The novel antiobesic HMR1426 reduces food intake without affecting energy expenditure in rats

OBJECTIVE: To determine the effect of acute and chronic administration of a new food intake-reducing compound (HMR1426) with novel mode of action (retardation of gastric emptying) on body weight development, food intake, and energy metabolism in rats. RESEARCH METHODS AND PROCEDURES: Adult male Shoe-Wistar rats were implanted with transponders allowing registration of body temperature (Tb) and locomotor activity. HMR1426 (10 or 50 mg/kg) was given orally, and acute (8 hours) and chronic (15 days) effects were measured on food intake, Tb, activity, total energy expenditure (indirect calorimetry), and epididymal adipose tissue mass. The effect of chronic treatment was compared with the effect of sibutramine (10 mg/kg). RESULTS: HMR1426 (50 mg/kg) caused an acute and chronic decrease of food intake. There was no effect on the level and daily pattern of total energy expenditure, Tb, and locomotor activity. Respiratory quotient was acutely decreased by HMR1426 due to reduced food intake. Chronic treatment with HMR1426 decreased weight gain by 31% and epididymal white fat by 24%. Sibutramine caused a respective reduction of 48% and 35%. Energy efficiency was not affected by HMR1426 in contrast to sibutramine, which reduced energy efficiency and transiently increased activity. DISCUSSION: HMR1426 showed an anorectic potential in rats and decreased body weight and fat mass. This was achieved solely by reducing food intake without influencing overall energy expenditure or behavior suggesting a peripheral mode of action. Thus, HMR1426 can be considered a potential new drug for obesity treatment.     

d-Psicose increases energy expenditure and decreases body fat accumulation in rats fed a high-sucrose diet

We investigated the anti-obesity effects of d-psicose by increasing energy expenditure in rats pair-fed the high-sucrose diet (HSD). Wistar rats were divided into two dietary groups: HSD containing 5% cellulose (C) and 5% d-psicose (P). The C dietary group was further subdivided into two groups: rats fed the C diet ad libitum (C-AD) and pair-fed the C diet along with those in the P group (C-PF). Resting energy expenditure during darkness and lipoprotein lipase activity in the soleus muscle were significantly higher in the P group than in the C-PF group. Serum levels of glucose, leptin and adiponectin; glucose-6-phosphate dehydrogenase activities in the liver and perirenal adipose tissue; and body fat accumulation were all significantly lower in the P group than in the C-PF group. The anti-obesity effects of D-psicose could be induced not only by suppressing lipogenic enzyme activity but also by increasing EE in rats.     

Adjusting energy expenditure for body weight in early infancy

The most appropriate method of expressing energy expenditure relative to body weight was investigated in 50 normal, full-term infants at 6 weeks, 12 weeks and 6 months of age. Regression analysis revealed that the relationship between body weight and energy expenditure at each age could be adjusted for by expressing energy expenditure per kg0.65, per kg0.43 and per kg0.55 body weight at the three age points studied. These powers were not significantly different and a pooled estimate was per kg0.56. This is very close to kg0.5 or the square root of body weight. It is suggested that in studies on energy, metabolism in early infancy the expression of total energy expenditure per kg0.5 body weight should be used as the most appropriate adjustment for removing the influence of body weight upon energy expenditure.     

Sibutramine decreases body weight gain and increases energy expenditure in obese Zucker rats without changes in NPY and orexins

The aim of the present work was to describe the effects of sibutramine on body weight and adiposity and to establish the potential involvement of neuropeptide Y (NPY) and orexins in the anorectic action of this drug. Male obese Zucker rats were daily administered with sibutramine (10 mg/kg, intraperitoneal) for two weeks. Carcass composition was assessed using the official methods of the Association of Official Analytical Chemists. Total body oxygen consumption was measured daily for 60 min before sibutramine or saline injection and for 30 min (from 60 to 90 min) after drug or saline injection. Hypothalamic arcuate and paraventricular nuclei, and the lateral hypothalamic area were immunostained for NPY, orexin A and orexin B. Commercial kits were used for serum determinations. Reductions in body weight and adipose tissue weights were observed after sibutramine treatment in obese Zucker rats. No changes in NPY immunostaining in the arcuate and paraventricular nuclei were found. Orexin A and orexin B immunostaining was not modified in the lateral hypothalamic area in treated rats. The reduction in body weight and adiposity induced by sibutramine was achieved by both a reduction in food intake and an increase in energy expenditure. NPY and orexins do not seem to be involved in the anorectic effect of sibutramine.     

