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Effects of inulin supplementation on body composition and metabolic outcomes in children with obesity.
Visuthranukul, C, Chamni, S, Kwanbunbumpen, T, Saengpanit, P, Chongpison, Y, Tepaamorndech, S, Panichsillaphakit, E, Uaariyapanichkul, J, Nonpat, N, Chomtho, S
Scientific reports. 2022;12(1):13014
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The prevalence of overweight and obesity among children and adolescents has risen dramatically. Overweight and obese children are at risk of developing co-morbidities such as type 2 diabetes mellitus, hypertension, dyslipidaemia, metabolic syndrome, non-alcohol fatty liver disease and premature cardiovascular diseases. Furthermore, obese children are highly prone to become obese adults. The aim of this study was to determine the effects of prebiotic (as inulin) supplementation on body weight, adiposity, and metabolic profiles in obese Thai children. This study is a randomised double-blinded placebo-controlled trial. Participants (n=165) were randomly allocated to 3 groups: inulin, placebo, and dietary fibre advice group. Results show that the intensive behavioural modification and frequent follow-up are effective strategies to reduce body mass index and adiposity in obese children. Furthermore, even though inulin supplementation did not demonstrate considerable effect on adiposity and metabolic outcomes, it can increase fat-free mass in these children. Authors conclude that further research regarding the change of gut microbiota composition and their metabolites are needed to determine inulin’s impact on host microbe interaction in obese paediatric population.
Abstract
Inulin might improve body composition in obese children. We aimed to determine the effects of inulin supplementation on body composition and metabolic outcomes in obese children. A randomized, double-blinded placebo-controlled study was conducted in obese Thai children aged 7-15 years. Participants were assigned to 3 treatment groups for 6 months: 13 g of extracted inulin powder from Thai Jerusalem artichoke, isocaloric maltodextrin, and dietary fiber advice groups. Body composition was assessed by bioelectrical impedance analysis. One-hundred and fifty-five children completed the study (mean age 10.4 ± 2.2 years, BMI z-score 3.2 ± 1.0, 59% male). The drop-out rate was 6%. The inulin extract yielded more than 90% compliance without significant gastrointestinal side effects. All three groups demonstrated a significant decrease in BMI z-score, fat mass index (FMI), and trunk FMI, but the differences between groups were not observed. Fat-free mass index significantly increased only in the inulin group (16.18 ± 1.90 vs. 16.38 ± 1.98 kg/m2, P = 0.009). There were no significant differences in the metabolic profiles between groups. Despite showing no substantial effect on adiposity, inulin may increase fat-free mass in obese children. Further research in the change of gut microbiota composition is needed to determine inulin's impact on host-microbe interaction in pediatric obesity.
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Influence of timing of maternal antibiotic administration during caesarean section on infant microbial colonisation: a randomised controlled trial.
Dierikx, T, Berkhout, D, Eck, A, Tims, S, van Limbergen, J, Visser, D, de Boer, M, de Boer, N, Touw, D, Benninga, M, et al
Gut. 2022;71(9):1803-1811
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Early-life microbiome acquisition and development can be compromised by external perturbations such as delivery via caesarean section (CS), formula feeding and antibiotics. Currently, based on revised international guidelines, all infants born by CS are exposed to broad-spectrum antibiotics via the umbilical cord. Even though there was not an increase in the incidence of neonatal sepsis, the effects on the gut microbiota colonisation and long-term health consequences remain largely unknown. The hypothesis for this study was that exposure to antibiotics in children delivered by CS, related to the revised international guidelines, influences the microbial colonisation process and may impact health outcome. This study is a randomised controlled trial on the microbiome and health state of infants up to 3 years of age. The study enrolled women delivering via CS who received antibiotics prior to skin incision (n=20) or after umbilical cord clamping (n=20) and women who had a vaginal delivery (n=23). Results show that CS delivery in general leads to a profound impact on the initial microbial colonisation. Furthermore, maternal antibiotic administration prior to CS does not lead to a ‘second hit’ on the already compromised microbiome in CS born infants. Authors conclude that early-life microbiome development is strongly affected by mode of delivery.
