INTRODUCTION — Behavior modification is an essential component of a weight loss strategy, whether used alone or in combination with pharmacotherapy or bariatric surgery [1,2]. Diet change alone can produce a weight loss of 5 to 10 percent below baseline weight, with comprehensive lifestyle modifications (combination of diet change, exercise, and behavioral interventions) resulting in even greater weight loss [3,4]. The use of behavioral strategies to treat obesity in adults is reviewed here. Other therapies for obesity, including drug therapy, specific diets, exercise, and bariatric surgery, are reviewed separately. Issues of obesity in children, adolescents, and pregnant women are also reviewed separately.
●(See "Obesity in adults: Overview of management".)
●(See "Obesity in adults: Role of physical activity and exercise".)
●(See "Obesity in adults: Dietary therapy".)
●(See "Obesity in adults: Drug therapy".)
●(See "Bariatric surgery for management of obesity: Indications and preoperative preparation".)
●(See "Definition, epidemiology, and etiology of obesity in children and adolescents".)
●(See "Obesity in pregnancy: Complications and maternal management".)
IMPORTANCE OF BEHAVIORAL THERAPY — More than two-thirds of adults in the United States are either trying to lose weight or maintain their weight at any given time. However, only 20 percent are both eating fewer calories and exercising on a regular basis. Thus, all clinicians can play an important role in educating people regarding the optimal strategies for losing weight and/or maintaining lost weight. Behavioral-based treatment programs improve weight loss results and are associated with improvements in obesity-associated morbidity [4]. The US Preventive Services Task Force (USPSTF) recommends that all adults with a body mass index (BMI) ≥30 be offered intensive, multicomponent, behavioral interventions to achieve and maintain weight loss [5]. (See 'Efficacy' below and "Obesity in adults: Overview of management", section on 'Goals of treatment'.)
Patients who report receiving weight loss advice from a health care provider more frequently report behavior change attempts (77 versus 33 percent) [6] and weight loss [7]. Clinicians, including nurse practitioners, nurse specialists, and physician assistants, can be reimbursed for providing intensive behavioral therapy for patients with obesity in the primary care setting [8]. Alternately, patients can be referred to Registered Dietitian Nutritionists (RDs or RDNs), who are the clinical experts in providing comprehensive medical nutrition therapy for obesity treatment [9]. In the United States, insurance coverage for nutritionist evaluation varies, with some insurers only covering such care for patients with diabetes.
WHAT IS BEHAVIORAL THERAPY? — Behavior modification or behavior therapy is considered to be an essential component of managing the patient with overweight or obesity. The goals are to help patients make long-term changes in their eating behavior by:
●Modifying and monitoring their food intake
●Modifying their physical activity
●Controlling cues and stimuli in the environment that trigger eating and overeating
A principal determinant of weight loss appears to be the degree of adherence to the chosen program [10]. Thus, patient preference is an important consideration when recommending any behavioral weight loss program (see 'Choice of intervention' below). The concepts described are included in most behavioral therapy programs conducted by trained providers, such as registered dietitian nutritionists (RDs or RDNs) and psychologists, as well as many self-help groups.
The assumption underlying behavioral therapy is that improving health behaviors, primarily those related to eating and activity, reduces the risk of chronic disease and provides health benefits; these benefits are often conferred via weight loss [8].
Behavioral treatment for the patient who has overweight or obesity seeks to:
●Alter the environment
●Alter environmental reinforcement contingencies
●Shape eating behavior and physical activity
●Provide health benefits by reducing the risk for developing diseases associated with obesity [11]
It is important to recognize that behavior change is complex and often challenging, especially given the availability and appeal of highly caloric foods and sedentary behaviors in modern society [12,13]. Important, too, are the contributions of the social determinants of health; food access and insecurity are linked to obesity, as are other stressors related to poverty and racism [14].
Elements of behavior change — Comprehensive lifestyle interventions usually provide a structured behavioral program that includes a number of components [15-17]. These can be broadly categorized as nutrition education and self-regulation.
Nutrition education focuses on providing motivation (why to) and facilitation (how to) towards a specific behavioral goal (eg, drinking water instead of sugary beverages) and often also encompasses physical activity behaviors in addition to nutrition behaviors. Motivating factors include social support, understanding the benefits of behavior change and risks of not changing behavior, and self-efficacy. Facilitating factors include knowledge and skills [18].
