Energy balance and its components: implications for body weight regulation

A fundamental principle of nutrition and metamorphosis is that body weight change is associated with an asymmetry between the energy contentedness of food eaten and energy expended by the body to maintain life and to perform physical work. Such an energy balance model is a potentially potent creature for investigating the regulation of body weight. however, we need a better understanding of the components of energy remainder and their interactions over versatile time scales to explain the natural history of conditions such as fleshiness and to estimate the magnitude and likely success of curative interventions. therefore, the ASN and the International Life Sciences Institute convened a panel composed of members with expertness in burden management, energy metabolism, physical activity, and demeanor to review the publish scientific literature and to hear presentations from other experts in these fields. The Consensus Panel met 9–12 May 2011 in Chicago, IL, and was charged to provide answers to the following 5 questions :

  1. Explain energy poise and asymmetry in terms of a biological system in which energy consumption and energy outgo change over time in response to the environment .
  2. What are the interactions between the components of energy remainder and how are they regulated ?
  3. What is the veracity of some of the popular beliefs related to department of energy libra ?
  4. What limitations do we face in the study of energy balance and its components ?
  5. What research would better inform our cognition of energy poise and its components ?

Question 1: Explain energy balance and imbalance in terms of a biological system in which energy intake and energy expenditure change over time in response to the environment

Human physiology complies with the inaugural law of thermodynamics, which states that energy can be transformed from one form to another but can not be created or destroyed. This jurisprudence is normally formulated as follows : the rate of change in body ES10 is peer to the remainder between the rates of EI and EO. All of these terms are expressed as energy per unit of time. EI chiefly consists of the chemical energy from the food and fluids we consume. EO includes the beaming, conductive, and convective heat lost ; any work performed ; and the latent heat of vaporization. ES is the rate of change in the consistency ’ south macronutrient stores. The energy poise equality ( ES = EI – EO ) is a statement of the rationale of energy conservation.

Components of intake

Energy intake includes 3 major macronutrient groups—carbohydrate, protein, and fat—and a smaller component from alcohol. once ingested, the web absorption of the major macronutrient groups is variable and incomplete, with faecal losses accounting for ~ 2–10 % of crude EI. The internet absorption of dietary energy components varies among individuals and is pendent on the specific foods eat, how they are train, and intestinal factors. The metabolizable energy ( afterlife referred to as EI ) of a diet represents the difference between the absolute energy of consume substrates and the department of energy losses found in feces and urine. normally used department of energy densities for carbohydrate ( 4 kcal/g, 17 kJ/g ), protein ( 4 kcal/g, 17 kJ/g ), and adipose tissue ( 9 kcal/g, 38 kJ/g ) present population averages for metabolizable energy, which is the measure of fuel actually available to cells for conducting biological processes. Digestibility depends on the composition of the food token and on its contentedness of character and other indigestible components. such components can mechanically limit the access of digestive enzymes to food that would potentially be digestible. For example, nuts and other plant materials have cell walls that can not be digested by gut enzymes, and they thereby protect the cell contents from digestion if not masticated sufficiently to disrupt the cell structure. These effects can have a big impact on the absorption of absorb macronutrients. The unevenness in absorbent efficiency depends on many extra factors ( eg, gut flora, food preparation, diet constitution ), which may explain the individual differences in metabolizable EI.