Abstract
OBJECTIVE Revised guidelines for caesarean section (CS) advise maternal antibiotic administration prior to skin incision instead of after umbilical cord clamping, unintentionally exposing the infant to antibiotics antenatally. We aimed to investigate if timing of intrapartum antibiotics contributes to the impairment of microbiota colonisation in CS born infants. DESIGN In this randomised controlled trial, women delivering via CS received antibiotics prior to skin incision (n=20) or after umbilical cord clamping (n=20). A third control group of vaginally delivering women (n=23) was included. Faecal microbiota was determined from all infants at 1, 7 and 28 days after birth and at 3 years by 16S rRNA gene sequencing and whole-metagenome shotgun sequencing. RESULTS Compared with vaginally born infants, profound differences were found in microbial diversity and composition in both CS groups in the first month of life. A decreased abundance in species belonging to the genera Bacteroides and Bifidobacterium was found with a concurrent increase in members belonging to the phylum Proteobacteria. These differences could not be observed at 3 years of age. No statistically significant differences were observed in taxonomic and functional composition of the microbiome between both CS groups at any of the time points. CONCLUSION We confirmed that microbiome colonisation is strongly affected by CS delivery. Our findings suggest that maternal antibiotic administration prior to CS does not result in a second hit on the compromised microbiome. Future, larger studies should confirm that antenatal antibiotic exposure in CS born infants does not aggravate colonisation impairment and impact long-term health.
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Probiotic Supplementation Improves Cognitive Function and Mood with Changes in Gut Microbiota in Community-Dwelling Older Adults: A Randomized, Double-Blind, Placebo-Controlled, Multicenter Trial.
Kim, CS, Cha, L, Sim, M, Jung, S, Chun, WY, Baik, HW, Shin, DM
The journals of gerontology. Series A, Biological sciences and medical sciences. 2021;76(1):32-40
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Aging is characterized by progressive decline in biological functions of the organism. Diet is one of the critical lifestyle factors for physical and mental well-being throughout the life span, including later life. The aim of this study was to investigate the effects of probiotics consumption on intestinal and brain health in elders over the age of 65. This study is a randomised, double-blind, placebo-controlled, multicentre trial. All participants, study coordinators, and researchers were blinded throughout the entire study. Sixty-three participants were randomized, with 31 and 32 subjects in the placebo and probiotics group, respectively. Results demonstrate that probiotics have system-wide effects on the gut–brain axis in healthy community-dwelling older adults by promoting cognitive and mental health and changing the gut microbial composition. Authors conclude that their findings provide evidence that probiotics have health-promoting properties as part of a healthy diet in the general population of independently living older adults.
Abstract
Probiotics have been proposed to ameliorate cognitive impairment and depressive disorder via the gut-brain axis in patients and experimental animal models. However, the beneficial role of probiotics in brain functions of healthy older adults remains unclear. Therefore, a randomized, double-blind, and placebo-controlled multicenter trial was conducted to determine the effects of probiotics on cognition and mood in community-dwelling older adults. Sixty-three healthy elders (≥65 years) consumed either placebo or probiotics containing Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI for 12 weeks. The gut microbiota was analyzed using 16S rRNA sequencing and bioinformatics. Brain functions were measured using the Consortium to Establish a Registry for Alzheimer's disease, Satisfaction with life scale, stress questionnaire, Geriatric depression scale, and Positive affect and negative affect schedule. Blood brain-derived neurotrophic factor (BDNF) was determined using enzyme-linked immunosorbent assay. Relative abundance of inflammation-causing gut bacteria was significantly reduced at Week 12 in the probiotics group (p < .05). The probiotics group showed greater improvement in mental flexibility test and stress score than the placebo group (p < .05). Contrary to placebo, probiotics significantly increased serum BDNF level (p < .05). Notably, the gut microbes significantly shifted by probiotics (Eubacterium and Clostridiales) showed significant negative correlation with serum BDNF level only in the probiotics group (RS = -0.37, RS = -0.39, p < .05). In conclusion, probiotics promote mental flexibility and alleviate stress in healthy older adults, along with causing changes in gut microbiota. These results provide evidence supporting health-promoting properties of probiotics as a part of healthy diet in the older adults.