Self-regulation includes a set of supportive behaviors that have been demonstrated to improve initiation and maintenance of a behavior change goal, such as:
●Goal setting
●Self-monitoring (keeping food diaries and activity records)
●Controlling or modifying the stimuli that activate eating
●Eating style (slowing down the eating process)
●Behavioral contracting and reinforcement
●Meal planning
●Cognitive restructuring
●Problem solving
These same elements of behavior change are recommended to maintain weight loss, especially physical activity and periodic weight monitoring.
Furthermore, it is important to consider the influence on energy balance related behaviors proposed in the socioecological model: internal, social, community, and policy [9].
Setting weight loss goals — Changes in eating behavior require time and commitment, and it is important for the patient and health care provider to set weight loss goals, such as 0.5 to 1 kg/week, or 5 to 10 percent of baseline weight within six months [19]. To achieve this goal, patients are encouraged to reduce energy intake by 500 kcal/day, which can be done with diet instruction, provision of food, or the use of portion-controlled foods. Evidence from the Look AHEAD (Action for Health in Diabetes) trial shows that individuals with larger month-to-month weight losses and more sustained weight loss during the first year had better maintenance of weight loss over four years, independent of characteristics traditionally linked to weight loss success [20,21]. (See "Obesity in adults: Dietary therapy", section on 'Goals of weight loss'.)
Setting behavioral goals — It is likewise important to set behavioral goals. These goals are Specific, Measurable, Achievable, Reasonable, and Time-bound (SMART), and should be within a patient’s control. Some examples include: make half of your plate fruits and vegetables, and eat fast food less than once a week [18].
Self-monitoring — Self-monitoring, often involving the use of food diaries, activity records, and self-weighing, is one of the elements of a successful behavioral weight loss program [22-27]. No single strategy for self-monitoring (eg, activity trackers) has been shown superior to the others, but the overarching concept of self-monitoring is critical. Patients should be encouraged to record everything they eat, the calories in the food, and the situation in which they are eating.
The National Weight Control registry, a study of 4000 individuals who had lost at least 30 lbs (13.6 kg) and kept it off for at least one year, reports that self-monitoring is one of the most frequently used techniques among patients who successfully lose weight and maintain the weight loss [24]. In a systematic review of 22 studies evaluating the relationship between self-monitoring and weight loss, there was a consistent association between self-monitoring (of weight, diet, and exercise) and successful weight loss [25]. A variety of methods were used to perform self-monitoring, including paper diaries, internet applications, smartphone applications, and digital scales for recording weight.
Stimulus control — Stimulus control is another element in a behavioral program [15]. It focuses on gaining control over the environmental factors that trigger eating and eliminating or modifying the environmental factors that facilitate overeating. Since food is a key issue in weight gain, participants are taught to buy more fresh fruits and vegetables, to prepare easy-to-eat lower calorie foods, and to place them prominently in the refrigerator or on the counter.
Stimulus control also includes making the act of eating a focus of its own. Thus, turning off the television set and putting down reading materials may allow the individual to concentrate on eating. Stimulus control in children who substituted active behaviors for sedentary behaviors was associated with a significantly smaller rise in age and gender-adjusted body mass index (BMI) scores at 6 and 12 months [28].
Eating style — Slowing down the eating process may give time for "physiologic" signals for fullness to come into play. “Mindful eating” includes concentrating on the tastes and textures of food and savoring what is being eaten by chewing more slowly; this technique can slow down eating. Other techniques might involve leaving the table briefly during a meal and drinking water between bites or just prior to the meal [29].
Regular weighing — Regular self-weighing as a strategy for self-monitoring has been recommended in some studies [30,31]. There were concerns that regular weighing might lead to anxiety and weight regain, but this was not observed in a systematic literature review of 17 studies [32].
