2. the environment within which indi- mal BMI range. In addition, it is im- into their patients’ individualized care
viduals 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 a
as 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), involves
cietal tendency to protect against un- ● prevention of weight gain or stop- gathering the necessary information
derconsumption and volitional physi- ping weight gain in an individual to formulate a diagnosis and develop
cal activity, there are clear pathways who has been seeing a steady in- a care plan. Baseline weight and
for action. First, the one in three crease in his or her weight; health indexes should guide weight
adults (9) who can currently maintain ● varying degrees of improvements in management goals and are necessary
a 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 status
do 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 reflecting
individual and population levels is vi- and exercise behaviors; and short- and long-term changes in body
tally important. Next, it is crucial ● improvements in eating, exercise, fat, and must be correlated to health
that we find ways to optimize individ- and other behaviors. risk.
ualized treatments appropriately. Fi- The standard measurement for
nally, with the most rapidly growing Health can be improved with rela- weight status is BMI, calculated as
population category being those who tively minor weight losses. A weight kg/m2. Overweight is defined as a
are severely obese (10), it is necessary loss of 10% may ameliorate health BMI of 25 to 29, whereas higher
to understand and effectively treat risks associated with excessive body BMI values reflect more excessive
that portion of the population whose weight (12). Health care providers amounts of body fat (12). There are
health is most greatly compromised must help patients to accept a mod- differences even in the community of
by 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). The
has 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 overweight
evidence analysis work for the adult individuals who have two or more
weight management guidelines form risk factors associated with their
the basis of the information provided weight status. The Dietary Guidelines
in this position paper (11). The recom- The goals of weight for Americans 2005 (17) recommend
mendation 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 are
ing major recommendation from the available, but for most evaluations a
guidelines. 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 care
nation of the conclusion statement providers and/or referring physicians
grading, 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. A
The goals of weight management go tion. It is essential to include each of medical examination should rule out
well beyond numbers on a scale, these steps into weight management physiologic causes of increased body
whether or not weight change is one care plans. ADA’s Evidence Analysis weight and assess health risks and/or
of 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 reviewed
alistic 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 an
of 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. medical assessment, a psychological
evaluation may be indicated. Screen- A. Anthropometrics
ing for barriers to successful weight ● Height
loss such as depression, post-trau- ● Weight
matic stress disorder, anxiety, bipolar ● Body mass index
disorder, addictions, binge eating dis- ● Waist circumference
order, and bulimia is necessary. Stud- B. Medical
ies 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 future
priate 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-traumatic
health 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 and
mate 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 and
cumference 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, and
quality-of-life measures) are impor-
Figure. Factors to assess during weight management intake interviews.
tant to address to optimize a weight
management intervention. Factors
related to food access, food selection, part of an assessment. However, met- height in centimeters)–(5 age in
functional 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 in
portant 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 to
should 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 be
the 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, exercise
equately 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 can
tritional 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, there
records 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 multidisciplinary
baseline 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 a
ment 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 benefit
332 February 2009 Volume 109 Number 2
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 prevalent
sume a leadership role to design and to act as key drivers for initiating food in dietary surveys and appears to be
activate 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, little
team 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 with
role 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 of
continue 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 between
ing, dynamic process that involves these two sets of homeostatic signals
not only initial data collection, but reflects the brain’s recognition of the Diet Composition
also continual reassessment and current dynamic state of energy A low-fat, reduced-energy diet is the
analysis. Assessment provides the stores and the changing nutrient flow best studied weight-loss dietary
foundation 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 both
REGULATION 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 for
important 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 are
mendation 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 and
A 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 combination
reduction strategies may vary from a food intake (eg, perceived pleasantness, with lifestyle counseling and activity
focus 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, the
bination 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 the
In addition, strategies have included very powerful determinant of food in- carbohydrate content of their diet as a
changes to meal frequency, meal tim- take and inappropriate sensitization weight loss strategy. As glycogen
ing (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 dramatic
strategies, 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 body
tion 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 randomized
systems govern food intake: the ho- domized study with high dietary con- controlled trials lost more weight at 6
meostatic system and the hedonic trol helps to evaluate affects of energy months than individuals assigned to
system. Although both systems are reduction on weight loss per se, longi- the low-fat, reduced-energy diet, but
regulated 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-carbohydrate
to 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. basis of the dietary component of a since it is has not been shown to be pears to be an important weight gain
comprehensive 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 marketplace
carbohydrates is a practical way to EAL Recommendation “In order food and drink portions now exceed
create a caloric deficit of 500 to 1,000 to meet current nutritional recom- standard serving sizes by a factor of
kcal 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 describe
to 2 lb per week” (Rating: Strong, the diet component of a comprehen- this perception of large portions as
Imperative) (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 also
and/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 the
dicates that focusing on reducing car- ommended levels on weight manage- value of portion control comes from
bohydrate 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 experimental
ergy 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, and
greater weight and fat loss than tra- energy diet has emphasized the diffi- self-service vs preserved food items
ditional 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 intake
ences 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 trials
treme 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-selected
practitioners 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 replace
short-term use in patients with osteo- tors that influence individual adher- usual evening snacks (11), and a
porosis, 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 control
tein 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 energy
thought 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 entrée
stances, 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 Frequency
rated but are not essential for diets duced portions may be more or less Many RDs encourage weight loss
appropriate 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. that an erratic schedule leads to poor vs nonbreakfast consumers. Three a weight maintenance phase of their
food 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 at
weight gain. Generically prescribing sumers are associated with higher both 12 weeks ( 7% vs 4% of initial
a 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, with
weight 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 diet
sumption affects energy intake and fast-eating habits of the study par- plan (47% vs 64%; P 0.001) (11). To
thereby weight loss. Unfortunately ticipants interacted with treatment date, structured meal replacement
the 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 a
is not extensive with no randomized measured weight change (11). Fur- weight gain prevention strategy have
controlled 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 strategy
ings 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 conventional
the reason for this lack of clarity and tions for optimizing body weight con- food choices. These specific concerns
fair 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 advising
but as yet it is not clear where the ents. Helping a client to find a meal clients utilizing meal replacements
under-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 careful
ticipants) comes from (ie, mispercep- ronment of high-energy food choices selection of the conventional foods
tion 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, meal
other eating episode by 15 minutes sumption of greater energy intake bars, or calorie-controlled packaged
whereas another study used main during the day may be preferable to meals) may be used as part of the diet
meal, beverage meal, light meal, or evening consumption” (Rating: Fair, component of a comprehensive weight
snack categories) (11). Finally, the Imperative) (11). management program. Substituting
characteristics of people who routinely one or two daily meals or snacks with
have a regular vs irregular meal pat- meal replacements is a successful
tern are still unknown, making it diffi- Meal Replacements weight loss and weight maintenance
cult 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 easily
routine exercise habits). overwhelm anyone trying to lose Very-Low-Energy Diets
Breakfast consumption possibly weight. Meal replacements, contain- Unlike meal replacements, which are
plays a role in weight management ing a known energy and macronutri- designed to replace only one or two
through an influence on appetite con- ent content, are a useful strategy to meals per day, a very-low-energy diet
trol, 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 (or
weight regulation is primarily fo- ing isocaloric diets have shown equiv- 6 to 10 kcal/kg) or less per day, is
cused 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 the
reliance on self-report, definition of plans compared to reduced-energy Daily Value of essential vitamins and
what constitutes a breakfast, and diet treatments (11). Three of these minerals. The purpose of using a
lack 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. 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 loss
possible. 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 of
phase 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 between
for 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 indicate
results in significant weight loss of 15 significant initial weight loss, studies that physical activity in the range of
to 5% of initial body weight over 12 to report varying levels of weight regain 11 to 12 kcal/kg/day maybe necessary
16 weeks, maintenance of that weight based on differences in weight main- to prevent weight regain following a
loss 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 also
mended against the use of very-low- indicate that a high level of daily
energy diets. The decision was based physical activity may be necessary to
on 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 a
low-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 maintained
regain 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 lose
maintenance 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 their
have 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, an
A recent meta-analysis was con- in body weight with physical activity energy equivalent of walking 4 miles
ducted 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 restricting
weight 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 the
vs 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 to
long-term weight loss (6.3% 3.2% vs fluctuations or compensatory changes weight management goals. The first
5.0% 4.0%; P 0.2) (43). Overall at- in energy intake. Depending on body recommendation, to reduce the risk of
trition in the six studies was not dif- size, fitness level, and exercise inten- chronic disease in adulthood, is for 30
ferent 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 help
has been increasingly prescribed be- comparison, an extra 1,000 kcal could manage body weight and prevent
fore bariatric surgery to reduce over- easily be consumed by miscalculating weight gain in adulthood, is to engage
all 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 of
the use of very-low-energy diets for at spite its modest impact on weight the week. Finally, to prevent weight
least 2 weeks reduces liver size al- loss, physical activity is important for regain after weight loss, engage in 60
though 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. The
Further 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 in
surgery 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 health
very-low-calorie diet, defined as 800 regardless of BMI (47). Therefore, it is benefits of physical activity and have
kcal or 6 to 10 kcal/kg or less, results important that physical activity is in- similar recommendations to the 2005
336 February 2009 Volume 109 Number 2
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 Weight
Physical Activity Guidelines make pants was 30 3.4, the efficacy of pe- Loss. A limited number of studies
recommendations in weekly vs daily dometer use in people with severe have evaluated the intermediate (6 to
doses: at least the equivalent of 150 obesity (BMI 40) was not evaluated. 12 months) effectiveness of cognitive
minutes/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 neutral
tial health benefits and 300 minutes/ quality, 6-month randomized con-
week of moderate-intensity physical Behavioral Interventions trolled trial (86 obese adults) provides
activity for more extensive health ben- evidence that intermediate duration
efits (45). Acknowledging the great in- Historically, cognitive behavioral treat-
ment of obesity developed from the be- (6-12 months) behavioral therapy and
terindividual variability that exists behavioral therapy combined with a
with 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 weight
150 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 obesity
recommendations that will help clients
apy can help individuals develop a set receiving the weight-loss educational
achieve 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 exercise
weight gain, weight loss, and sustain- What Is Cognitive Behavioral Therapy? Cog-
habits, and guidelines for increasing
ing 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 is
physical activity. These small, rela- often prompted by antecedent events havior therapy (ie, 25 weekly sessions
tively 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, behavior
daily 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 to
promote 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 evaluating
step goal consistent with the 30 min- istics (61): it is goal-directed (measur- the effects of cognitive behavioral
utes of moderate-intensity physical able outcomes), process-oriented (helps therapy on weight loss over 2 years
activity recommendation of the 2005 people decide how to change), and ad- have also shown positive effects on
Dietary Guidelines (53); however, a vocates small rather than large weight control though weight gain is
higher 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 neutral
ical activity alone or to maintain a riety of problem-solving tools and quasi-experimental (84 participants
weight loss. A recent meta-analysis of usually includes multiple components received behavior therapy) and two
26 studies (eight randomized con- such as nutrition education, keeping positive randomized controlled trials
trolled trials and 18 observational food and activity records (ie, self-mon- (65 participants received behavior
studies) 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 of
baseline (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 the
an 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 lost
Noted 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. some weight regain but participants ings were observed in the Look the results of lifestyle intervention
remained at a lower weight than AHEAD study, which compared the studies can be replicated in the real
baseline. Studies that included a effectiveness of a behavioral interven- world, researchers designed the Good
very-low-calorie diet to initiate rapid tion program and enhanced usual Ageing in Lahti Region Program, a
initial 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 outcomes
This is not a statement recommend- viduals with type 2 diabetes (32). Not were less robust than more intensive
ing very-low-energy diets or suggest- only did individuals in the behavioral efficacy studies, favorable lifestyle
ing that very-low-energy diets are intervention group lose more weight changes were reported and weight
more beneficial than low-energy di- at 1 year, they also observed greater gain was prevented, suggesting on
ets.]” (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-based
and cardiovascular disease risk. levels. behavioral treatment on weight gain
Given the beneficial effect of weight The Finnish Diabetes Prevention prevention, weight loss, and weight
reduction 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 diet
weekly 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% to
for 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 32
for the later phases of the study (12 to risk reduction remained after discon- weeks) but slowly regain weight over
24 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 weight
tion 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 to
on 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 a
Participants 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 weight
control group (single advice-giving ber diet; and engaging in physical ac-
loss at follow-up (ie, approximately
session) or one of two behavior modi- tivity. These findings are encouraging
10% and 8% of their initial body
fication 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 of
observed 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 set
ferences in weight loss between the return to baseline weight in the great of skills to handle barriers to eating
intervention 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 endeavor
influence 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 and
showed that intensive behavior mod- tervention groups; therefore, these promotes energy-saving devices (8). A
ification is not only more efficacious in studies do not simulate treatment in healthful lifestyle requires significant
producing 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 monitoring
pharmacotherapy (33). Participants behavioral treatment in combination energy intake and activity, all of
in 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 more
type 2 diabetes than those taking conditions. practical by providing structure and
metformin or placebo. Similar find- As a means to determine whether reducing time spent in meal planning
338 February 2009 Volume 109 Number 2
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 to
be 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 energy
prehensive 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 receptor
the multiple strategies for cognitive rhythmias. Sibutramine is also con- agonists; and inhibitors of fatty acid
behavioral therapy (ie, self-monitor- traindicated with monoamine oxidase synthesis (82).
ing, stress management, stimulus inhibitors and other serotonin uptake Leptin has undergone phase two
control, problem solving, contingency inhibitors, which include medications testing, but data at this time do not
management, cognitive restructur- for depression and migraine (76). The indicate leptin has the potential to be
ing, and social support). Cognitive be- evaluation of the reported cardiovas- clinically useful for the modification of
havior 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 stage
weight loss. Continued behavioral in- (77). three trials. Fenfluramine, alone or in
terventions 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 slowed
tify 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 side
techniques (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 the
and 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 loss
tant to match behavioral tools with
Phentermine. Phentermine is a sympa- do not have standardized amounts of
each individual’s unique set of char-
acteristics. These are the type of thomimetic anorexogenic agent and active ingredients and harmful effects
questions that need further attention the most widely prescribed weight have been reported (88,89). Certain
and 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 efficacy
Pharmacotherapy placebo-controlled studies available, for short- or long-term weight loss
Current 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 weight
obesity (BMI 30 or BMI 27 to 29 cebo. Side effects include insomnia, loss, but are not FDA-approved, and
with one or more obesity-related dis- constipation, and dry mouth. Inter- over-the-counter and herbal weight
orders) include sibutramine and orl- mittent dosage in a randomized con- loss preparations are currently not
istat. 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 affect
mine, 29 for orlistat). Medication lence of obesity speaks to the unmet obesity-related comorbidities (92). If
combined with lifestyle modification medical needs for safe and effective such reductions are achieved with
is more effective than placebo with medications (81). Pharmacotherapy re- medications, data indicate that those
lifestyle modification in promoting search is currently focusing on: central medications be continued long-term
weight 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, it
therapies have not been evaluated in (topiramate, zonisamide), and some should be noted that medications can
children or older adults and there is dopamine antagonists; leptin/insulin/ lead to modest weight losses at 1 to 2
limited 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 safety
Sibutramine. 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 of
dicates 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. cluding behavior therapy, diet, and may be reduced by the placement of were reduced (105). In the United
physical 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 the
proved 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 population
collaborate with other members of Roux-en-Y gastric bypass, and the ex- (106). Vogel and colleagues reported a
the health care team regarding the tensive gastric bypass (biliopancre- reduction in predicted coronary heart
use 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 sustained
that pharmacotherapy may enhance and also bypass the duodenum and weight loss as a powerful intervention
weight loss in some overweight and other segments of the small intes- to reduce future rates of myocardial
obese adults” (Rating: Strong, Im- tines, thus producing malabsorption infarction and death in the morbidly
perative) (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 a
Surgery skilled surgeons (97-99). A fifth pro- bariatric procedure and the initial
Surgery, with its inherent structural cedure, vertical banded gastroplasty, costs of surgery were amortized over
change, 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 open
tenance. 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 bowel
related 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 open
rion 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 by
rently 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. For
sion, and sleep apnea are present, a cases per year had lower mortality,
purposes of comparison, a range of
BMI between 35 and 40 may be con- shorter length of stay, lower overall
weight loss defined as percentage of
sidered 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 used
tients with BMIs of 30 to 34.9 who
have comorbid conditions that could reported 21.9% complications during (97). The effectiveness of the surgical
be cured or markedly improved by the initial hospitalization, which in- procedures for weight loss range from
substantial weight loss is under re- creased to 39.6% during the first 180 47.5% excessive weight loss for the
view 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 the
weight 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 weight
improved 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 and
knowledgeable 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 reduce
nisms of producing weight loss, as new health-related conditions in per- surgical risk before a second stage of
well as the complications and con- sons with morbid obesity (104). Swed- a gastric bypass or the duodenal
cerns. It is of note that surgical pro- ish investigators have recently pub- switch procedure. The excess weight
cedures to promote weight loss are lished their 10.9-year follow-up of loss reported for the sleeve at 1 year
continually evolving. At the current operated vs nonoperated controls, approximates 46% (110-113). It is of
time there are four commonly used which clearly shows long-term weight note that surgery appears to rule over
procedures 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 responses
bination 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. 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 make
during screening to evaluate weight chor either end of this continuum. treating individuals with overweight
history, 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 set
iors (ie, binge eating) to assist in tion professionals must understand
of strategies and/or skill set. each of these aspects as they develop
electing 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 nutrition
formed of the lifestyle changes neces- conclusive with retrospective studies
sary to decrease postoperative com- professionals should also be aware of
of successful weight-loss maintainers
plications 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). Issues
when 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 consensus
modify eating, smoking, and exercise dicated that individuals with obesity
on amount of weight loss, weight loss
behavior. After surgery an RD may lacked willpower (135). These charac-
duration, time between weight loss
play 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 professionals
plementation requirements. Such loss maintenance may be an outcome should understand the importance of
adjunctive 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 to
be a standard component of surgical a successful outcome. Such variables effectively help their clients maintain
weight management (115,116). All pro- might include factors impacting met- normal weight and sustain long-term
cedures 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 expenditure
Its 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 among
dure for weight loss (117). Investiga- others (123,129-133). ● educate physicians and other health
tors 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 other
tery 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 weight
ties (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