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Dietary supplementation with inulin-propionate ester or inulin improves insulin sensitivity in adults with overweight and obesity with distinct effects on the gut microbiota, plasma metabolome and systemic inflammatory responses: a randomised cross-over trial.
Chambers, ES, Byrne, CS, Morrison, DJ, Murphy, KG, Preston, T, Tedford, C, Garcia-Perez, I, Fountana, S, Serrano-Contreras, JI, Holmes, E, et al
Gut. 2019;68(8):1430-1438
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Literature shows that higher intakes of dietary fibre are associated with a reduced risk of type 2 diabetes. The main aim of this study was to elucidate the underlying mechanisms behind improvements in glucose homeostasis following long-term delivery of propionate (a short-chain fatty acid produced by human gut microbiota in response to dietary fibre) to the human colon. The study is a randomised, double-blind, placebo-controlled cross over trial. Fourteen participants randomly received 20 g/day of a low-fermentable fibre control, a high-fermentable fibre control and inulin-propionate ester (IPE) for 42 days each. Results indicate that stool concentrations of short-chain fatty acids were not different following the three supplementation periods. Furthermore, dietary supplementation with 20 g/day IPE promoted no superior impacts on measures of glucose homeostasis compared with inulin (high-fermentable fibre), yet both IPE and inulin improved insulin resistance relative to cellulose (low-fermentable fibre). Authors conclude that manipulating the colonic fermentation profile of a dietary fibre in favour of propionate promotes selective effects on the mechanisms that contribute to metabolic dysregulation.
Abstract
OBJECTIVE To investigate the underlying mechanisms behind changes in glucose homeostasis with delivery of propionate to the human colon by comprehensive and coordinated analysis of gut bacterial composition, plasma metabolome and immune responses. DESIGN Twelve non-diabetic adults with overweight and obesity received 20 g/day of inulin-propionate ester (IPE), designed to selectively deliver propionate to the colon, a high-fermentable fibre control (inulin) and a low-fermentable fibre control (cellulose) in a randomised, double-blind, placebo-controlled, cross-over design. Outcome measurements of metabolic responses, inflammatory markers and gut bacterial composition were analysed at the end of each 42-day supplementation period. RESULTS Both IPE and inulin supplementation improved insulin resistance compared with cellulose supplementation, measured by homeostatic model assessment 2 (mean±SEM 1.23±0.17 IPE vs 1.59±0.17 cellulose, p=0.001; 1.17±0.15 inulin vs 1.59±0.17 cellulose, p=0.009), with no differences between IPE and inulin (p=0.272). Fasting insulin was only associated positively with plasma tyrosine and negatively with plasma glycine following inulin supplementation. IPE supplementation decreased proinflammatory interleukin-8 levels compared with cellulose, while inulin had no impact on the systemic inflammatory markers studied. Inulin promoted changes in gut bacterial populations at the class level (increased Actinobacteria and decreased Clostridia) and order level (decreased Clostridiales) compared with cellulose, with small differences at the species level observed between IPE and cellulose. CONCLUSION These data demonstrate a distinctive physiological impact of raising colonic propionate delivery in humans, as improvements in insulin sensitivity promoted by IPE and inulin were accompanied with different effects on the plasma metabolome, gut bacterial populations and markers of systemic inflammation.
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Role of whole grains versus fruits and vegetables in reducing subclinical inflammation and promoting gastrointestinal health in individuals affected by overweight and obesity: a randomized controlled trial.