Behavioral contracting and reinforcement — Reinforcing successful outcomes by providing rewards for weight loss may be beneficial [33,34]. As an example, in a 24-week trial, 105 employees (BMI 30 to 40 kg/m2) were randomly assigned to a financial incentive reward group (either as individuals or as members of a five-member group) or to a control group with monthly weigh-ins [34]. The financial reward was distributed at the end of each month to individuals who met a prescribed weight loss target. The group-incentive participants shared the reward (which was five times the individual reward) evenly but only among those who met the target weight loss goal. The five members of the group were unknown to each other. The group-incentive participants lost significantly more weight than individual-incentive and control groups (4.8, 1.7, and 0.5 kg, respectively) and also received larger payouts than individual-incentive participants (USD $514 versus $128 over five months). The opportunity to earn a larger reward, by acquiring the incentive that other group members forfeited by not meeting the monthly goal, may have been a motivating factor for group-incentive participants. This suggests that variable incentives within a group may be better than specified individual ones.
In contrast with financial incentives, social contingency, ie, having access to the group only if the participant met specific weight loss goals, did not improve weight loss [35].
Portion control and meal planning — Portion control and meal planning are also helpful behavioral strategies. Providing a defined meal structure results in greater weight loss than the absence of such a structure [24]. Use of portion-controlled plates [36] or meal replacements are examples of such strategies.
Use of meal replacements enhanced weight loss, albeit modestly, in the Look AHEAD trial over the first four years. However, their use diminished over the next eight years in the trial, as did their relationship to successful weight loss [37].
In addition, patients experiencing food insecurity should be referred to nutrition assistance programs, such as Supplemental Nutrition Assistance Program (SNAP) and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). SNAP participation is associated with less obesity and healthier diet [38].
Increasing physical activity — Increasing physical activity is another part of a successful behavioral program [19]. Along with self-monitoring, increasing physical activity was a key element in success for members of the National Weight Control Registry, a group of more than 4000 individuals who had lost at least 13.6 kg (30 lbs) and kept it off for at least one year [24]. These individuals had lost an average of 33 kg and maintained it for an average of 5.7 years. Women in the Registry reported expending 2545 kcal/week in exercise and men 3293 kcal/week in exercise. This would be equivalent to approximately one hour/day of moderate-intensity activity, such as brisk walking [24]. In addition, the amount of weight lost in the Look AHEAD trial over eight years was related to the amount of physical activity [37].
However, the characteristics of behavioral programs that best predict weight loss are still unclear. In a meta-analysis of 37 randomized trials of multicomponent behavioral weight management programs, calorie counting, contact with a dietitian, and use of certain behavior change techniques were associated with greater weight loss than supervised physical activity sessions [16]. The role of exercise in obesity is reviewed in detail separately. (See "Obesity in adults: Role of physical activity and exercise".)
Social support — Enhancing social support may also be a means for improving long-term weight loss [39]. Inclusion of family members or spouses is one way to accomplish this [40]. There are both short- and long-term benefits to programs that include strong family support. In a meta-analysis of four 12-month behavioral programs that included family members, mean weight loss in the family-based intervention was approximately 3 kg more than in the control behavioral programs [41].
Social support can also work to the advantage of the family member not participating in the trial. In the Look AHEAD trial, which is a randomized trial of intensive lifestyle modification in patients with type 2 diabetes, the spouses of those in the intervention group lost 2.2 to 4.4 kg, whereas spouses of those in the control group gained up to 3.3 kg in body weight [42]. The Look AHEAD trial is reviewed separately. (See "Initial management of hyperglycemia in adults with type 2 diabetes mellitus", section on 'Intensive lifestyle modification'.)
Other tools — Although there is no high-quality evidence to demonstrate the efficacy of these techniques, a number of additional behavioral tools may help with weight loss:
●Cognitive restructuring – Adopting positive rather than negative self-talk (for example, if one eats a piece of cake, choosing to exercise rather than blaming oneself)
●Problem-solving – Developing strategies to manage food intake in difficult situations such as restaurants and parties
●Assertiveness training – Learning to say "no"
●Stress reduction – Identifying and reducing stressors that are triggers for eating
Efficacy
Behavioral-based programs — Behavioral-based treatment programs improve weight loss results [1,3,37,43,44]. Multicomponent interventions that include dietary modification, exercise, pharmacotherapy, and counseling on behavioral strategies are more effective than interventions that focus on a single component.
