Bourget for assistance in the preparation of this manuscript.
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Fabricatore, A., Wadden, T., Womble, L. et al. The role of patients' expectations and goals in the behavioral and pharmacological treatment of obesity. Int J Obes 31, 1739–1745 (2007). https://doi.org/10.1038/sj.ijo.0803649
- weight loss
- weight regain
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