Kopf, JC, Suhr, MJ, Clarke, J, Eyun, SI, Riethoven, JM, Ramer-Tait, AE, Rose, DJ
Nutrition journal. 2018;17(1):72
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Poor diet is the leading risk factor for premature death and disability in the United States. Poor diets lead to metabolic syndrome and its associated diseases such as heart disease and diabetes. The purpose of this study was to determine the impact of increasing intake of wholegrains or fruit and vegetables against a typical Western diet on inflammatory makers and gut microbiota composition. The study was a randomized, parallel arm feeding trial which enrolled fifty-two participants. The subjects were randomized into three groups (control, wholegrains, and fruit and vegetables). Results indicate that the wholegrain and fruit and vegetable diets had significant positive impacts on inflammatory markers. Interestingly, while both treatment groups decreased inflammatory markers, each decreased a different biomarker. The treatments induced individualised changes in microbiota composition such that treatment group differences were not identified. Authors conclude that wholegrain and fruit and vegetable diets have a positive impact on metabolic health in individuals affected by overweight or obesity.
Abstract
BACKGROUND Whole grains (WG) and fruits and vegetables (FV) have been shown to reduce the risk of metabolic disease, possibly via modulation of the gut microbiota. The purpose of this study was to determine the impact of increasing intake of either WG or FV on inflammatory markers and gut microbiota composition. METHODS A randomized parallel arm feeding trial was completed on forty-nine subjects with overweight or obesity and low intakes of FV and WG. Individuals were randomized into three groups (3 servings/d provided): WG, FV, and a control (refined grains). Stool and blood samples were collected at the beginning of the study and after 6 weeks. Inflammatory markers [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), lipopolysaccharide binding protein (LBP), and high sensitivity C-reactive protein (hs-CRP)] were measured. Stool sample analysis included short/branched chain fatty acids (S/BCFA) and microbiota composition. RESULTS There was a significant decrease in LBP for participants on the WG (- 0.2 μg/mL, p = 0.02) and FV (- 0.2 μg/mL, p = 0.005) diets, with no change in those on the control diet (0.1 μg/mL, p = 0.08). The FV diet induced a significant change in IL-6 (- 1.5 pg/mL, p = 0.006), but no significant change was observed for the other treatments (control, - 0.009 pg/mL, p = 0.99; WG, - 0.29, p = 0.68). The WG diet resulted in a significant decrease in TNF-α (- 3.7 pg/mL; p < 0.001), whereas no significant effects were found for those on the other diets (control, - 0.6 pg/mL, p = 0.6; FV, - 1.4 pg/mL, p = 0.2). The treatments induced individualized changes in microbiota composition such that treatment group differences were not identified, except for a significant increase in α-diversity in the FV group. The proportions of Clostridiales (Firmicutes phylum) at baseline were correlated with the magnitude of change in LBP during the study. CONCLUSIONS These data demonstrate that WG and FV intake can have positive effects on metabolic health; however, different markers of inflammation were reduced on each diet suggesting that the anti-inflammatory effects were facilitated via different mechanisms. The anti-inflammatory effects were not related to changes in gut microbiota composition during the intervention, but were correlated with microbiota composition at baseline. TRIAL REGISTRATION ClinicalTrials.gov , NCT02602496 , Nov 4, 2017.
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Timing of food intake predicts weight loss effectiveness.
Garaulet, M, Gómez-Abellán, P, Alburquerque-Béjar, JJ, Lee, YC, Ordovás, JM, Scheer, FA
International journal of obesity (2005). 2013;37(4):604-11
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As obesity is a multifactorial disease, dietary interventions must take into account a range of physiological and psychological variables. There is emerging evidence linking energy regulation to the circadian clock, emphasizing that the timing of eating may play a role in weight regulation. The aim of this study was to evaluate the role of food timing in weight loss effectiveness among 420 overweight or obese participants during a 20-week weight loss treatment. Participants were grouped as either early or late eaters for consuming their main meal, and their energy intake, expenditure, appetite hormones, CLOCK genotype, sleep duration and chronotype were studied. In this study, those who ate their main meal late lost significantly less weight than early eaters. The findings of this study indicate that timing of food intake relates to long-term weight loss effectiveness in humans. These findings may help in developing therapeutic strategies for weight loss that incorporates the timing of food consumption with the traditional energy balance and macronutrient composition.