Relation between energy expenditure and body composition in man: specific energy expenditure in vivo of fat and fat-free tissue

The relationship between energy expenditure and body composition, in terms of fat and fat-free masses, has previously been described by a variety of predictive regression equations with parameters devoid of physiological content. We present here results obtained by calculating the specific energy expenditure, ie, the energy expenditure per unit of mass, of fat and fat-free tissue on the basis of measurements of the total energy expenditure (EE), the masses of fat (FM), and fat-free (FFM) tissue using the following simple model: EE = k1.FM + k2.FFM where k1 and k2 are the specific energy expenditures of fat and fat-free tissue, respectively. The results of observations on 104 women at rest yielded values for k1 and k2 of 0.31 and 1.35 watts/kg of fat and fat-free mass, respectively, with standard errors of estimate of 0.074 and 0.052 watts/kg, respectively. Analysis of several series of measurements, from other sources and on smaller samples of subjects, yielded similar values at rest but with larger standard errors of estimate. Data from subjects performing varying amounts of work in 24-h measurements showed, as expected, larger values for both tissues. The results explain to a very large extent the well-established relation between resting metabolic rate and body weight, ie, a linear relation with a non-zero intercept. The results also offer a clear-cut explanation for the well known difference in energy expenditure between men and women with the same body weight.     

Regional lean body mass and resting energy expenditure in non-obese adults

Summary Objective To study the effect of regional lean body mass (LBM) on resting energy expenditure (REE). Design Cross-sectional study in a homogenous group of 26 young healthy non-obese subjects. Methods Regional body composition was assessed by dual-energy X-ray absorptiometry (DEXA). REE was measured by indirect calorimetry. Results REE showed positive relationships with whole body LBM (LBM_b; r=0.89) as well as with regional LBM (LBM_trunk = LBM_t, r = 0.88, and LBM_arms+legs = LBM_e for LBM_extremities, r = 0.89) with non-zero intercepts (between 1.86 and 2.83 MJ/d). REE per kg LBM_b falls as LBM_b increases (r = 0.77). By contrast, REE adjusted for regional distribution of LBM (i. e. the ratio of LBM_t to LBM_e) increases as LBM_b increases (r = 0.91) showing a near-zero intercept (i. e. 0.048 MJ/d). Adjusting REE for LBM_b as well as for the ratio of LBM_t to LBM_e can be used for comparison between subjects. Conclusions Our data suggest that regional distribution of LBM is a determinant of REE. Assessment of LBM_t and LBM_e by DEXA provides a possibility to adjust for the non-linearity of REE on LBM_b. Received: 11 April 2001, Accepted: 12 June 2001     

学龄儿童运动能量消耗与人体成分的关系

目的　探讨学龄期儿童运动能量消耗（AEE）与人体成分之间的关系。方法　以上海市杨浦区二联小学三、四年级62名学生为研究对象,使用代谢车测定运动能量消耗,利用生物电阻抗法测定人体成分,包括体质量、体质量指数、体脂率、脂肪含量、去脂体质量、脂肪含量指数、去脂体质量指数、肥胖度和AEE,比较超重肥胖组与非超重肥胖组儿童各指标的差异,并探讨其关系。结果　男生超重肥胖组和非超重肥胖组的运动时间［（9.70±1.91）min 比（10.00±1.97）min;t=0.336,P=0.739］、总AEE［（198.74±53.33）kJ 比 （171.54±41.75）kJ;t=-1.422,P=0.165］、AEE相对值［（0.46±0.09）kJ/(min·kg）比（0.51±0.04）kJ/(min·kg); t=2.043,P=0.051］差异均无统计学意义,超重肥胖组AEE绝对值高于非超重肥胖男生组［（20.06±3.14）kJ/min比（16.93±1.85）kJ/min;t=-2.910,P=0.007］。女生超重肥胖组与非超重肥胖组相比运动时间更短［（7.35±3.05）min 比 （9.98±1.82）min;t=2.509,P=0.027］、AEE相对值更小［（0.41±0.09）kJ/(min·kg）比 （0.51±0.07）kJ/(min·kg）;t=3.244,P=0.003］,但两组总AEE［（129.29±71.13）kJ 比 （161.50±35.38）kJ;t=1.351,P=0.203］、AEE绝对值［（16.82±3.26）kJ/min 比 （16.17±2.00）kJ/min; t=-0.676,P=0.504］差异均无统计学意义。控制年龄和性别因素后,男生AEE绝对值与体质量指数（P=0.015）、肥胖度(P=0.010)、脂肪含量(P=0.047)、去脂体质量(P=0.010）和去脂体质量指数(P=0.003)呈显著正相关,女生AEE绝对值与体成分各指标无相关性。AEE相对值与体质量指数（男：P=0.000,女：P=0.000）、肥胖度（男：P=0.002,女：P=0.000）、体脂率（男：P=0.000,女：P=0.001）、脂肪含量（男：P=0.000,女：P=0.000）、去脂体质量（男：P=0.002,女：P=0.022）和脂肪含量指数（男：P=0.000,女：P=0.000）呈显著负相关。结论　肥胖儿童AEE与体成分有关,肥胖程度越高,AEE相对值越少。儿童的体型、体成分与能量代谢存在着复杂的联系。     

A study of the carcinogenicity of glycidol in Syrian hamsters.

The industrial chemical glycidol is a directly acting mutagen and a broadly acting carcinogen in rats. It was administered to Syrian golden hamsters (20 male and 20 female) by gavage of 12 mg twice a week for 60 weeks. The total dose per animal was 1.45 g or 20 mmol. Survival was not different from control hamsters treated with corn oil/ethyl acetate. Of the treated males, 9 had tumors and 13 of the treated females had tumors, some of which were adrenal cortex tumors seen in controls. More tumors were seen in the glycidol-treated hamsters than in controls, but the spleen was the only notable target organ and the number of animals with spleen hemangiosarcomas was small. Glycidol appeared to be less carcinogenic in hamsters than in rats or mice.     

Total and regional body composition and energy expenditure in multiple symmetric lipomatosis

AIMS: The aim of the present study was to investigate possible alterations in body composition and resting energy expenditure (REE) in type 1 multiple symmetric lipomatosis (MSL). SUBJECTS AND METHODS: Thirteen men aged from 40 to 78 years affected by type I MSL were compared with 13 healthy control subjects. Fat mass (FM) and fat-free mass (FFM) were determined by DEXA using both standard analysis and specifically for the lipomatous region. REE was measured by indirect calorimetry. RESULTS: FM was higher in MSL subjects at proximal arm level, but significantly lower at distal leg level than in controls (left 1.63+/-0.55 vs. 2.26+/-0.49 kg, P<0.05; right 1.63+/-0.53 vs. 2.40+/-0.54 kg, P<0.01). Arm FFM was similar in the two groups, while distal leg FFM was significantly lower in MSL cases (left: 7.8+/-1.3 vs. 8.7+/-0.8 kg, P<0.05; right: 8.0+/-1.5 vs. 9.2+/-0.9 kg, P<0.05). FFM strongly correlated with REE (r:0.86;P<0.001). REE, expressed as an absolute value and adjusted for FFM (1830+/-215 vs. 1675+/-120 kcal, P<0.05) was higher in MSL patients. CONCLUSION: In conclusion, MSL patients had a marked FFM and FM atrophy in the lower segments of the legs and an altered energy expenditure (hypermetabolism).     

Intraduodenal infusion of alpha-ketoglutarate decreases whole body energy expenditure in growing pigs

BACKGROUND AND AIMS: alpha-Ketoglutarate (AKG) has been suggested to play a particular role as an oxidative fuel for the gut, and thus may have a sparing function for fuels such as glutamate and aspartate. Using the pig model we aimed to quantify how the route of administration (intravenous, i.v.; intragastric, i.g.; intraduodenal, i.d.) affects AKG utilization, whole body energy expenditure (EE) and nutrient oxidation. METHODS: Pigs (15 kg) were supplied with a complete nutrient solution (NS) via catheters. To explore the metabolic effects of AKG, 1.0 g AKG kgBW(-1)d(-1) was infused simultaneously with the NS using either the i.d., i.v. or i.g. route. [1-(13)C]AKG (15 mg kgBW(-1)) was infused i.d., i.v. or i.g., respectively, for 3h. AKG utilization (AKG UTIL) was estimated as AKG UTIL=100-(13)C recovery (% of (13)C dose). (13)C recovery was calculated from the (13)C enrichment in breath CO(2) and the whole-body CO(2) production. RESULTS: AKG infusion and NS via the i.d. route resulted in a reduced AKG UTIL (40.1+/-6.7) as compared to the i.v. route (62.9+/-2.4, P<0.001) and i.g. route (62.3+/-1.6, P<0.001). The total EE was lower with the i.d. route of AKG and NS (745+/-68 kJkgBW(-0.62)d(-1)) as compared to the i.v. route (965+/-54 kJkgBW(-0.62)d(-1), P<0.005) and i.g. route (918+/-43 kJkgBW(-0.62)d(-1), P<0.005). Carbohydrate oxidation was increased with the i.d. route (38.2g+/-3.4 kgBW(-0.62)d(-1)) as compared to the i.v. route (27.8+/-2.9 gkgBW(-0.62)d(-1), P<0.08) and i.g. route (23.9+/-8.5 gkgBW(-0.62)d(-1), P<0.05). Fat oxidation was decreased (2.1+/-1.9 gkgBW(-0.62)d(-1); P<0.001) with the i.d. route as compared to the i.v. route (11.5+/-1.4 gkgBW(-0.62)d(-1), P<0.001) and i.g. route (11.9+/-3.1 gkgBW(-0.62)d(-1), P<0.001). CONCLUSIONS: The i.d. infusion of AKG in combination with the NS affected the whole body EE and nutrient oxidation, in comparison to that obtained with the i.v. and i.g. routes. It was concluded that the i.d. administration of AKG markedly controlled the nutrient partitioning in the oxidation processes. Finally, in contrary to the observations with glutamine or glutamate, a considerable percentage of the AKG infusion was retained in the body irrespective of the route of administration.     

Characteristics of body composition and resting energy expenditure in lean young women

The number of lean young women has been increasing. Fear of being fat may induce unnecessary attempts to reduce body weight, which can cause several types of illness. Many investigations have demonstrated dysfunction of the hypothalamus and metabolic differences in patients with anorexia nervosa. However, it is unclear whether there are any differences in physical characteristics between women with lower body weight and no illness compared to those of normal body weight. In this study, we investigated the differences in body composition, biochemical parameters, and resting energy expenditure (REE) between young women with low and normal body mass index (BMI). Twenty lean women (BMI<18.5 kg/m(2)) and 20 normal women (18.5≤BMI<25 kg/m(2)) were recruited for this study. Body composition, biochemical parameters, and REE (REEm: measurement of REE) were measured, and the REE (REEe: estimation of REE) was estimated by using a prediction model. Marked differences were found in body composition. All of the values of blood analysis were in the normal ranges in both groups. REEm (kcal/d and kcal/kg BW/d) was significantly lower in lean than in normal women, but there were no significant differences in the REEm to fat free mass (FFM) ratio between the two groups. In addition, there was good agreement between REEm and REEe obtained from the specific metabolic rates of four tissue organs. These data indicate that the lean women without any illness have normal values of biochemical parameters and energy metabolism compared to women with normal BMI.     

Involvement of prostaglandin A1 in interrupting early pregnancy in Syrian golden hamsters

The effects of a single administration of authentic prostaglandin A1 intravaginally in early pregnant hamsters were investigated. A single dose of 1 mcg/animal given on day 4 of pregnancy inhibited the appearance of embryonic swellings when observed on day 8 of pregnancy. A significant fall (p<0.01) in FSH with a rise (p<0.03) in prolactin concentration in the serum and no change in LH levels were observed. The pituitary content of prolactin showed a significant decrease (p<0.0006) with no change in FSH and LH contents.Progesterone concentration in the serum was markedly reduced (p<0.002), along with that of the ovaries (p<0.01). The decline in progesterone concentration coincided with the absence of corpora lutea and the embryos. However, no change in ovarian weights was observed. These results indicate the contragestive potential of prostaglandin A1. It appears to act as a luteolytic agent by disrupting the luteotropic complex (FSH:prolactin ratio).

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Resumen Se investigaron los efectos de una administración intravaginal de prostaglandina A1 en hamsters con embarazo temprano. Una sola dosis de 1 mcg/animal al 4° día del embarazo (P) inhibió la aparición de los edemas embriónicos cuando se los observó en el 8° día del embarazo. Se notó una caída significativa (p<0,01) en FSH con un aumento (p<0,03) en la concentración de prolactina y ningun cambio en los niveles de LH. E1 contenido de prolactina en la pituitaria mostró una disminución significativa (p<0,0006) sin cambios en los niveles de FSH y LH.La concentración de progesterona en suero estuvo notablemente reducida (p<0,002) asi como la de los ovarios (p<0,01). La disminución en la concentración de progesterona coincidió con la ausencia de cuerpo lúteo y de embriones. Sin embargo, no se observó cambio en el peso ovárico. Estos resultados indican el potencial antigestante de la prostaglandina A1. Esta parece actuar como agente luteolítico, interrumpiendo el complejo luteotrópico (relación FSH:prolactina).