A meta-analysis of 122 randomized controlled trials and two observational studies compared an intensive, multicomponent behavior-based weight loss intervention with a comparison group receiving the usual care [4]. At 12 to 18 months, patients receiving multicomponent behavior-based interventions were more likely to achieve a 5 percent or greater weight loss (risk ratio [RR] 1.94, 95% CI 1.70-2.22). Among those patients with prediabetes, the intervention reduced the risk of developing diabetes (RR 0.67, 95% CI 0.51-0.89).
Another systematic review found interventions that combined dietary therapy (reduced energy intake), increased physical activity, and counseling on behavioral strategies to be more successful in reducing weight than interventions without all three components [3].
Multicomponent behavior-based weight loss interventions may also produce sustained weight loss. As an example, in the Look AHEAD trial, which compared an intensive lifestyle intervention with a diabetes support and education control group, weight loss was greater with the intervention group at one year (8.6 versus 0.7 percent of body weight) and four years (6.2 versus 0.9 percent) [45]. At eight years, over half of the intervention group maintained a weight loss of >5 percent of their baseline weight (50 versus 36 percent) [37]. (See "Obesity in adults: Overview of management", section on 'Importance of weight loss'.)
Similar behavioral models for weight loss have been applied in "real-world" settings. The Centers for Disease Control and Prevention (CDC)-sponsored National Diabetes Prevention Program (NDPP) has adopted behavioral therapy approaches from clinical trials (Diabetes Prevention Program [DPP] and Look AHEAD) to primary care practices and YMCA programs with demonstrated success [46-50].
Further, an intensive lifestyle intervention program delivered through a primary care setting to adults in a low-income population has also been shown to be effective [51].
Self-help or commercial weight loss programs — Self-help or commercial weight loss programs incorporate varying degrees of behavioral modification strategies. They can be expensive and employ very low-calorie diets, and only some have been evaluated in controlled clinical trials [52-55]. Since the commercial programs do not carry any higher risk than other dietary programs, the patient and health care provider can select among programs, with the recommendation that programs with clinically demonstrated efficacy be the first choice (eg, Weight Watchers, Jenny Craig). Because adherence to weight loss programs is important for long-term success, patient preference is another important consideration when recommending any weight loss program. Additional detail about dietary therapy is reviewed separately. (See "Obesity in adults: Dietary therapy".)
A 2015 systematic review of the major available programs in the United States (Weight Watchers [eight trials], Jenny Craig [three trials], Nutrisystem [three trials], Health Management Resources [HMR; four trials], Medifast [one trial], Optifast [four trials], Atkins [eight trials], The Biggest Loser Club [one trial], eDiets [one trial], Lose It! [one trial], and SlimFast [eight trials]) reported outcomes based upon a variety of measures, including lead market share, duration of intervention, and total calories [56]. The three largest commercial programs were Weight Watchers, Jenny Craig, and Nutrisystem.
Compared with a control/education group (no intervention, printed materials, health education, or limited sessions with a clinician) or behavioral counseling, participants in the following programs achieved significantly greater weight loss at 12 months:
●Weight Watchers participants achieved 2.6 percent greater weight loss
●Jenny Craig participants achieved 4.9 percent greater weight loss
In addition, participants who followed an Atkins diet achieved 0.1 to 2.9 percent greater weight loss than controls at 12 months [10]. Some very low-calorie meal replacement programs (HMR, Medifast, and Optifast) result in short-term weight loss outcomes superior to those of control/education and behavioral counseling, but whether these results can be sustained in the long term is unclear (see 'Maintenance of weight loss' below). Additional details about dietary therapy are reviewed separately. (See "Obesity in adults: Dietary therapy".)
Technology-based programs — Technology-based programs for weight management have become widely available, including digital programs and applications ("apps") for use on the internet, including those designed for use with mobile and "smart" devices. Such programs are particularly appealing due to ease of use and convenience. Use of such digital technology has been demonstrated to improve adherence with self-monitoring and is associated with weight loss [57].
●Internet-based weight loss programs – Internet-based weight loss programs are widely available, including self-help and commercial weight loss programs that historically used only in-person group meetings [58-66]. Available data suggest that programs with a behavior modification component are more effective than those without.