Abstract
BACKGROUND There is emerging literature demonstrating a relationship between the timing of feeding and weight regulation in animals. However, whether the timing of food intake influences the success of a weight-loss diet in humans is unknown. OBJECTIVE To evaluate the role of food timing in weight-loss effectiveness in a sample of 420 individuals who followed a 20-week weight-loss treatment. METHODS Participants (49.5% female subjects; age (mean ± s.d.): 42 ± 11 years; BMI: 31.4 ± 5.4 kg m(-2)) were grouped in early eaters and late eaters, according to the timing of the main meal (lunch in this Mediterranean population). 51% of the subjects were early eaters and 49% were late eaters (lunch time before and after 1500 hours, respectively), energy intake and expenditure, appetite hormones, CLOCK genotype, sleep duration and chronotype were studied. RESULTS Late lunch eaters lost less weight and displayed a slower weight-loss rate during the 20 weeks of treatment than early eaters (P=0.002). Surprisingly, energy intake, dietary composition, estimated energy expenditure, appetite hormones and sleep duration was similar between both groups. Nevertheless, late eaters were more evening types, had less energetic breakfasts and skipped breakfast more frequently that early eaters (all; P<0.05). CLOCK rs4580704 single nucleotide polymorphism (SNP) associated with the timing of the main meal (P=0.015) with a higher frequency of minor allele (C) carriers among the late eaters (P=0.041). Neither sleep duration, nor CLOCK SNPs or morning/evening chronotype was independently associated with weight loss (all; P>0.05). CONCLUSIONS Eating late may influence the success of weight-loss therapy. Novel therapeutic strategies should incorporate not only the caloric intake and macronutrient distribution - as is classically done - but also the timing of food.
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Effects of oral ingestion of sucralose on gut hormone response and appetite in healthy normal-weight subjects.
Ford, HE, Peters, V, Martin, NM, Sleeth, ML, Ghatei, MA, Frost, GS, Bloom, SR
European journal of clinical nutrition. 2011;65(4):508-13
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There have been significant advances in the understanding of how hormonal signals released from the gastrointestinal (GI) tract interact with circuits within the central nervous system to control appetite and energy intake. The aim of this study is to investigate whether oral ingestion of sucralose, at a dose that would be consumed in a normal diet, increases circulating gut hormones (glucagon-like peptide [GLP-1] or peptide YY [PYY] concentrations in man. This study is a randomised, single-blinded, crossover design study. Subjects were randomly assigned to receive one of four solutions on four separate study sessions. Eight normal-weight, healthy volunteers were recruited, all of which were non-smokers, aged 22–27 years (seven females and one male) with a stable body weight. Results indicate that oral ingestion of the artificial sweetener sucralose does not increase plasma GLP-1 or PYY concentrations nor does it affect subjective feelings of appetite or energy intake at the next meal in healthy volunteers. Based on their findings, authors conclude that a dietary dose of sucralose does not stimulate the sweet-taste receptor in the GI tract to release GLP-1 and PYY.
Abstract
BACKGROUND/OBJECTIVE The sweet-taste receptor (T1r2+T1r3) is expressed by enteroendocrine L-cells throughout the gastrointestinal tract. Application of sucralose (a non-calorific, non-metabolisable sweetener) to L-cells in vitro stimulates glucagon-like peptide (GLP)-1 secretion, an effect that is inhibited with co-administration of a T1r2+T1r3 inhibitor. We conducted a randomised, single-blinded, crossover study in eight healthy subjects to investigate whether oral ingestion of sucralose could stimulate L-cell-derived GLP-1 and peptide YY (PYY) release in vivo. METHODS Fasted subjects were studied on 4 study days in random order. