Position ada weight manegement


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Position ada weight manegement

  1. 1. from the association Position of the American Dietetic Association: Weight Management This paper endorsed by the American College of Sports MedicineABSTRACT This Position of the American Dietetic Association (ADA) uses ADA’sIt is the position of the American Evidence Analysis Process and information from ADA’s Evidence AnalysisDietetic Association that successful Library. The use of an evidence-based approach provides important addedweight management to improve benefits to earlier review methods. The major advantage of the approach isoverall health for adults requires a the more rigorous standardization of review criteria, which minimizes thelifelong commitment to healthful likelihood of reviewer bias and increases the ease with which disparatelifestyle behaviors emphasizing sus- articles may be compared. For a detailed description of the methods used intainable and enjoyable eating prac- the evidence analysis process, access the ADA’s Evidence Analysis Processtices and daily physical activity. at http://adaeal.com/eaprocess/.Given the increasing incidence of Conclusion statements are assigned a grade by an expert work groupoverweight and obesity along with the based on the systematic analysis and evaluation of the supporting researchescalating health care costs associ- evidence. Grade I Good; Grade II Fair; Grade III Limited; Gradeated with weight-related illnesses, IV Expert Opinion Only; and Grade V Grade is Not Assignable (becausehealth care providers must discover there is no evidence to support or refute the conclusion).how to effectively treat this complex Recommendations are also assigned a rating by an expert work groupcondition. Food and nutrition profes- based on the grade of the supporting evidence and the balance of benefit vssionals should stay current and harm. Recommendation ratings are Strong, Fair, Weak, Consensus, orskilled in weight management to as- Insufficient Evidence. Recommendations can be worded as conditional orsist clients in preventing weight gain, imperative statements. Conditional statements clearly define a specific sit-optimizing individual weight loss in- uation and most often are stated as an “if, then” statement, whereasterventions, and achieving long-term imperative statements are broadly applicable to the target populationweight loss maintenance. Using the without restraints on their pertinence. Evidence-based information forAmerican Dietetic Association’s Evi- this and other topics can be found at www.adaevidencelibrary.com anddence Analysis Process and Evidence subscriptions for nonmembers are purchasable at www.adaevidencelibrary.Analysis Library, this position paper com/store.cfm.presents the current data and recom-mendations for weight management.The evidence supporting the value of ment to healthful lifestyle behaviors em- signed to primarily protect againstportion control, eating frequency, phasizing sustainable and enjoyable starvation (4). Despite the volume ofmeal replacements, and very-low-en- eating practices and daily physical ac- research, there have been only a lim-ergy diets are discussed as well as tivity. ited number of obesity cases identi-physical activity, behavior therapy, fied as being directly caused by a sin- Opharmacotherapy, and surgery. Pub- besity is a condition character- gle gene mutation (5).lic policy changes to create environ- ized by excess accumulation of On a population level, changes inments that can assist all populations adipose tissue (ie, fat stores). obesity prevalence can also be viewedto achieve and sustain healthful life- Fat stores can only be changed by a as an aberration of energy balancestyle behaviors are also reviewed. whole body energy imbalance brought but on a larger scale. Agricultural ad-J Am Diet Assoc. 2009;109:330-346. on by a change in energy intake, en- ergy output, efficiency of energy use, vances, changes in economy and tech- or a combination of any of these com- nology (6), as well as societal changesPOSITION STATEMENT ponents (1). The underlying genetic influencing expectations and valueIt is the position of the American Die- and physiologic mechanisms govern- systems (7), have lead to a worldtetic Association that successful weight ing these three energy-balance com- where the energy of the food supplymanagement to improve overall health ponents have been intensely studied most frequently exceeds that of thefor adults requires a lifelong commit- (although still far from being com- opportunities for energy expenditure pletely understood) (2,3). This re- through physical activity. The com- search has greatly expanded since the plexity of the causal factors at the 0002-8223/09/10902-0016$36.00/0 discovery of leptin in the early 1990s individual level combined with the doi: 10.1016/j.jada.2008.11.041 and has revealed a physiology de- complexity of causal factors affecting330 Journal of the AMERICAN DIETETIC ASSOCIATION © 2009 by the American Dietetic Association
  2. 2. the environment within which indi- mal BMI range. In addition, it is im- into their patients’ individualized careviduals live leads to a high prevalence portant to set realistic expectations plans.of a condition that is often described about the time required to make aas chronic and refractory with a high sustainable behavior change.recidivism rate for its treatment (8). Goals of weight management inter- ASSESSMENT OF OBESITY Given the biological tendency to ventions may include: Assessment, the first step of the Nu-protect against starvation and the so- trition Care Process (13,14), involvescietal tendency to protect against un- ● prevention of weight gain or stop- gathering the necessary informationderconsumption and volitional physi- ping weight gain in an individual to formulate a diagnosis and developcal activity, there are clear pathways who has been seeing a steady in- a care plan. Baseline weight andfor action. First, the one in three crease in his or her weight; health indexes should guide weightadults (9) who can currently maintain ● varying degrees of improvements in management goals and are necessarya healthful body mass index (BMI) physical and emotional health; to document outcomes. Clinically use-are not likely to continue to be able to ● small maintainable weight losses ful measures of body weight statusdo so if no action is taken. Curbing or more extensive weight losses are noninvasive, easy to use, inexpen-the weight gain trajectory at both the achieved through modified eating sive, reliable, capable of reflectingindividual and population levels is vi- and exercise behaviors; and short- and long-term changes in bodytally important. Next, it is crucial ● improvements in eating, exercise, fat, and must be correlated to healththat we find ways to optimize individ- and other behaviors. risk.ualized treatments appropriately. Fi- The standard measurement fornally, with the most rapidly growing Health can be improved with rela- weight status is BMI, calculated aspopulation category being those who tively minor weight losses. A weight kg/m2. Overweight is defined as aare severely obese (10), it is necessary loss of 10% may ameliorate health BMI of 25 to 29, whereas higherto understand and effectively treat risks associated with excessive body BMI values reflect more excessivethat portion of the population whose weight (12). Health care providers amounts of body fat (12). There arehealth is most greatly compromised must help patients to accept a mod- differences even in the community ofby this condition. est, sustainable weight change that experts as to the BMI at which an The purpose of this position paper can be realistically achieved. Appear- individual is at greater health risk.is to outline the evidence supporting ance, in many patients, will be an im- Some advocate weight loss by individ-The American Dietetic Association’s portant motivator; however, it is crit- uals with a BMI of 25 to 29 but debate(ADA’s) adult weight management ical that health care providers continues on how much weight reduc-position statement. Since 2000, ADA emphasize the goal of achieving a tion should be recommended (15). Thehas used an evidence-based approach more healthful weight and lifestyle National Heart, Lung, and Blood In-for the development of clinical prac- while de-emphasizing cosmetic goals. stitute (NHLBI) guidelines (16) rec-tice guidelines for nutrition care. The ommend intervention for overweightevidence analysis work for the adult individuals who have two or moreweight management guidelines form risk factors associated with theirthe basis of the information provided weight status. The Dietary Guidelinesin this position paper (11). The recom- The goals of weight for Americans 2005 (17) recommendmendation statement from the adult management go well individuals work toward weight re-weight management guidelines is in- duction if they are even mildly over-cluded in this position paper in all beyond numbers on a weight.sections where there is a correspond- scale, whether or not Multiple sources of information areing major recommendation from the available, but for most evaluations aguidelines. A brief description of the weight change is one patient-centered interview with sup-evidence analysis process, an expla- of the management porting records from primary carenation of the conclusion statement providers and/or referring physiciansgrading, and