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Resumé On a étudié les effets de l'administration par voie intravaginale d'une dose unique de prostaglandine A1 à des hamsters au début de la gestation. On a constaté au huitième jour qu'une dose unique de 1 mcg par animal, administrée au quatrième jour de gestation, avait inhibé l'apparition des grosseurs embryonnaires. On a constaté en outre une baisse significative (p<0,01) de l'HSF, avec une augmentation (p<0,03) de la concentration de prolactine sérique, mais aucun changement dans les niveaux de l'HL. La teneur en prolactine retrouvée dans l'hypophyse présentait une biasse significative (p<0,0006), sans qu'il y ait eu de changement dans la teneur en HSF et HL. En outre, la concentration de progestérone dans le sérum et dans les ovaires était sensiblement réduite (respectivementp<0,002 etp<0,01). La baisse de la concentration de progestérone concidait avec l'absence de corps jaune et d'embryon. Aucune modification du poids des ovaires n'a cependant été observée. Ces résultats font apparaitre le potentiel de la prostagladine A1 en tant qu'agent inhibiteur de la gestation. Son action semble être celle d'un agent lutéolytique qui perturbe le complexe lutéotrope. (HSF: proportion de prolactine)

     

Plasma leptin association with body composition and energy expenditure in sickle cell disease

OBJECTIVE: To examine the association between fasting plasma leptin concentrations and the hypercatabolic state observed in sickle cell disease (SCD). METHODS: Plasma leptin concentration and resting energy expenditure (REE) were measured in 37 SCD patients (10 men, 12 boys 14 to 18 years-old, seven women, and eight girls 14 to 18 year-old) and in 37 age, gender and fat mass (FM) matched controls. Body composition was measured hydrostatically, REE by whole room-indirect calorimeter, and plasma leptin using an RIA kit. RESULTS: Plasma leptin concentration and leptin normalized for body fat (ng/dL*kg FM(-1)) were significantly lower in SCD patients than in non-SCD controls (4.00+/-3.23 vs. 9.94+/-14.69, p=0.021 and 0.406+/-0.260 vs. 0.643+/-0.561, p=0.024, respectively). A positive linear association between log plasma leptin and FM was observed in both males and females, adjusting for age and SCD status. The strength of this association was greater in females compared with males (slope=0.699 and 0.382 log ng/mL per 10 kg FM, respectively; p=0.013). SCD patients on average demonstrated a higher REE, adjusting for FFM (p<0.0001). Log plasma leptin and FM were not statistically significant predictors of REE after adjustment for FFM and SCD. CONCLUSIONS: Once corrected for body composition, mean plasma leptin concentration was significantly lower among female SCD patients than among non-SCD matched controls. Although REE was higher in SCD patients, there is no simple association between leptin and REE in SCD.     

Free-living activity energy expenditure in women successful and unsuccessful at maintaining a normal body weight

BACKGROUND: Although physical inactivity is believed to contribute to the rising prevalence of obesity, the role and magnitude of its contribution to weight gain are unknown. OBJECTIVE: We compared total free-living activity energy expenditure (AEE) and physical activity level in women successful and unsuccessful at maintaining a normal body weight. DESIGN: Premenopausal, generally sedentary women were studied at their normal weight and 1 y later after no intervention. Two groups were identified on the basis of extreme weight changes: maintainers (n = 27) had a weight gain of less-than-or-equal 3% of their initial body weight ( less-than-or-equal 2 kg/y) and gainers (n = 20) had a weight gain of >10% (>6 kg/y). At baseline and follow-up, evaluations were conducted during 4 wk of diet-controlled, energy-balance conditions. Free-living AEE and physical activity were assessed with the use of doubly labeled water, exercise energy economy and muscle strength with the use of standardized exercise tests, and sleeping EE and substrate utilization with the use of chamber calorimetry. RESULTS: Maintainers lost a mean (plus minusSD) of 0.5 plus minus 2.2 kg/y and gainers gained 9.5 plus minus 2.1 kg/y. Gainers had a lower AEE (P < 0.02), a lower physical activity level (P < 0.01), and less muscle strength (P < 0.001); these differences between groups remained significant from baseline to follow-up. Sleeping EE, exercise economy, and sleeping or 24-h substrate utilization were not significantly different between the 2 groups. A lower AEE in the gainers explained approximately 77% of their greater weight gain after 1 y. CONCLUSION: The general US population should increase their daily physical activity levels to decrease the rising prevalence of obesity.     