•Important elements include guidance and feedback from a trained interventionist and high-intensity treatment that lasts six months with at least 14 sessions. This approach is based on the face-to-face experience in studies where success is proportional to the frequency of interactions. In one report, patients who received 20 calls over six months lost an average of 4.9 kg compared with 3.2 and 2.3 kg, respectively, for those receiving either 10 or no calls [67]. Telephone-based counseling may also be effective for maintaining weight loss [68].
•A low-intensity, weekly email intervention is more effective if weekly lifestyle modification counseling is added [69]. Individual support from an interventionist/coach is particularly effective.
●Mobile apps – Mobile apps are popular, although there is a wide range of quality and efficacy in available apps.
In several systematic reviews and meta-analyses, the use of mobile apps had beneficial effects on nutrition behaviors and weight loss [70-75]. As examples:
•In a meta-analysis of 41 studies (including 27 randomized controlled trials) and over 6000 participants, the use of mobile apps changed dietary behavior, including reduced caloric intake and increased fruit and vegetable consumption [70]. Of the 29 trials that recorded weight, use of a mobile app was associated with a modest weight loss (-2.7 kg, 95% CI 0.64 to -9.65 kg). The addition of other intervention components was not associated with an increase in efficacy.
•In a meta-analysis including 14 randomized controlled trials and over 2000 patients with type 2 diabetes mellitus, the use of mobile apps resulted in weight loss and reduced waist circumference (-0.84 kg, 95% CI -1.51 to -0.17 kg and -1.35 cm, 95% CI -2.16 to -0.55 cm, respectively), although there was no change in BMI [71]. Weight loss was greater in patients with obesity and when mobile apps were combined with other interventions.
Effective apps include active features, such as [76]:
•Bi-directional (interactive) features, with personal messages
•Personalized goal-setting and self-monitoring
However, app-based self-monitoring can also be time-consuming and frustrating for some users [77].
While commercially available apps are likely to be encountered in the clinical setting and may be recommended by providers or independently adopted by patients, it is important to recognize that there is extreme variability in their scientific accuracy, use of evidence-based behavior change techniques, and ease of use. Many commercially available apps are of suboptimal quality and lack evidence of efficacy. Furthermore, they are not subject to regulatory oversight, potentially to users’ detriment [78,79].
A small number of commercially developed apps have been evaluated in the research literature, typically by the commercial developer along with academic collaborators. For example, in observational studies, the use of the Noom app is associated with weight loss; greater weight loss was seen in older compared with younger adults, and a higher level of engagement was associated with greater weight loss [80-82].
OUR APPROACH — We suggest that patients choose the behavioral program that best fits their needs, as long as it includes the essential elements outlined above. (See 'Elements of behavior change' above.)
There are a number of behavioral approaches that can achieve weight loss goals, including face-to-face (individual or group), internet-based, and mobile applications. While some patients might prefer individual therapy, such therapy may be cost prohibitive. The group setting may be more cost effective, and there is insufficient evidence to conclude that one is superior to the other [19,83,84]. All interventions use similar behavioral strategies, which are outlined above. (See 'Elements of behavior change' above.)
Interventions can be delivered in a variety of different settings, including health care offices, gyms/ health clubs, and commercial weight loss centers. (See "Obesity in adults: Role of physical activity and exercise", section on 'No increased weight loss with use of "activity trackers"'.)
Choice of intervention — For people with overweight or obesity who are attempting to lose weight, we suggest weight loss programs that include behavior modification. There are several features that may improve the likelihood of success:
●Patient preference is an essential consideration when recommending any behavioral weight loss program; the degree of adherence to the program is an important predictor of weight loss.
●Combining behavioral therapy with other methods can enhance the magnitude and duration of weight loss. For example, behavioral therapy (that includes the elements described above), combined with dietary therapy (reduced energy intake) and increased physical activity, is more successful in reducing weight than interventions without all three components. (See 'Elements of behavior change' above and 'Efficacy' above.)
●A high-intensity program (at least 12 sessions over six months) with frequent reinforcement is more likely to be successful than a shorter program [85]. In addition, programs of greater length are more effective than those of shorter length [19]. In the 1970s, behavioral weight loss programs typically lasted eight weeks with an average weight loss of 3.8 kg, but by the 1990s, as treatment duration lengthened, typical weight loss was 8.5 kg after 21 weeks of treatment [86]. (See 'Behavioral-based programs' above.)