the recommendation objectives. remain the most important. A physi-rating scales is provided in the Side- cian’s evaluation of weight status, in-bar. ADA’s Nutrition Care Process in- cluding height, weight, and waist cir- cludes nutrition assessment, nutri- cumference, provides the information tion diagnosis, nutrition intervention, indicating that a referral to a regis-GOALS OF WEIGHT MANAGEMENT and nutrition monitoring and evalua- tered dietitian (RD) is appropriate. AThe goals of weight management go tion. It is essential to include each of medical examination should rule outwell beyond numbers on a scale, these steps into weight management physiologic causes of increased bodywhether or not weight change is one care plans. ADA’s Evidence Analysis weight and assess health risks and/orof the management objectives. The Library (EAL) contains evidence- the presence of weight-related co-development of healthful lifestyles based adult weight management morbidities. Cardiorespiratory fit-with behavior modification is impor- guidelines, including the recommenda- ness and screening for musculoskele-tant for overall fitness and health. Re- tions upon which this position paper is tal problems may need to be reviewedalistic expectations should be defined based (11). Food and nutrition profes- before making physical activity rec-during an intake interview in terms sionals should incorporate these funda- ommendations or referring on to anof a more healthful weight vs the nor- mental concepts for managing obesity exercise professional. In addition to a February 2009 ● Journal of the AMERICAN DIETETIC ASSOCIATION 331
  3. 3. medical assessment, a psychologicalevaluation may be indicated. Screen- A. Anthropometricsing for barriers to successful weight ● Heightloss such as depression, post-trau- ● Weightmatic stress disorder, anxiety, bipolar ● Body mass indexdisorder, addictions, binge eating dis- ● Waist circumferenceorder, and bulimia is necessary. Stud- B. Medicalies have shown a high frequency of ● Identify potential causes: endocrine, neurological; medications; genetics (age of onset,these disorders in those with exces- family history).sive weight problems (18-20). Appro- ● Identify obesity-associated disorders (current complications and risk of futurepriate treatment should be imple- complications): metabolic, anatomic, degenerative, and/or neoplastic complications.mented before beginning a nutritional ● Evaluate obesity severity and extent of physical disability.intervention. C. Psychological With this information from the ● Identify psychological etiology: psychotropic medications, depression, post-traumatichealth care team, an RD can effec- stress disorder, addictive behavior.tively begin evaluation. ● Eating disorders: binge eating, bulimia. EAL Recommendation “BMI and ● Assess risk for potential barriers to treatments: psychiatric history—suicidal ideation,waist circumference should be used to untreated psychological disorders.classify overweight and obesity, esti- D. Nutritional ● Weight history: age of onset, highest/lowest adult weights, patterns of weight gain andmate risk for disease, and to identify loss, environmental triggers to weight gain, triggers to excessive or disordered eating.treatment options. BMI and waist cir- ● Dieting history: number and types of diets, weight loss medications, complementary andcumference are highly correlated to alternative approaches for weight loss, success of previous weight loss efforts.obesity or fat mass and risk of other ● Current eating patterns: meal patterns (skipped meals, largest meal, snacks/grazing),diseases” (Rating: Fair, Impera- 24-hour recall/food frequency.tive) (11). Data is accumulating re- ● Nutritional intake: nutrient density, nutrition supplements, vitamin/mineral supplements.garding differences in aboriginal and ● Environmental factors: meals eaten away from home, fast-food meals, restaurant meals,Asian racial groups that may indicate ethnic foods, lifestyle factors (eg, time and/or financial constraints).a downward shift of BMI to define a ● Exercise history: activities of daily living, current structured exercise, past exercise,healthful weight is indicated (21-23). barriers to exercise. Functional and behavioral issues ● Readiness to change: reasons to lose weight at this time, weight loss goals, readiness for(eg, social and cognitive function, psy- making changes, current life stressors, support systems.chological and emotional factors, andquality-of-life measures) are impor- Figure. Factors to assess during weight management intake interviews.tant to address to optimize a weightmanagement intervention. Factorsrelated to food access, food selection, part of an assessment. However, met- height in centimeters)–(5 age infunctional capacity for food prepara- abolic carts are rarely available in years) 5.tion, and other physical activity are clinical practice and another sched- Woman: Basal Metabolic Rate (BMR)significant for treatment planning. uled visit may be required to provide (10 weight in kilograms) (6.25 During an intake interview it is im- standard conditions for cart measure- height in centimeters)–(5 age inportant to observe nonverbal and ver- ment. There is controversy regarding years)–161.bal cues. These cues can guide and the applicability of predictive equa-prompt the interviewing process and tions of resting energy expendi- Determining when a problem re-help determine what information ture; however, such information can quires consultation with or referral toshould be prioritized and evaluated make a valuable contribution to goal another provider may be appropriate.further. In many dietetic referrals setting and intervention strategies For effective weight management in-the only information available is from (24-26). tervention, a patient ideally would bethe referring physician; therefore the EAL Recommendation “Esti- assessed by a multidisciplinary team,depth and exploration required to ad- mated energy needs should be based including a physician, RD, exerciseequately assess nutritional status on [resting metabolic rate]. If possi- physiologist, and a behavior thera-and related factors will be an issue of ble, [resting metabolic rate] should be pist. Through the team approach, is-professional judgment and may ex- measured (eg, indirect calorimetry). sues such as nutrition, physical activ-tend to subsequent consultations. Nu- If [resting metabolic rate] cannot be ity, and change in eating behavior cantritional adequacy established from measured, then the Mifflin-St Jeor be coordinated. Although this ap-dietary history and food intake equation using actual weight is the proach may be a gold standard, thererecords coupled with anthropometric most accurate for estimating [resting are many barriers such as the in-and biochemical measures provide metabolic rate] for overweight and creased cost of a multidisciplinarybaseline data. The possible multiple obese individuals” (Rating: Strong, team, the lack of third-party reim-components of a comprehensive inter- Conditional) (11). The Mifflin-St bursement, and the absence of expe-view are summarized in the Figure. Jeor equations are: rienced weight management health The ADA adult weight manage- care professionals. However, once ament guidelines advise resting en- Man: Basal Metabolic Rate (BMR) primary care physician has deter-ergy expenditure measurement as (10 weight in kilograms) (6.25 mined that a client would benefit332 February 2009 Volume 109 Number 2
  4. 4. from the expertise of a team ap- sodic signaling primarily from the itself, presents confounding factors.proach, the appropriate referrals can gut. The long-term signaling uses For example, under-reporting of en-be made. Most commonly, RDs as- hormones such as leptin and insulin ergy intake is persistently prevalentsume a leadership role to design and to act as key drivers for initiating food in dietary surveys and appears to beactivate the intervention strategy intake. Generated in response to an greater in overweight vs normal-developed by the multidisciplinary eating episode, the episodic signaling weight people (29). In addition, littleteam or in collaboration with the re- system is activated from the gastroin- is understood regarding the physiol-ferring medical provider. The active testinal tract and uses hormones such ogy of eating behaviors in people withrole ADA is now taking in establish- as ghrelin, cholescystokinin, gluca- severe obesity, people following a re-ing evidence-based guidelines will gon-like peptide, and peptide YY, cent weight loss, or the influence ofcontinue to modify assessment prac- among others. These episodic signals physical activity on the eating behav-tices. rise and fall in harmony with eating ior systems. Nutrition assessment is an ongo- patterns. The interaction betweening, dynamic process that involves these two sets of homeostatic signalsnot only initial data collection, but reflects the brain’s recognition of the Diet Compositionalso continual reassessment and current dynamic state of energy A low-fat, reduced-energy diet is theanalysis. Assessment provides the stores and the changing nutrient flow best studied weight-loss dietaryfoundation for the nutrition diagno- derived from eating. This central reg- strategy and is most frequently rec-sis, which is the next step of the Nu- ulation of energy balance tunes hun- ommended by governing health au-trition Care Process. ger and fullness sensations that ac- thorities (11,17,30). Fat