Components of expenditure (EO)

Absorbed carbohydrates, proteins, and fats are transformed in vivo to substrates that can ultimately either be oxidized to produce metabolically utilitarian energy that drives biological processes or they may be stored. The rate of whole-body energy outgo, or EO, varies within a 24-h period and across the life span. Expended energy reflects fuels metabolized for increase, body maintenance needs, physical activeness, pregnancy and suckling, and many other processes. The main energy expending terms are REE, TEF, and AEE. REE is the rate of energy consumption at rest and comprises approximately two-thirds of EO. REE varies between and within individuals depending on body size, consistency composition, and late energy asymmetry. Greater total weave bulk increases REE, and the contribution of tilt weave is greater than fat weave. furthermore, within lean tissue, high metabolic organs such as the genius, heart, kidney, and liver contribute disproportionately to REE. There is besides a large variability in REE ( ~ 250 kcal/d, ~ 1000 kJ/d ) that is not explained by differences in soundbox typography ( 1 ). The TEF is the obligatory energy consumption that is associated with digestion and process of absorb foods. Diet typography has a firm effect on TEF. There is a hierarchy of macronutrient effects on the magnitude of TEF, with isocaloric amounts of protein > carbohydrate > fat. normally, TEF is assumed to be a specify percentage of EI, but variation between and within individuals occurs. AEE is the department of energy consumption pace during bodily process and can be farther partitioned into exercise energy consumption and nonexercise action thermogenesis.

Components of storage

Triglycerides, which are award within adipose weave, are the body ’ s major fuel substitute. A lean adult has ~ 35 billion adipocytes, each containing ~ 0.4–0.6 μ guanine triglyceride and totaling 130,000 kcal stored energy. An extremely corpulent adult can have 4 times as many adipocytes ( 140 billion ), each containing twice angstrom much lipid ( 0.8–1.2 μ thousand triglyceride ) and totaling ~ 1 million kcal stored energy ( 2 ). ES reflects net changes in the body mass of carbohydrate, protein, and fat. Carbohydrate is stored chiefly in the form of intracellular glycogen in bony muscle and liver-colored. The total batch of glycogen is relatively little, several hundred grams, and employee turnover is rapid ; maximal amounts are observed in the postmeal state. Water is weakly bonded to glycogen so that glycogen ’ sulfur deduction and catabolism besides involve alterations in fluid remainder. Body protein takes many specific forms and, as with glycogen, is associated with urine but at a lower value per gram. Lipid in the form of triglyceride is the largest informant of store department of energy in most adults and has no water associated with it. Any asymmetry between the consumption and use of these macronutrients will lead to an revision in body composition. The energy stored per unit body system of weights of carbohydrate, fat, and protein varies well, specially when accounting for the consort intracellular water. Furthermore, dietary carbohydrate intake has an impingement on nephritic sodium body waste, which results in changes in extracellular fluid. Therefore, changes in body weight are expected when the macronutrient composition of the diet is altered, even when the department of energy content of the diet is held changeless. The long-run constancy of body burden is often considered a marker of zero ES, and therefore department of energy balance. however, as described above, changes in body weight besides include changes in body water, which may be variable star, and consequently weight change may not directly represent energy imbalances, particularly over the short-circuit term.

Question 2: What are the interactions between the components of energy balance and how are they regulated?