●Regular patient education on healthy diet choices, physical activity, weight loss goals, and barriers to weight loss, as well as regular weight checks and peer support, help facilitate weight loss. (See 'Behavioral-based programs' above.)
●Mobile app-based self-monitoring interventions may be effective in supporting weight loss, either alone or in tandem with other interventions.
Maintenance of weight loss — For patients who have obesity or overweight and who have lost weight, we suggest the continuation of behavior modification strategies that target diet and physical activity to minimize subsequent weight gain [26,63,66,87,88].
Weight regain is a common phenomenon and is likely related to metabolic adaptation processes that decrease energy expenditure in response to weight loss [89]. High levels of physical activity have been demonstrated to be protective against weight regain [90]. The role of exercise in the maintenance of weight loss is reviewed elsewhere. (See "Obesity in adults: Role of physical activity and exercise", section on 'Exercise importance in maintenance of weight loss'.)
In a meta-analysis of 45 trials including over 7700 individuals who initially had lost ≥5 percent of body weight, subsequent behavioral interventions showed a small but significant benefit compared with controls (mean difference in weight regain -1.56 kg) [91]. Some [26,87], but not all [63], trials suggest that individuals receiving face-to face interventions may initially regain less weight than those receiving internet-based interventions, but both groups eventually regain similar amounts of weight [87]. However, in a subsequent weight-loss maintenance trial not included in this meta-analysis, those participating in electronic health record (EHR) tracking and receiving internet-based coaching through their EHR patient portal regained less weight over two years than those participating in EHR health tracking alone (2.07 versus 4.93 kg) [92].
Follow-up phone calls providing maintenance training and support may also help prevent weight regain. In a randomized trial comparing a phone-based weight loss maintenance program (relapse prevention techniques, self-monitoring, and social support) with usual care (no contact except for weight measurements) including 222 middle-aged men who had lost ≥4 kg during the previous 16 weeks, mean weight regain over the subsequent year was lower in the intervention compared with the control group (0.75 versus 2.4 kg, respectively) [93].
Although many individuals succeed in losing weight with diet and/or behavioral therapy, most patients subsequently regain most of the lost weight. These up-and-down periods, sometimes referred to as "weight cycles," enhanced the risk of developing diabetes in the Diabetes Prevention Program (DPP) [94].
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Obesity in adults".)
SUMMARY AND RECOMMENDATIONS
●Behavioral-based treatment programs improve weight loss results and are associated with improvements in obesity-associated morbidity. The US Preventive Services Task Force (USPSTF) recommends that all adults with a body mass index (BMI) ≥30 be offered intensive, multicomponent, behavioral interventions to achieve and maintain weight loss. (See 'Importance of behavioral therapy' above.)
●Behavior modification or behavior therapy is considered to be an essential component of managing the patient with overweight or obesity. The goals are to help patients make long-term changes in their eating behavior by:
•Modifying and monitoring their food intake
•Modifying their physical activity
•Controlling cues and stimuli in the environment that trigger eating and overeating
A principal determinant of weight loss appears to be the degree of adherence to the chosen program. In addition, physical activity and self-monitoring are particularly important components for success. (See 'What is behavioral therapy?' above.)
●For patients who are overweight or obese and who are attempting to lose weight, we suggest weight loss programs that include behavior modification strategies (Grade 2B). A high-intensity program (at least 12 sessions over six months) with frequent reinforcement is preferred. (See 'Our approach' above.)
●A principal determinant of weight loss appears to be the degree of adherence to the program. Thus, patient preference is an essential consideration when recommending any behavioral weight loss program. Some may prefer the convenience and possible lower cost of internet programs or mobile apps, while others may prefer the support provided by individual or group sessions. (See 'Our approach' above.)
●For patients who are overweight or obese and who have lost weight, we suggest that behavior modification strategies that target diet and physical activity be continued to minimize subsequent weight gain (Grade 2B). (See 'Maintenance of weight loss' above.)
ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges George Bray, MD, who contributed to an earlier version of this topic review.