is the most company eating behaviors. energy-dense macronutrient but is Unlike the central nervous regula- known to have a weak effect on bothREGULATION OF FOOD INTAKE tion of the homeostatic system (located satiation and satiety (31). These at-A negative energy balance is the most primarily in the arcuate nucleus of tributes make fat a useful target forimportant factor affecting weight loss the hypothalamus), a cortico-limbic reducing energy intake. Because dia-amount and rate. The first recom- neural network regulates the hedo- betes and cardiovascular disease aremendation in obesity treatment is nic governance of food intake. This frequent comorbidities of obesity, re-usually a reduction in energy intake: neural network (involving signals such ducing the dietary saturated andA reduction of 500 to 1,000 kcal/day is as endocannabinoids, serotonin, and trans-fatty acid content is also recom-advised to achieve a 1 to 2 lb weight dopamine) deals with the cognitive, mended (30). The effectiveness of low-loss per week (11,12). Dietary energy motivational, and emotional aspects of fat, low-energy diets in combinationreduction strategies may vary from a food intake (eg, perceived pleasantness, with lifestyle counseling and activityfocus solely on energy (ie, “calorie liking, and wanting). This system rep- has been demonstrated in recent mul-counting”), macronutrient composi- resents the main interface with the ticenter clinical trials where, in addi-tion and/or energy density, or a com- external environment as, in the ab- tion to 5% to 10% weight loss, thebination of energy and macronutrient sence of a depletion signal, the initia- reduction or prevention of comorbidi-composition along with form consid- tion of an eating episode often starts ties such as diabetes and/or hyperten-erations such as consistency (eg, meal as a cognitive decision from the cortex sion has also occurred (32-35).replacements, very-low-energy diets). (28). Palatability, via this system, is a Frequently, individuals reduce theIn addition, strategies have included very powerful determinant of food in- carbohydrate content of their diet as achanges to meal frequency, meal tim- take and inappropriate sensitization weight loss strategy. As glycogening (eg, breakfast) and guidance on of the hedonic network likely leads to stores are depleted in response to low-food portions. To evaluate the evi- weight gain. However, the hedonic carbohydrate intake, the resultant di-dence supporting these proposed system is less well-studied than its uresis produces an initial dramaticstrategies, it is necessary to first re- homeostatic counterpart and much weight loss. On very-low-carbohy-view what is known about the regula- more research is required to fully un- drate diets (eg, 20 g/day) the bodytion of eating behavior in human be- derstand the interactions of these two produces ketones to sustain fuel uti-ings. systems. lization in the brain, which may in Eating is a behavior that links the The complexity of eating behavior turn help with diet adherence by de-external physical environment with makes it difficult to completely eluci- creasing hunger (36). Individuals as-an individual’s internal physiologic date the role of any one of the energy signed to the ad libitum low-carbohy-processes (27). Two distinct internal reduction strategies. Whereas a ran- drate diet in recent randomizedsystems govern food intake: the ho- domized study with high dietary con- controlled trials lost more weight at 6meostatic system and the hedonic trol helps to evaluate affects of energy months than individuals assigned tosystem. Although both systems are reduction on weight loss per se, longi- the low-fat, reduced-energy diet, butregulated centrally, they do not ap- tudinal studies in free-living individ- this difference was no longer signifi-pear to be integrated. Reduced appe- uals (albeit with less dietary control) cant at 12 months (11,37,38). Con-tite control may be due to either dis- are also required to evaluate the cerns regarding an increase in cardio-turbance in homeostatic pathways or other system components. Unfortu- vascular risks with low-carbohydrateto inappropriate sensitization of the nately, studies in free-living individ- diets do not appear to be as problem-hedonic system. The homeostatic sys- uals (either longitudinal or cross-sec- atic as first thought (37).tem comprises both long-term signal- tional) often have to rely on self- EAL Recommendation “An indi-ing from the adipose tissue and epi- reported food intake, which, in of vidualized reduced calorie diet is the February 2009 ● Journal of the AMERICAN DIETETIC ASSOCIATION 333
  5. 5. basis of the dietary component of a since it is has not been shown to be pears to be an important weight gaincomprehensive weight management effective in these areas” (Rating: prevention strategy for everybody (re-program. Reducing dietary fat and/or Strong, Imperative) (11). gardless of weight) as marketplacecarbohydrates is a practical way to EAL Recommendation “In order food and drink portions now exceedcreate a caloric deficit of 500 to 1,000 to meet current nutritional recom- standard serving sizes by a factor ofkcal below estimated energy needs mendations, incorporate 3-4 servings at least twofold (39). Portion distor-and should result in a weight loss of 1 of low-fat dairy foods a day as part of tion is a new term created to describeto 2 lb per week” (Rating: Strong, the diet component of a comprehen- this perception of large portions asImperative) (11). sive weight management program. appropriate amounts to eat at a single EAL Recommendation “Having Research suggests that calcium in- eating occasion. This distortion is re-patients focus on reducing carbohy- take lower than the recommended inforced by packaging, dinnerware,drates rather than reducing calories level is associated with increased and serving utensils that have alsoand/or fat may be a short-term strat- body weight. However, the effect of increased in size (40).egy for some individuals. Research in- dairy and/or calcium at or above rec- Most of the evidence supporting thedicates that focusing on reducing car- ommended levels on weight manage- value of portion control comes frombohydrate intake ( 35% of kcal from ment is unclear” (Rating: Fair, Im- studies in normal-weight and/or over-carbohydrates) results in reduced en- perative) (11). weight subjects using experimentalergy intake. Consumption of a low- The debate regarding the optimal paradigms such as differences in serv-carbohydrate diet is associated with a macronutrient content of a reduced- ing containers, self-refilling bowls, andgreater weight and fat loss than tra- energy diet has emphasized the diffi- self-service vs preserved food itemsditional reduced-calorie diets during culty individuals have in following (11). These studies show that by in-the first 6 months, but these differ- any weight loss regimen. Whether creasing portion sizes, energy intakeences are not significant after 1 year” randomized to a low-fat or a low-car- during an eating occasion is increased(Rating: Fair, Conditional) (11). bohydrate diet, study completion but is not compensated for by a de- The EAL also notes that safety has rates at 1 year are typically low for crease in intake later in the day.not been evaluated for long-term, ex- both interventions (37). It is likely Three randomized controlled trialstreme restrictions of carbohydrates that factors from both the homeo- showed weight loss in participants( 35% of energy from carbohydrates) static as well as the hedonic systems using specific portion control strate-and specifically recommends that influence an individual’s ability to ad- gies of frozen entrees (vs self-selectedpractitioners use caution in suggest- here to any type of weight loss diet. diet based on the Food Guide Pyra-ing a low-carbohydrate diet for even We need to better understand the fac- mid) (11), use of cereal to replaceshort-term use in patients with osteo- tors that influence individual adher- usual evening snacks (11), and aporosis, kidney disease, or in patients ence as well as study attrition rates in plate-method education tool (41). Al-with increased low-density lipopro- general, because these two parame- though the concept of portion controltein cholesterol (11). ters affect interpretation of trial out- is universal in most weight manage- comes. ment programs, the overall strength of the evidence for portion control to Portion distortion is a reduce energy intake and produce Portion Control weight loss is graded as fair (11). new term created to RDs typically recommend portion More research is needed to determine describe this control to weight loss clients with the the effectiveness of specific portion goal of reducing the energy load of control strategies on body weight reg- perception of large consumed foods. Strategies may in- ulation especially for people in differ- portions as clude providing information on the ent physiological states (eg, post- energy content of regularly consumed weight loss [ie, to prevent a weight appropriate amounts foods (eg, energy content of 1⁄2 c vs one regain] or people with severe obesity). to eat at a single bowl of ice cream), use of premea- EAL Recommendation “Portion sured foods (eg, frozen entrees, 100- control should be included as part of a eating occasion. kcal snack packs), replacing higher comprehensive weight management energy-density foods with lower ener- program. Portion control at meals Additional dietary components gy-density foods (eg, cereal with milk and snacks results in reduced energythought to influence weight (ie, low for an evening snack), and/or reduc- intake and weight loss” (Rating:glycemic index diets and diets high in ing the energy density of foods (eg, Fair, Imperative) (11).calcium) were evaluated. In both in- increasing vegetable content of entréestances, low glycemic index foods and items). These strategies may affect ei-low-fat dairy foods can be incorpo- ther the homeostatic system (eg, re- Eating Frequencyrated but are not essential for diets duced portions may be more or less Many RDs encourage weight lossappropriate for weight management. satiating depending on the strategy clients to avoid skipping breakfast EAL Recommendation “A low used) and/or hedonic system (eg, cog- and to have a regular meal pattern.glycemic index diet is not recom- nitive decisions to choose one food This advice is prompted by a con-mended for weight loss or weight over another possibly more palatable cern for compromised nutrient in-maintenance as part of a comprehen- food) that govern eating behavior. Ef- take if breakfast is not consumed (eg,sive weight management program, fectively reducing portion sizes ap- decreased calcium and fiber intake),334 February 2009 Volume 109 Number 2
  6. 6. that an erratic schedule leads to poor vs nonbreakfast consumers. Three a weight maintenance phase of theirfood choices from available foods that cross-sectional studies show an asso- evaluation and reported a greater ef-are energy dense but nutrient poor ciation between skipping breakfast fect of one meal replacement per day(eg, vending machines, office candy and an increased prevalence or risk of over conventional diet for mainte-jars, and fast-food restaurants), as obesity (11). However, the association nance of a weight loss (11). Individu-well as concern that evening energy may vary depending on the breakfast als adhering to structured meal re-consumption is more likely to lead to content (eg, high-fat breakfast con- placement plans lose more weight atweight gain. Generically prescribing sumers are associated with higher both 12 weeks ( 7% vs 4% of initiala certain meal frequency or advocat- BMIs than high-fiber breakfast con- body weight) and 1 year ( 7% to 8%ing the inclusion of breakfast as a sumers) and sex (eg, the association vs 3% to 7%) than individuals follow-specific weight loss (or prevention of between breakfast consumption and a ing a conventional diet plan, withweight gain) strategy must be based BMI 25 is significant for women but 1-year dropout rates for the struc-on an understanding of the evidence not for men) (11). In one randomized tured meal replacement plan signifi-of whether the pattern of meal con- controlled trial, the habitual break- cantly less than the conventional dietsumption affects energy intake and fast-eating habits of the study par- plan (47% vs 64%; P 0.001) (11). Tothereby weight loss. Unfortunately ticipants interacted with treatment date, structured meal replacementthe evidence is inconsistent as the re- assignment (breakfast vs no-break- plans and weight loss efficacy in se-search on eating frequency patterns fast treatment) to influence the verely obese individuals or as ais not extensive with no randomized measured weight change (11). Fur- weight gain prevention strategy havecontrolled studies. A number of cross- ther research on the relationship be- not been sufficiently studied.sectional studies show equivocal find- tween breakfast and body weight There is concern that this strategyings on the association of eating fre- regulation is needed. may mean an over-reliance on artifi-quency to body weight regulation Although the research does not yet cial nutrients and may prevent cli-(11). Limitations in study design or support making absolute meal fre- ents from learning how to select ap-inconsistency in methodology may be quency or breakfast recommenda- propriately from typical conventionalthe reason for this lack of clarity and tions for optimizing body weight con- food choices. These specific concernsfair evidence grade (11). These stud- trol, it is important that clinical have not been systematically studied.ies have relied on self-reported intake judgment is used when guiding cli- However, RDs have a role in advisingbut as yet it is not clear where the ents. Helping a client to find a meal clients utilizing meal replacementsunder-reporting of energy intake (es- pattern that prevents the times when on how to optimize the overall nutri-pecially prevalent among obese par- high hunger coincides with an envi- ent content of their diet by carefulticipants) comes from (ie, mispercep- ronment of high-energy food choices selection of the conventional foodstion and/or misreporting of meal seems pertinent. that make up the non–meal-replace-portions, omission of eating occasions, EAL Recommendation “Total ca- ment portion of the weight loss plan.or a combination of both). The defini- loric intake should be distributed EAL Recommendation “For peo-tion of an eating occasion is often in- throughout the day, with the con- ple who have difficulty with self selec-consistent between studies (eg, one sumption of four to five meals/snacks tion and/or portion control, meal re-study used 50 kcal separated from an- per day including breakfast. Con- placements (eg, liquid meals, mealother eating episode by 15 minutes sumption of greater energy intake bars, or calorie-controlled packagedwhereas another study used main during the day may be preferable to meals) may be used as part of the dietmeal, beverage meal, light meal, or evening consumption” (Rating: Fair, component of a comprehensive weightsnack categories) (11). Finally, the Imperative) (11). management program. Substitutingcharacteristics of people who routinely one or two daily meals or snacks withhave a regular vs irregular meal pat- meal replacements is a successfultern are still unknown, making it diffi- Meal Replacements weight loss and weight maintenancecult to understand the influence of eat- Choosing a low-energy, nutritious strategy” (Rating: Strong, Condi-ing frequency per se vs other personal diet in an environment that provides tional) (11).attributes (eg, insulin levels, ghrelin a surplus of palatable, energy-dense,levels, age, daily work schedule, and nutrient-poor food choices can easilyroutine exercise habits). overwhelm anyone trying to lose Very-Low-Energy Diets Breakfast consumption possibly weight. Meal replacements, contain- Unlike meal replacements, which areplays a role in weight management ing a known energy and macronutri- designed to replace only one or twothrough an influence on appetite con- ent content, are a useful strategy to meals per day, a very-low-energy diettrol, dietary quality, and metabolism eliminate problematic food choices or is designed to be the only food source(42). Like the research on eating fre- complex meal planning while trying during active weight loss. A very-low-quency, the research on the affect to attain a 500 to 1,000 kcal/day en- energy diet is typically a liquid formu-of breakfast consumption on body ergy deficit. Several studies compar- lation that supplies about 800 kcal (orweight regulation is primarily fo- ing isocaloric diets have shown equiv- 6 to 10 kcal/kg) or less per day, iscused on cross-sectional studies and alent or greater weight loss efficacy enriched with high biologic value pro-is confounded by the same factors of with structured meal replacement tein and provides at least 100% of thereliance on self-report, definition of plans compared to reduced-energy Daily Value of essential vitamins andwhat constitutes a breakfast, and diet treatments (11). Three of these minerals. The purpose of using alack of characterization of breakfast randomized controlled trials included very-low-energy diet is to quickly February 2009 ● Journal of the AMERICAN DIETETIC ASSOCIATION 335
  7. 7. achieve a large weight loss while pro- in significant weight loss” (Grade cluded in obesity treatment pro-viding adequate nutrition and pre- I Good) (11). grams.serving lean body mass as much as EAL Conclusion “Adherence to a Although its influence on weight losspossible. Medical monitoring is neces- very-low-calorie results in lower calo- may be minimal, physical activity ap-sary during the rapid weight loss rie intakes and therefore significantly pears to be crucial in the prevention ofphase and the medical risk makes a greater initial weight loss than re- weight regain. Many correlation stud-very-low-energy diet inappropriate duced-calorie diets” (Grade I Good) ies show a strong association betweenfor individuals with a BMI 30. Al- (11). physical activity at follow-up and main-though there is good evidence that EAL Conclusion “While adher- tenance of a weight loss (45,48,49).adherence to a very-low-energy diet ence to a very-low-calorie results in Doubly-labeled water studies indicateresults in significant weight loss of 15 significant initial weight loss, studies that physical activity in the range ofto 5% of initial body weight over 12 to report varying levels of weight regain 11 to 12 kcal/kg/day maybe necessary16 weeks, maintenance of that weight based on differences in weight main- to prevent weight regain following aloss is problematic (11,43). In 1998, tenance strategies” (Grade I Good) weight loss (50). Data from the Na-the NHLBI expert panel recom- (11). tional Weight Control Registry