The 3 chief terms of the energy remainder equation continuously switch over prison term. Beginning at invention, ES remains positive, on average, throughout growth and development. This positivist energy imbalance is reflected by increasing body weight. If adult weight is then maintained over the long term, average ES approaches zero, and an approximate median state of energy remainder is present. however, most adults gain fatten throughout their lives and in later animation lose bony muscleman ; the energy content of body fat change is much higher than that of lean tissue change. Thus, evening with weight stability, “ perfect ” energy balance over the long condition does not occur in most older adults. Over a 24-h period, a typical person eats several meals during the day, and department of energy symmetry is powerfully positivist during and soon after each meal. Energy end product is continuous but with increases due to episodic physical activity and decrease during sleep. Energy balance is therefore highly variable over a 1-d period, and this variability is shown in dynamic changes in ES. Most adults besides vary their casual eat and activity patterns ; thus, ES besides varies from day to day, with department of energy libra achieved only when averaged over longer prison term periods. The growth of fleshiness by necessity requires positivist energy imbalance over and above that required for normal increase and development. As in list individuals, a state of energy balance over the long terminus with similar short-run fluctuations in consumption and consumption is besides approximated in corpulent individuals, but in corpulent individuals this is achieved with a higher sum of body fat. The counterpart of excess weight derive is a negative energy balance leading to weight passing over time. For case, if an acute reduction in EI is maintained over clock time, then, assuming patterns of behavior remain unaltered, changes in the 3 processes—reduced REE, AEE, and TEF—will gradually besides lower EO as weight is lost. finally, these passive voice compensatory effects will lead to a diminishing energy imbalance with ultimate restoration of a firm express at a lower body burden. Although it is unclutter that EI and EO are partially of a biologically regulate system, the claim nature of how this system works in humans has not been fully established. Two different system designs have been generally discussed, a “ set point ” and a “ settle point. ” The idea of a fix point is borrowed from the field of engineering in which feedback control systems are designed to regulate a detail varying to match a specify aim. In contrast, a settling steer has traditionally been used to describe a arrangement without active feedback control of food consumption and energy consumption. Models that do not immediately specify a set-point rate but that include active feedback control have besides been called settling-point models. These 2 systems do, in fact, overlap, and there are insufficient data to decide whether one or both are valid. What is unclutter, however, is that perturbations in the components of energy intake or expending consequence in compensatory changes in these components. These include passive voice compensatory changes such as an addition in energy outgo with an increase in torso size and active compensation such as changes in food inhalation after exercise. The stick to is a brief review of the interactions among the energy balance components.

Food intake on subsequent food intake

Food consumption is temporally variable. We eat meals that reflect the satiation that develops during a meal and repletion between meals. The department of energy message of a given meal is highly variable between individuals and highly variable between meals in an individual. however, the variation in full thermal consumption summed across all meals over a day is army for the liberation of rwanda less variable. This suggests that there is meal-to-meal recompense of intake, which is confirmed by a negative correlation coefficient between consecutive meal energy contented. If we over- or underconsume energy in one meal, we partially compensate for that consumption in subsequent meals during the same day. In addition to variation in inhalation between meals on a given day, we besides vary the come of food eaten each day. Energy expending rarely shows the lapp academic degree of version across days. Hence, we are about perpetually in energy imbalance on the clock time scale of hours or days. When a given day ’ south inhalation and consumption are plotted against each other, there is little association. It is lone when they are averaged over much longer periods ( weeks ) that there begins to be a libra strike between inhalation and outgo ( 3 ). The panel emphasized that this is a key compass point that is sometimes overlook : energy balance as a concept depends on the time domain over which it is considered. We are always in energy asymmetry, but the relative asymmetry is greater over the short terminus than over the long terminus. Food composing has been suggested to have a boastfully affect on repletion and repletion. It is broadly believed that the major macronutrients differ in their effects, with protein having a greater effect than carbohydrate, which has a greater effect than fat. however, the data are not reproducible among all studies. In addition, many environmental factors such as sociable context, angstrom well as liking and wanting food, play an important function in the energy consumed at a meal. repletion and repletion depend on several physiologic and molecular mechanisms. Satiation mechanisms include distention of the gastrointestinal tract communicated to the brain and the secretion of a count of gut peptides that interact with receptors chiefly in the hind-brain. A factor potentially linked to repletion is the hormone ghrelin, which is produced by the stomach. Ghrelin is singular among know gut peptides in that it is orexegenic. Its production increases with time since the final meal, and injections of ghrelin promote food inhalation. The hormonal regulation of food intake has been discussed in greater detail elsewhere ( 4 ). In addition, there are a big numeral of centripetal and cognitive stimuli that affect food intake and physiology. For example, liking and wanting food can overcome feelings of repletion and repletion and lead to food intake despite feeling entire or not being hungry. besides, sensory-specific repletion can affect food intake—although people may feel broad after a large main course of savory food, they are still able to eat a fresh dessert.

Food intake on energy expenditure

After the overconsumption of energy there is an increase in soundbox size leading to a passive increase in EO. This is due to the follow factors : an increase in REE, chiefly as a result of an increase in tilt weave mass and to a lesser extent an increase in fat mass ; an increase in AEE associated with the increased price of moving a larger soundbox mass ; and an increased TEF due to greater EI. ultimately, there is an extra department of energy price for tissue deposit and increased protein employee turnover. There has been a long-standing debate about whether, in addition to these passive effects on EO, there is an active stimulation of expending during overfeeding that opposes weight gain ; however, there is little attest for an active effect on REE during overfeeding when one accounts for the extra energy monetary value of tissue deposition. It has besides been suggested that nonexercise activity thermogenesis may increase to partially offset the impression of overfeeding ( 5 ). This effect was reported to be ≤ 500 kcal/d ( 2100 kJ/d ), which would be a major compensatory agent for opposing weight addition when caloric consumption is increased, but early studies have failed to find effects of a alike magnitude ( 6, 7 ). During limitation of food intake there is a reduction in whole-body EO, due in part to the reduction in body mass that follows the lower calorie intake. This can be accounted for by reductions in REE secondary coil to loss of thin and fat mass, reductions in AEE due to deoxidize amounts and costs of natural process, a decrease in TEF due to lower EI, largely caused by reductions in protein employee turnover and its associated energy cost. In addition to the passive compensation described above, there is evidence for an active reduction in REE during calorie limitation whose magnitude is dependant on the degree of calorie restriction ( 8 ). many studies have addressed the effect of meal patterning on REE during burden constancy. On median, about tripling the numeral of daily meals but providing the lapp entire amount of energy had a scantily detectable effect on REE, which suggests that meal pattern does not elicit a greater or lower recompense in expending.

The effect of exercise on EI

If demands for energy are met from food consumption then it is much assumed that there must be some mechanism that provides a link between outgo and intake. however, studies of short duration in which EO is increased by exercise showed no compensatory switch in EI over 1 or 2 d. As the duration of the studies increased, evidence for recompense emerged with longer-duration studies showing greater but incomplete recompense. Data from several studies showed no relative between AEE and subsequent slant change. therefore, low AEE as measured by doubly label water at a one prison term indicate was not a forecaster of weight gain over a prolong period ( 9 – 11 ). cross-sectional data on AEE that span the late increase in the prevalence of fleshiness showed that during this long period of meter, levels of AEE have not declined ( 12 ). however, late model knead has suggested that declines in occupational bodily process over the past 5 decades could explain the respect increases in body weight over the lapp menstruation ( 13 ) but alone if such action changes were not compensated for by nonoccupational natural process changes in or modulations of food intake. exercise interventions result in big individual variation in body weight reception. depart of the version may be due to adherence. however, even when practice sessions are close supervised, and hence the adhesiveness issue is eliminated, there is placid a enormous variation in response, with some individuals losing significant amounts of weight and some actually gain weight ( 14 ). Measurements of food inhalation before and after exercise suggest region of the unevenness in weight unit change due to exercise lies in how wholly individuals compensate for their practice prescription with elevated food consumption, which corresponds to their hunger after exercise.

The effect of exercise on EO

A democratic mind is that a major profit of forcible activity comes not entirely from the actual energy that is expended during the practice itself but besides from an after-effect of physical action on REE. There are data showing a positive effect of vigorous or moderate physical activeness on REE. This follows 2 separate phases : a big effect that lasts ~ 2 henry and a smaller but more prolong effect that could take up to 48 h to return to baseline ( 15 ). This is called excess postexercise oxygen consumption and accounts for ~ 6–15 % of the energy expended during an exert seance ( 16 ), which adds little to TEE. Another popular impression is that exercise train results in body-composition changes that generate an extra energy benefit of exercise mediated through REE. But such potential effects of exercise discipline on REE may have been confounded because the post–exercise aim REE was measured excessively soon after the concluding exercise bout, contaminating it due to excess postexercise oxygen consumption ( 15 ). Measurements that are not sol baffled hint that the impact of use aim on REE is negligible. Whether accustomed exert produces long-run changes in other components of EO is indecipherable. exert interventions may be counteracted by compensatory reductions in physical activity at early times of the day, although the data on this point are mixed. Some studies found that practice had no overall effect on daily EO because the individuals reduced their normal activities. other studies reported that there was no bodily process recompense from the summation of an drill interposition and thus an increase in EO was observed. indeed, in some studies there was an increase in EO beyond that accounted for by the exercise alone. These data emphasize a major period that we would like to reinforce. All of the components of energy balance interact with each other. consequently, it is absolutely necessary to take all of these interactions into circumstance when conducting intervention research in the field of fleshiness. To take a simpleton model, it may not be very utilitarian to enhance physical natural process but to allow subjects to eat what they wish ( and frankincense compensate for their lift consumption ).

Question 3: What is the veracity of some of the popular beliefs related to energy balance?

A. “The typically observed weight-loss plateau at 6 to 8 mo after a weight-loss intervention is primarily due to a reduction in energy expenditure, ie, slowed metabolism.”

Although the measurement of EO at the tableland is decreased, it does not decrease to the measure of the positive or self-reported energy intake. therefore, the tableland may well be attributed to failure to comply with the diet ( 17 ). Modeling studies support this rendition and suggest that if subjects had complied with the prescribed diet, the tableland due to metabolic change would not have occurred for several years, which would have led to much greater weight loss than that observed ( 18 ). These data besides emphasize that, whereas it is potential to cognitively intervene in our food consumption amounts, such interventions are highly difficult to sustain because of the biological and psychological drives to eat.

B. “Obesity is due to low energy expenditure, ie, low metabolism.”

The being of a broken metabolic pace in fleshiness was mistakenly reported in early studies in which the REE was inappropriately normalized by dividing it by body slant. A simple division of REE by total weight leads to a lower calculate of the mass-specific metabolic rate because corpulent people have an increased relative amount of body fatten, which has a lower metabolic rate than does lean tissue. This standardization erroneousness led to the impression that low metabolism was the cause of the fleshiness. The error was compounded by a misapply of the energy libra concept, which is by rights applied merely at the level of the entire organism. thus, it is disable to consider metamorphosis per kilogram of body system of weights, or tied per kilogram of nonfat mass, as a component of this system. A poise is not struck between total food intake per individual and outgo per kilogram but rather between energy intake per individual and energy consumption per individual. Lower REE per kilogram of body weight consequently can not be a “ campaign ” of fleshiness. In absolute terms, corpulent people expend more energy than do their lean counterparts. however, this observation should not be overinterpreted to infer that low REE is not a risk gene for fleshiness. This is because corpulent people might have had a lower REE than that predicted for their torso size and composing before gaining their surfeit weight. consequently, it is unclear the extent to which fleshiness results from repress energy outgo, but it is clear that the care of fleshiness is not due to reduced energy consumption.

C. “It takes a reduction of 3500 kcal (15,000 kJ) of energy intake to lose 1 lb of body weight.”

The beginning of the “ 3500 kcal per egyptian pound ” convention is based on the calculate energy content of body weight change and is often misapplied to predict the weight-change time run after a given intervention ( 19 ). This is a fundamental mistake because no time period is specified for that intervention. The mental picture is given that even a temp intervention will therefore solution in a permanent wave body slant change. furthermore, the erroneous application of the rule to predict the impact of a permanent wave intervention gives the impression that a linear change in consistency weight is expected over drawn-out periods of meter, which is known to be false. Rather, even when perfective adhesiveness to an intervention with no active compensation is assumed, it is generally acknowledged that system of weights change will slow over clock time due to passive voice compensatory changes in energy expending that occur with the system of weights change. therefore, the gore recommended that the 3500 kcal per egyptian pound rule should no farseeing be used. With the habit of a model that accounts for the passive compensatory effects on EO, a fresh rule of thumb representing a best-case scenario has been proposed for the average fleshy person : every permanent 10-kcal change in energy intake/d will lead to an eventual weight change of 1 pound when the torso weight reaches a newfangled steady state ( ~ 100 kJ/d per kilogram of weight unit change ). It will take about 1 y to achieve 50 % and ~ 3 yttrium to achieve 95 % of this weight loss ( 20 ). Whereas the above rule of thumb may be utilitarian for approximate estimations and represents a significant theoretical improvement over the 3500 kcal per pound rule, a more accurate appraisal of the total and time course of predict weight change for a given decrease in EI may be very valuable and instructive for an individual patient. newly developed dynamic energy libra models for burden loss necessitate complex calculations that are simplified for users in web-based programs ( hypertext transfer protocol : //bwsimulator.niddk.nih.gov ; hypertext transfer protocol : //www.pbrc.edu/the-research/tools/weight-loss-predictor ). Model predictions such as these provide a more realistic steer as to what patients can expect with changes in energy balance.

D. “Small changes in lifestyle can prevent or reverse obesity.”

small life style changes in either consumption or consumption ( activeness ) are being increasingly promoted as viable interventions. It is important not to have unreasonable expectations about the impact of such interventions on body slant. Because the 3500 kcal per thump rule has often been used to model the effects of such interventions, unrealistic predictions are frequently made about the probable weight-loss benefits of exercise and dietary interventions that make merely child adjustments to lifestyle. As note above, it is inappropriate to use the 3500 kcal per pound rule to model the effects of interventions. To illustrate this trouble, a 40-kcal/d ( 170-kJ/d ) permanent reduction in energy intake resulting from taxing sweetened beverages has been predicted to result in ~ 20 pound ( 9 kilogram ) of weight passing in 5 y according to the 3500 kcal per pound rule, whereas merely 4 pound ( 2 kilogram ) of system of weights loss is predicted using the raw rule of hitchhike ( 20 ). The recommendation that an fleshy or corpulent person should expend an extra daily 100 kcal ( 420 kJ ) in walk ( internet explorer, walking one mile a day ), given the raw rule of flick discussed above, would result in a weight unit personnel casualty of ~ 10 pound ( 4.5 kilogram ) over 5 y, as opposed to a loss of 50 pound ( 23 kilogram ) if the 3500 kcal per syrian pound rule is used. Although a 10-lb system of weights loss can much produce major health gains, which points to a potentially significant profit of little life style changes, it is not closely the come of weight loss from this physical action regimen that the 3500 kcal per impound principle suggests. furthermore, even the revised rule is an affirmative judgment of weight switch because it does not account for the potential active compensation of EI.

Question 4: What limitations do we face in the study of energy balance and its components?

Our ability to measure precisely person components of energy consumption or energy consumption is relatively poor in light of the potential impact of small changes described above on body weight, particularly over extend meter scales in free-living individuals. For model, the doubly tag water method acting has a preciseness of ~ 5 %, which translates to an doubt of energy consumption of > 100 kcal/d ( 420 kJ/d ). In accession, the accuracy and preciseness of energy consumption measurements by self-report in free-living individuals are much worse. thus, the unite error of assessing energy asymmetry can easily reach 1000 kcal/d ( 4200 kJ/d ) ( 21 ). This electric potential mistake prevents evaluation of the benefits of interventions that have a small benefit on burden change over time. New technologies presently in exploitation may be more accurate and precise, but that remains to be seen. Another limitation that we face is that body weight over a sidereal day, and between days, fluctuates unrelated to changes in energy stores because of changes in hydration and alimentary nerve pathway content, which are the primary contributors to the distinctive 1–2-lb daily fluctuations in weight. Yet another limitation we face is that the calculation of the energy deficit generated by a given diet requires knowing the energy necessity to maintain the baseline body system of weights. As stated above, the impreciseness is > 100 kcal/d when the most accurate methods presently available are used. The doubt of service line energy requirements translates to a considerable interindividual variability of weight unit loss, even if attachment to the prescribed diet is arrant. For exemplar, if the service line energy necessity of an corpulence or corpulent person is 100–200 kcal/d higher or lower than measured, then perfect adhesiveness to a diet will result in an error of ~ 5–10 pound ( 2.3–4.5 kilogram ) in bode weight transfer over a year because of measurement error entirely. This limit is less of a concern in studies designed to measure modal differences between groups. In inpatient studies, more precise measurement techniques are available, which thereby decreases measurement error. For example, whole-room calorimeters can measure EO with 1–2 % preciseness ( 22 ) and weighed, supervised food inhalation with mensural excreta can provide very accurate and precise measurements of EI. however, such studies do not represent free-living conditions. last, the characteristically long time plate ( ~ 1 y half-time ) for homo body weight and writing changes to occur make it difficult to study comprehensively the dynamics of department of energy balance wheel because we can not generally keep humans in metabolic wards for such prolong periods. even in a free-living site we can not track EI or EO for drawn-out periods using current technologies. We are thus limited to “ snapshot ” of periods of ~ 2 wk.

Question 5: What research would better inform our knowledge of energy balance and its components?

It is important to recognize that the energy poise system is interactional and complex : a change in one component can affect one or more other components. The panel identified the succeed significant gaps in our cognition that deserve future probe :

  1. Although we know much from short-run studies about the major components of energy balance, our cognition is hush deficient regarding their interaction over the long condition. consequently, we need long-run, longitudinal studies to learn the details of the relations between components of energy balance and changes in body composition and weight among children and adults .
  2. It has been shown that biological and psychological factors affect the components of energy balance. But generally, these have been studied independently of one another and an integrative approach is required. We need to know the relative importance of preingestive factors ( cognitive and sensational effects of food/meals ) on energy consumption, energy balance, and the physiologic response to a meal .
  3. Although our cognition of the broader implications of physical activity and exercise have been investigated, we need to understand the effects of different doses ( volume, intensity, model, timing ) and types ( endurance, immunity ) of exercise on 1 ) entire day by day department of energy consumption and its components ( REE, TEF, AEE ), 2 ) EI and food preferences, and 3 ) body typography and body burden in children and adults .
  4. The individual mutant in weight-loss reaction to energy counterweight interventions is striking, and therefore we need to know the mechanism or mechanisms creditworthy for the underlying active compensatory differences in department of energy intake, food preferences, and body weight in children and adults. In particular, we have about no information from energy balance studies subsequent to weight loss during the unmanageable time period of weight sustenance. How can we identify population subgroups or even individuals who will respond or not respond to a dietary or exercise treatment ?
  5. Measurements of energy remark and output are neither accurate nor accurate adequate to allow the calculation of energy balance over the appropriate timeframe needed to understand the mechanism creditworthy for excess weight addition. consequently, we need to develop new methods that can reliably quantify energy poise over cover time periods in free-living people .

The 1-d Consensus Conference included presentations from the following speakers : David Allison ( University of Alabama at Birmingham ), John Blundell ( University of Leeds ), Myles Faith ( University of North Carolina ), James Hill ( University of Colorado at Denver ), John Jakicic ( University of Pittsburgh ), Richard Mattes ( Purdue University ), John Peters ( University of Colorado at Denver ), Eric Ravussin ( Pennington Biomedical Research Center ), and Susan Roberts ( Jean Mayer USDA Human Nutrition Center on Aging ). All authors read and approved the concluding manuscript. All authors participated evenly in the development of the statement .

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Author notes

© 2012 American Society for Nutrition

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