A longitudinal study of resting energy expenditure relative to body composition during puberty in African American and white children

BACKGROUND: Body composition and resting energy expenditure (REE) have not been examined longitudinally during puberty. OBJECTIVE: The purpose of this longitudinal study was to examine the influence of pubertal maturation on REE relative to body composition in African American and white children. DESIGN: The study included 92 white and 64 African American children (mean age at baseline: 8.3 and 7.9 y, respectively) from Birmingham, AL. The children had 2-5 annual measurements of fat mass (FM), lean mass (LM), and REE. The Tanner stages of the children ranged from 1 to 5. Mixed-model repeated-measures analyses were used to test the change in REE relative to body composition with increasing Tanner stage among ethnic and sex groups. RESULTS: LM increased from Tanner stage 1 to subsequent stages. FM relative to LM decreased from Tanner stage 1 to stages 3, 4, and 5 but not from stage 1 to stage 2. The African American children had relatively higher limb LM and lower trunk LM than did the white children. REE declined with Tanner stage after adjustment for ethnicity, sex, FM, and LM. This decline was significant from Tanner stage 1 to stages 3, 4, and 5 but not to Tanner stage 2. After adjustment for age, Tanner stage, FM, and LM or LM distribution, REE was significantly higher in white than in African American children (by approximately 250 kJ/d). CONCLUSION: In a large sample of children at various Tanner stages, we found an ethnic difference in REE after adjustment for age, Tanner stage, FM, and LM that was not explained by the difference in LM distribution.     

Intra-individual variability and measurement noise in estimates of energy expenditure by whole body indirect calorimetry

1. Four men were each studied continuously over 12 d in a whole-body calorimeter. Dietary intake and daily activities were kept constant throughout the study. 2. Day-to-day coefficients of variation in energy expenditure within subjects were found to be 1.97% over 24 h, 5.93% during basal metabolic rate measurement, 2.40% overnight and 3.22% in exercise. 3. The contribution of measurement system noise to the observed variability was analysed and shown to be generally small. The source of this noise was considered. 4. The results reinforce and extend other comparable reports and show that within-subject variability forms a small part of reported observations of between-subject variability.     

Influence of methods used in body composition analysis on the prediction of resting energy expenditure

OBJECTIVE: There are considerable differences in published prediction algorithms for resting energy expenditure (REE) based on fat-free mass (FFM). The aim of the study was to investigate the influence of the methodology of body composition analysis on the prediction of REE from FFM. DESIGN: In a cross-sectional design measurements of REE and body composition were performed. SUBJECTS: The study population consisted of 50 men (age 37.1+/-15.1 years, body mass index (BMI) 25.9+/-4.1 kg/m2) and 54 women (age 35.3+/-15.4 years, BMI 25.5+/-4.4 kg/m2). INTERVENTIONS: REE was measured by indirect calorimetry and predicted by either FFM or body weight. Measurement of FFM was performed by methods based on a 2-compartment (2C)-model: skinfold (SF)-measurement, bioelectrical impedance analysis (BIA), Dual X-ray absorptiometry (DXA), air displacement plethysmography (ADP) and deuterium oxide dilution (D2O). A 4-compartment (4C)-model was used as a reference. RESULTS: When compared with the 4C-model, REE prediction from FFM obtained from the 2C methods were not significantly different. Intercepts of the regression equations of REE prediction by FFM differed from 1231 (FFM(ADP)) to 1645 kJ/24 h (FFM(SF)) and the slopes ranged between 100.3 kJ (FFM(SF)) and 108.1 kJ/FFM (kg) (FFM(ADP)). In a normal range of FFM, REE predicted from FFM by different methods showed only small differences. The variance in REE explained by FFM varied from 69% (FFM(BIA)) to 75% (FFM(DXA)) and was only 46% for body weight. CONCLUSION: Differences in slopes and intercepts of the regression lines between REE and FFM depended on the methods used for body composition analysis. However, the differences in prediction of REE are small and do not explain the large differences in the results obtained from published FFM-based REE prediction equations and therefore imply a population- and/or investigator specificity of algorithms for REE prediction.