alsomended against the use of very-low- indicate that a high level of dailyenergy diets. The decision was based physical activity may be necessary toon studies showing no differences in Physical Activity prevent weight regain (51). The Na-long-term weight losses between very- An energy deficit of 500 to 1,000 tional Weight Control Registry is alow-energy diets and low-energy diets kcal/d is necessary to achieve a 1- to registry of more than 3,000 individu-primarily because of greater weight 2-lb weight loss per week (11). Pro- als who have successfully maintainedregain with very-low-energy diets ducing this energy deficit through at least a 30-lb weight loss for a min-(12). Although there have been many physical activity alone is extremely imum of 1 year. These individuals re-studies evaluating the long-term difficult for most adults. Few studies port using a variety of methods to losemaintenance of weight loss following have used a large enough physical ac- weight initially, but more than 90%very-low-energy diets, the majority tivity “dose” to achieve a 5% weight report exercise as crucial to theirhave been case-series with no direct loss using a physical activity inter- long-term weight-loss maintenance.comparison with a low-energy diet vention alone (45). Weight-loss stud- They report expending, on average,culminating in equivocal results (11). ies have shown only small reductions 2,682 kcal per week in exercise, anA recent meta-analysis was con- in body weight with physical activity energy equivalent of walking 4 milesducted evaluating six randomized treatment compared to no-treatment 7 days a week (51). It has been pro-controlled trials that each included control groups (45). However, the posed that high levels of physical ac-very-low-energy diet and low-energy magnitude of weight change due to tivity allows for a post-reduced indi-diet comparisons for short-term and physical activity is additive to that vidual to sustain a lowered energy-long-term (at least 1 year follow-up) associated with a dietary intervention balance level without overly restrictingweight loss (43). Despite significantly achieving energy restriction (45). The food intake (52).greater short-term weight loss with influence of physical activity on Specific physical activity recom-very-low-energy diets (16.1% 1.6% weight loss depends on the ability of mendations were included for thevs 9.7% 2.4%; P 0.0001), the weight an individual to engage in adequate first time in the 2005 Dietary Guide-loss was similar between very-low-en- levels of exercise such that the energy lines (17). These recommendations in-ergy diets and low-energy diets for cost of exercise is greater than typical cluded three categories related tolong-term weight loss (6.3% 3.2% vs fluctuations or compensatory changes weight management goals. The first5.0% 4.0%; P 0.2) (43). Overall at- in energy intake. Depending on body recommendation, to reduce the risk oftrition in the six studies was not dif- size, fitness level, and exercise inten- chronic disease in adulthood, is for 30ferent between the very-low-energy sity, an individual may burn an addi- minutes of moderate-intensity physi-diet and low-energy diet groups. tional 1,000 kcal per week by exercis- cal activity on most days of the week. The use of very-low-energy diets ing 30 minutes 5 days a week. In The second recommendation, to helphas been increasingly prescribed be- comparison, an extra 1,000 kcal could manage body weight and preventfore bariatric surgery to reduce over- easily be consumed by miscalculating weight gain in adulthood, is to engageall surgical risk in patients with se- portion sizes and/or a couple of extra in 60 minutes of moderate- to vigor-vere obesity. There is indication that snacks or beverages. However, de- ous-intensity activity on most days ofthe use of very-low-energy diets for at spite its modest impact on weight the week. Finally, to prevent weightleast 2 weeks reduces liver size al- loss, physical activity is important for regain after weight loss, engage in 60though up to 6 weeks may be more improving health-related outcomes to 90 minutes of daily moderate-in-ideal for clinically significant de- related to many obesity comorbidities tensity physical activity while not ex-creases in abdominal adiposity (44). (eg, heart disease, cancer, and diabe- ceeding energy requirements. TheFurther research is necessary to eval- tes) (45,46) although additional re- first Federal Physical Activity Guide-uate the efficacy of this strategy for search is required to understand this lines for Americans were issued insurgery candidates with severe obe- relationship in individuals with BMI late 2008 (45). These guidelines pro-sity. 40. Regular physical activity is also vided a comprehensive summary of EAL Conclusion “Adherence to a associated with a lower risk of death the scientific evidence for the healthvery-low-calorie diet, defined as 800 regardless of BMI (47). Therefore, it is benefits of physical activity and havekcal or 6 to 10 kcal/kg or less, results important that physical activity is in- similar recommendations to the 2005336 February 2009 Volume 109 Number 2
  8. 8. Dietary Guidelines—all adults should up, small study sizes, as well as in- ioral package (ie, self-monitoring,avoid inactivity and health benefits ability to account for the influence of stimulus control, problem solving, so-(including weight control benefits) in- additional study components such as cial support, and cognitive restructur-crease as physical activity increases step diaries and physical activity ing) are in changing behavior and(45). Unlike the recommendations in counseling. In addition, as the mean promoting weight loss in adults.the 2005 Dietary Guidelines (17), the preintervention BMI of study partici- Cognitive Behavioral Therapy and WeightPhysical Activity Guidelines make pants was 30 3.4, the efficacy of pe- Loss. A limited number of studiesrecommendations in weekly vs daily dometer use in people with severe have evaluated the intermediate (6 todoses: at least the equivalent of 150 obesity (BMI 40) was not evaluated. 12 months) effectiveness of cognitiveminutes/week of moderate-intensity Use of pedometers in severely obese in- behavioral therapy on weight loss.aerobic physical activity for substan- dividuals deserves further research. EAL Conclusion “One neutraltial health benefits and 300 minutes/ quality, 6-month randomized con-week of moderate-intensity physical Behavioral Interventions trolled trial (86 obese adults) providesactivity for more extensive health ben- evidence that intermediate durationefits (45). Acknowledging the great in- Historically, cognitive behavioral treat- ment of obesity developed from the be- (6-12 months) behavioral therapy andterindividual variability that exists behavioral therapy combined with awith physical activity and achieving/ lief that obesity was the result of mal- adaptive eating and exercise habits, personalized system of skill acquisi-maintaining a healthful weight, these tion targeting weight loss is more ef- which could be corrected by the appli-guidelines suggested that many people fective than weight loss education cation of learning principles (55). To-may need more than the equivalent of alone in facilitating weight loss, de- day, it is understood that body weight150 minutes/week of moderate-inten- creasing both total energy intake and is affected by factors other than be-sity physical activity to maintain their percent of calories from fat, and in- havior, including genetic, metabolic,weight and more than 300 minutes/ creasing physical activity” (Grade and hormonal influences (56,57). Al-week to meet weight-control goals (45). though behavior modification is only III Limited) (11).RDs have a role in reinforcing these one piece of the puzzle, behavior ther- Compared to patients with obesityrecommendations that will help clients apy can help individuals develop a set receiving the weight-loss educationalachieve appropriate physical activity of skills to achieve a more healthful program (ie, 6 monthly education ses-goals through the different phases of weight (34,58,59). sions on nutrition, behavioral strate-weight management (ie, prevention of gies for changing eating and exerciseweight gain, weight loss, and sustain- What Is Cognitive Behavioral Therapy? Cog- habits, and guidelines for increasinging a weight loss). nitive behavioral therapy is based physical activity), patients with obe- Pedometers and step counters are largely on principles of classical con-frequently used to promote daily sity who either received standard be- ditioning, which assert that eating isphysical activity. These small, rela- often prompted by antecedent events havior therapy (ie, 25 weekly sessionstively inexpensive devices are worn (ie, cues) that become strongly linked on self-monitoring, goal setting, stim-at the hip and track the number of to food intake (55). Cognitive behav- ulus control, and cognitive restructur-steps taken per day. Individuals ioral therapy helps patients identify ing) or behavior therapy plus person-wearing these devices can track their cues that trigger inappropriate eating alized skill acquisition (ie, behaviordaily variability in steps and/or com- (and activity) behaviors and learn therapy plus reinforcement [mone-pare daily steps against a prescribed new responses to them (60). Treat- tary rewards] contingent on individ-step goal (both behaviors that may ment also seeks to reinforce (or re- ual mastery of specific skills related topromote problem-solving to prevent ward) the adoption of positive behav- eating and exercise behaviors) lost sig-unnecessarily low step days). 10,000 iors. Cognitive behavioral therapy nificantly more weight at 6 months.steps per day is an appropriate daily has several distinguishing character- Small randomized trials evaluatingstep goal consistent with the 30 min- istics (61): it is goal-directed (measur- the effects of cognitive behavioralutes of moderate-intensity physical able outcomes), process-oriented (helps therapy on weight loss over 2 yearsactivity recommendation of the 2005 people decide how to change), and ad- have also shown positive effects onDietary Guidelines (53); however, a vocates small rather than large weight control though weight gain ishigher step goal would be necessary changes. The behavior change process typically observed over time.to either produce weight loss by phys- is facilitated through the use of a va- EAL Conclusion “One neutralical activity alone or to maintain a riety of problem-solving tools and quasi-experimental (84 participantsweight loss. A recent meta-analysis of usually includes multiple components received behavior therapy) and two26 studies (eight randomized con- such as nutrition education, keeping positive randomized controlled trialstrolled trials and 18 observational food and activity records (ie, self-mon- (65 participants received behaviorstudies) evaluating pedometer use itoring), controlling cues associated therapy and a very-low-calorie diet)showed that physical activity in pe- with eating (ie, stimulus control), evaluated behavior therapy as a com-dometer users increased 26.9% over problem solving, cognitive restructur- ponent of a weight-loss program ofbaseline (54). Having a step goal, ing, and physical activity (60). These long-term duration ( 12 months). Be-such as 10,000 steps per day, was components comprise the behavioral havior therapy was not always thean important predictor of increased package. ADA’s Nutrition Counseling variable of randomization. Partici-physical activity (P 0.001) (54). work group is currently reviewing the pants receiving behavior therapy lostNoted limitations of this meta-analy- evidence to determine how effective weight at the conclusion of treat-sis were the lack of long-term follow individual components of the behav- ments. Upon follow-up there was February 2009 ● Journal of the AMERICAN DIETETIC ASSOCIATION 337
  9. 9. some weight regain but participants ings were observed in the Look the results of lifestyle interventionremained at a lower weight than AHEAD study, which compared the studies can be replicated in the realbaseline. Studies that included a effectiveness of a behavioral interven- world, researchers designed the Goodvery-low-calorie diet to initiate rapid tion program and enhanced usual Ageing in Lahti Region Program, ainitial weight loss, combined with be- care (ie, diabetes support and educa- lifestyle implementation study de-havior therapy, also appeared to pro- tion) on weight loss and the preven- signed for primary health care set-duce long-term weight loss. [Note: tion of cardiovascular disease in indi- tings (65). Although the outcomesThis is not a statement recommend- viduals with type 2 diabetes (32). Not were less robust than more intensiveing very-low-energy diets or suggest- only did individuals in the behavioral efficacy studies, favorable lifestyleing that very-low-energy diets are intervention group lose more weight changes were reported and weightmore beneficial than low-energy di- at 1 year, they also observed greater gain was prevented, suggesting onets.]” (Grade II Fair) (11). reductions in medication use, fasting overall positive effect of lifestyle A number of large randomized glucose, hemoglobin A1c, blood pres- counseling in real-life settings. Addi-studies examined the effects of cogni- sure, triglyceride levels, and greater tional studies are needed to deter-tive behavioral therapy on diabetes increases in high-density lipoprotein mine the effectiveness of clinic-basedand cardiovascular disease risk. levels. behavioral treatment on weight gainGiven the beneficial effect of weight The Finnish Diabetes Prevention prevention, weight loss, and weightreduction on these disease states, study also compared the efficacy of maintenance.weight loss is often an outcome that is lifestyle modification and usual care Findings from these studies sug-evaluated. The typical design of many in individuals at high risk for type 2 gest that cognitive behavioral ther-behavioral studies is group meetings diabetes (58). This study was ended apy combined with a healthful dietweekly for the initial treatment phase early due to clear differences in out- and physical activity results in signif-(approximately 3 to 6 months), bi- comes (ie, body weight, plasma glu- icant weight loss in the short-term.weekly (every other week) meetings cose, risk of type 2 diabetes) between Individuals lose approximately 8% tofor the maintenance phase (6 to 12 intervention and control groups. The 11% of their initial body weight dur-months), and monthly or bimonthly extent to which lifestyle changes and ing the treatment phase (24 to 32for the later phases of the study (12 to risk reduction remained after discon- weeks) but slowly regain weight over24 months) (33,61-64). tinuation of active counseling was time (ie, approximately 4% to 8% and The PREMIER, Diabetes Preven- studied in a follow-up to the Finnish 2% to 4% of their initial body weighttion Program, Finnish Diabetes Pre- Diabetes Prevention study (32). The after 48 and 72 weeks, respectively)vention, and Look AHEAD studies incidence of diabetes and body weight (66-69). Five years after treatment,are examples of large, multicenter, was examined for a total of 7 years. 50% or more of patients have re-randomized studies that demonstrate The relative risk for developing type 2 turned to their baseline weight (68);the influence of behavior modification diabetes remained significantly less however, there is some evidence toon weight loss, diabetes, and cardio- in individuals who were in the life- suggest that individuals who partici-vascular disease risk (33-35,58,59). style intervention group and was re- pate in maintenance therapy (twice aParticipants in the PREMIER study lated to the success in maintaining month for 1 year) after initial treat-were randomly assigned to either a weight loss; eating a low-fat, high-fi- ment maintain most of their weightcontrol group (single advice-giving ber diet; and engaging in physical ac- loss at follow-up (ie, approximatelysession) or one of two behavior modi- tivity. These findings are encouraging 10% and 8% of their initial bodyfication intervention groups, which but behavior therapy’s effectiveness weight after 48 and 72 weeks, respec-differed in diet prescription (35). Sig- for long-term weight maintenance tively) (69-73).nificantly greater weight losses were has not been shown in the absence ofobserved in the intervention groups continued behavioral intervention Strategies for Augmenting Outcomes. Al-compared to the control group at 6 (12). Long-term follow-up of patients though cognitive behavioral treat-months. There were no significant dif- undergoing behavior therapy shows a ment provides individuals with a setferences in weight loss between the return to baseline weight in the great of skills to handle barriers to eatingintervention groups, suggesting that majority of subjects in the absence of healthfully and being active, over-behavior modification had a stronger continued behavioral intervention (12). coming barriers is a difficult endeavorinfluence on weight loss than the pre- Although these studies have limita- in a fast-paced environment that en-scribed method of energy restriction. tions (ie, participant-clinician contact courages overconsumption of energy- The Diabetes Prevention Program and instruction was greater in the in- dense, palatable, low-cost foods andshowed that intensive behavior mod- tervention groups; therefore, these promotes energy-saving devices (8). Aification is not only more efficacious in studies do not simulate treatment in healthful lifestyle requires significantproducing weight loss and improving the real world because of their high planning, proficiency in making ap-health than general recommenda- intensity and frequency), these well- propriate choices and estimating por-tions but also more efficacious than designed efficacy studies show that tion sizes, and diligence in monitoringpharmacotherapy (33). Participants behavioral treatment in combination energy intake and activity, all ofin the intensive lifestyle group lost with low-energy, low-fat diets have which take time to develop and main-significantly more weight and also positive effects on weight control tain. As such, strategies for simplify-had a significantly lower incidence of and, more importantly, on comorbid ing and making this process moretype 2 diabetes than those taking conditions. practical by providing structure andmetformin or placebo. Similar find- As a means to determine whether reducing time spent in meal planning338 February 2009 Volume 109 Number 2
  10. 10. and decision making (eg, meal re- per year over placebo (74). Hyperten- logues, and adiponectin; gastroin-placements as described above) may sion and increased heart rate are po- testinal-neural pathway agents tobe useful for some people. tential complications so it is contrain- increase cholecystokin or decrease EAL Recommendation “A com- dicated for individuals with known ghrelin activity; enhancers of energyprehensive weight management pro- heart disease, uncontrolled hyperten- expenditure, UCP2 and UCP3 uncou-gram should make maximum use of sion, heart failure, stroke, and ar- pling proteins, and thyroid receptorthe multiple strategies for cognitive rhythmias. Sibutramine is also con- agonists; and inhibitors of fatty acidbehavioral therapy (ie, self-monitor- traindicated with monoamine oxidase synthesis (82).ing, stress management, stimulus inhibitors and other serotonin uptake Leptin has undergone phase twocontrol, problem solving, contingency inhibitors, which include medications testing, but data at this time do notmanagement, cognitive restructur- for depression and migraine (76). The indicate leptin has the potential to being, and social support). Cognitive be- evaluation of the reported cardiovas- clinically useful for the modification ofhavior therapy in addition to diet and cular effects has determined that the weight status (83). Both Axokine (84)physical activity leads to additional risk-benefit ratio remains favorable and rimonabant (85,86) are in stageweight loss. Continued behavioral in- (77). three trials. Fenfluramine, alone or interventions may be necessary to pre- Orlistat. Orlistat is a pancreatic lipase combination with phentermine, pro-vent a return to baseline weight” inhibitor that inhibits the absorption duced effective weight loss but serious(Rating: Strong, Imperative) (11). of up to 30% of dietary fat (78). In the side effects resulted (87). This volun- Further research is needed to iden- 22 studies that reported 12-month tary medication withdrawal slowedtify the most potent components of data, those treated with orlistat lost effort for the use of combined medica-the behavior modification package, as 2.89 kg more than those on placebo. tions. Currently three trials of com-well as additional interventions (eg, Steatorrhea, bloating and distension, bined medications are in progress:body image therapy) and counseling Qnexa (topiramate phentermine) and anal leakage are potential sidetechniques (eg, motivational inter- (Vivus, Inc, Mountainview, CA), Ex- effects if dietary fat is not restricted,viewing) that might be added to assist calia (bupropion zonisamide) (Orexi- and one must be alert for possible fat-patients in making behavior change gen Therapeutics, La Jolla, CA [now soluble vitamin deficiencies. With theand to improve efficacy, especially in long-term safety record that has been called Empatic]), and Contrave (bu-the long term. It is possible that there achieved, orlistat has been approved propion naltrexone) (Orexigen Ther-is no single behavioral tool that works for over-the-counter sales at a re- apeutics, La Jolla, CA).best. Instead it may be more impor- duced dosage. Herbal preparations for weight losstant to match behavioral tools with Phentermine. Phentermine is a sympa- do not have standardized amounts ofeach individual’s unique set of char-acteristics. These are the type of thomimetic anorexogenic agent and active ingredients and harmful effectsquestions that need further attention the most widely prescribed weight have been reported (88,89). Certainand research. loss agent in the United States; how- over-the-counter preparations contain- ever, its use is approved by the FDA ing phenylpropanolamine (and related for only 3 months (79). In the six compounds) have no proven efficacyPharmacotherapy placebo-controlled studies available, for short- or long-term weight lossCurrent medications that have been published between 1975 and 1999, and are recalled because of the inci-approved by the Food and Drug Ad- the duration of treatment was be- dence of hemorrhagic stroke (90,91).ministration (FDA) for long-term tween 2 and 24 weeks with an aver- Ephedrine plus caffeine, and fluox-treatment of “clinically significant” age weight loss of 3.6 kg over pla- etine have been tested for weightobesity (BMI 30 or BMI 27 to 29 cebo. Side effects include insomnia, loss, but are not FDA-approved, andwith one or more obesity-related dis- constipation, and dry mouth. Inter- over-the-counter and herbal weightorders) include sibutramine and orl- mittent dosage in a randomized con- loss preparations are currently notistat. These two medications have trolled trial produced greater weight recommended (75).been evaluated in multiple random- loss than placebo (80). It has been shown that small reduc-ized controlled trials (44 for sibutra- The continued increase in the preva- tions in body weight (5%) can affectmine, 29 for orlistat). Medication lence of obesity speaks to the unmet obesity-related comorbidities (92). Ifcombined with lifestyle modification medical needs for safe and effective such reductions are achieved withis more effective than placebo with medications (81). Pharmacotherapy re- medications, data indicate that thoselifestyle modification in promoting search is currently focusing on: central medications be continued long-termweight loss in adults with overweight nervous system agents that affect neu- to maintain the change in weight sta-and obesity (74). The safety and effi- rotransmitters, including antidepres- tus (93). For those considering phar-cacy of the currently approved drug sants (bupropion), antiseizure agents macologic treatment for obesity, ittherapies have not been evaluated in (topiramate, zonisamide), and some should be noted that medications canchildren or older adults and there is dopamine antagonists; leptin/insulin/ lead to modest weight losses at 1 to 2limited information on adolescents central nervous system agents, in- years, but that data are not available(75). cluding leptin analogues or promoters, on long-term effectiveness and safetySibutramine. Sibutramine is a cen- ciliary neurotropic factor (Axokine, Re- (77).trally acting serotonin and adrenergic generon Pharmaceuticals, Tarrytown, When weight loss drugs are pre-reuptake inhibitor. Meta-analysis in- NY), neuropeptide-Y, and agouti–re- scribed they should be only as part ofdicates an average loss of 4.5 kg more lated peptides, -melanocyte ana- a comprehensive treatment plan in- February 2009 ● Journal of the AMERICAN DIETETIC ASSOCIATION 339
  11. 11. cluding behavior therapy, diet, and may be reduced by the placement of were reduced (105). In the Unitedphysical exercise (12). an adjustable band that allows only a States, a 7.1-year follow-up of pa- EAL Recommendation “FDA-ap- small amount of food to enter the tients with gastric bypass showed theproved weight loss medications may stomach or by the removal of part of group receiving surgery had long-be part of a comprehensive weight the stomach to produce a gastric term mortality reduced by 40% com-management program. RDs should sleeve. Gastric bypass operations, pared with the control populationcollaborate with other members of Roux-en-Y gastric bypass, and the ex- (106). Vogel and colleagues reported athe health care team regarding the tensive gastric bypass (biliopancre- reduction in predicted coronary heartuse of FDA-approved weight loss atic diversion, with duodenal switch) disease after bariatric surgery (107).medications for people who meet the create a small pouch by stapling or Their report emphasized the impor-NHLBI criteria. Research indicates removal of portions of the stomach, tance of significant and sustainedthat pharmacotherapy may enhance and also bypass the duodenum and weight loss as a powerful interventionweight loss in some overweight and other segments of the small intes- to reduce future rates of myocardialobese adults” (Rating: Strong, Im- tines, thus producing malabsorption infarction and death in the morbidlyperative) (11). along with restriction. These proce- obese. Data from the Canadian health dures have acceptable operative risk care system showed that long-term from 0.5% to 0.6% when performed by health care costs were reduced after aSurgery skilled surgeons (97-99). A fifth pro- bariatric procedure and the initialSurgery, with its inherent structural cedure, vertical banded gastroplasty, costs of surgery were amortized overchange, clearly has an advantage in has decreased in use because weight 3.5 years (108). Data are now avail-the long-term success of weight main- maintenance has been problematic able that with laparoscopic vs opentenance. It is reserved for patients (100,101). procedures, the duration of hospitaliza-with severe disease who have failed to Surgeon skill and a medical cen- tion has been decreased, wound compli-find less invasive interventions suc- ter’s bariatric surgery volume are im- cations are lower, post operative pa-cessful and are at high risk for obesity- portant factors in evaluating surgical tient pain is reduced, and bowelrelated morbidity and mortality. It is outcomes. The American Society of function normalizes more quickly (102,that group with morbid obesity that Metabolic and Bariatric Surgery and 108,109).has increased 400% from 1983 to the American College of Surgeons The effectiveness of different surgi-2000 (94). The patient selection crite- have established “Centers of Excel- cal procedures comparing both openrion established by the National In- lence” on the basis of hospital vol- and laparoscopically performed pro-stitutes of Health for surgery is cur- umes and surgical outcomes. Com- cedures on diverse populations byrently a BMI of 40. If weight-related pared with centers that had 50 surgeons with different levels of ex-comorbidities like diabetes, hyperten- cases, high volume centers with 100 pertise is difficult to interpret. Forsion, and sleep apnea are present, a cases per year had lower mortality, purposes of comparison, a range ofBMI between 35 and 40 may be con- shorter length of stay, lower overall weight loss defined as percentage ofsidered for a surgical procedure (12). complications, lower complications of excessive weight loss (change in BMI/Extending bariatric surgery to pa- medical care and lower costs (102). A nationwide, population-based sample original BMI 24) is commonly usedtients with BMIs of 30 to 34.9 whohave comorbid conditions that could reported 21.9% complications during (97). The effectiveness of the surgicalbe cured or markedly improved by the initial hospitalization, which in- procedures for weight loss range fromsubstantial weight loss is under re- creased to 39.6% during the first 180 47.5% excessive weight loss for theview at this time (95). days (103). The definition of a compli- adjustable gastric band, 61.6% for the All data indicate that for the mor- cation from the insurance records gastric bypass, 68.2% for gastro-bidly obese, bariatric surgery is the varied from an outpatient visit to a plasty, and 70% for the biliopancre-most effective therapy available for hospital readmission. Such data with atic diversion with or without theweight management and can result a broad interpretation of what is a duodenal switch. As noted above, gas-in improvement or resolution of the complication contrast sharply with troplasty is no longer frequently per-obesity-related comorbidities and data from the centers of excellence. A formed because a high rate of weightimproved quality of life (96). There- Canadian group has established that regain is documented. The sleeve pro-fore, it is important that RDs work- weight-loss surgery significantly de- cedure is increasing in use as a pri-ing in weight management are creases mortality, 0.68% compared mary procedure for high-risk andknowledgeable about the common with 6.17% in the nonoperated con- elderly patients or as an initial proce-surgical procedures, their mecha- trols as well as the development of dure for weight reduction to reducenisms of producing weight loss, as new health-related conditions in per- surgical risk before a second stage ofwell as the complications and con- sons with morbid obesity (104). Swed- a gastric bypass or the duodenalcerns. It is of note that surgical pro- ish investigators have recently pub- switch procedure. The excess weightcedures to promote weight loss are lished their 10.9-year follow-up of loss reported for the sleeve at 1 yearcontinually evolving. At the current operated vs nonoperated controls, approximates 46% (110-113). It is oftime there are four commonly used which clearly shows long-term weight note that surgery appears to rule overprocedures to assist weight loss by loss maintenance and decreased over- the genetic component of weight sta-restricting food intake and/or a com- all mortality in those having a bariat- tus in regard to weight loss responsesbination of restricting intake and pro- ric surgical procedure. Mortality from with surgery and weight mainte-ducing malabsorption. Food intake cardiovascular disease and cancer nance (114).340 February 2009 Volume 109 Number 2
  12. 12. improvements in insulin resistance loss need to chronically maintain a and inflammatory markers (119,120). lower energy intake or a combination of It is important that EAL Recommendation “Dieti- lowered energy intake and increased tians should collaborate with other energy expenditure— hence, the life- RDs working in members of the health care team re- long commitment portion of the posi- weight management garding the appropriateness of bariat- tion statement. However, as critical as ric surgery for people who have not it is for food and nutrition professionals are knowledgeable achieved weight loss goals with less in- to support their clients to prevent about the common vasive weight loss methods and who weight regain, it is not yet clear which meet the NHLBI criteria. Separate maintenance strategy is best pre- surgical procedures, ADA evidence-based guidelines are be- scribed for all individuals. their mechanisms of ing developed on nutrition care in bari- atric surgery” (Rating: Strong, Im- producing weight perative) (11). Responsibilities of Food and Nutrition loss, as well as the Professionals in Weight Management Many of the ideas expressed below complications and WEIGHT MAINTENANCE are not evidence-based but are the concerns. As demonstrated in the preceding sec- opinions of this writing group based tions, it is possible to lose weight us- on experience and knowledge in the ing a number of different strategies. field. Before surgery, patients should be However, weight loss is only one An individual’s body weight is de-fully evaluated by a multidisciplinary phase of the weight management con- termined by a combination of genetic,team, including but not limited to a tinuum. Prevention of weight gain (at metabolic, behavioral, environmen-medical doctor, psychiatrist, and an any BMI level) and prevention of tal, cultural, and socioeconomic influ-RD. The role of an RD is important weight regain (after a weight loss) an- ences. These diverse influences makeduring screening to evaluate weight chor either end of this continuum. treating individuals with overweighthistory, efforts to lose weight, food Each phase of the continuum possibly and obesity complex. Food and nutri-preferences, and food-related behav- requires a transition to a different setiors (ie, binge eating) to assist in tion professionals must understand of strategies and/or skill set. each of these aspects as they developelecting the optimal procedure for the The research on weight-loss main-patient. The patient must be in- a shared decision-making relation- tenance is relatively new and far from ship with clients. Food and nutritionformed of the lifestyle changes neces- conclusive with retrospective studiessary to decrease postoperative com- professionals should also be aware of of successful weight-loss maintainersplications and maintain weight loss. their own biases regarding individu- (121-125) and a small number of pro-Weight loss surgery is more effective als with this condition. In one study of spective studies (126-129). Issueswhen accompanied by pre- and post- RDs, 87% viewed individuals with confounding the evaluation of re-operative comprehensive therapy to obesity as self-indulgent and 32% in- search in this area include consensusmodify eating, smoking, and exercise dicated that individuals with obesity on amount of weight loss, weight lossbehavior. After surgery an RD may lacked willpower (135). These charac- duration, time between weight lossplay a vital role in promoting lifelong terizations could affect the style of and evaluation of weight mainte-health behavior change and adjust- nance, and minimum length of weight counseling for clients with obesity.ment to postsurgery dietary and sup- maintenance (130). Successful weight- Food and nutrition professionalsplementation requirements. Such loss maintenance may be an outcome should understand the importance ofadjunctive therapy increases the like- that is determined by multiple vari- weight gain prevention and the chal-lihood of long-term success and should ables, each contributing differently to lenge of weight loss maintenance tobe a standard component of surgical a successful outcome. Such variables effectively help their clients maintainweight management (115,116). All pro- might include factors impacting met- normal weight and sustain long-termcedures require lifelong medical fol- abolic as well as behavioral responses weight loss. Increased physical activ-low-up and monitoring to avoid and such as initial weight loss, comorbid ity also appears to be key in success-manage possible complications. conditions, presence of depression, ful weight loss maintenance (36). Liposuction is another form of sur- perception of weight loss success, RDs, with their understanding of en-gery with a focus on adipose tissue. level of self-monitoring, level of phys- ergy balance and energy expenditureIts purpose generally is cosmetic, to ical activity, type of intervention (in- along with their skills in teaching be-alter body contours, and it usually is cluding frequency of contact), coping havior change, are in key positions to:not considered as a surgical proce- style, and stressful life events amongdure for weight loss (117). Investiga- others (123,129-133). ● educate physicians and other healthtors in this country have studied the The best studied metabolic compen- care professionals about the impor-effects of high-volume liposuction on satory responses occurring with weight tance of weight-loss maintenance;insulin action and risk of coronary ar- loss is the concomitant decline in met- ● help the public, as well as othertery disease. They reported no im- abolic rate that results in what has health care professionals, to under-provement in metabolic abnormali- been termed an energy gap (134). This stand the difference between weightties (118). This contrasts with the energy gap, estimated to be about 8 loss and weight-loss maintenance;findings of other workers reporting kcal/lb lost/day, points to a post-weight and February 2009 ● Journal of the AMERICAN DIETETIC ASSOCIATION 341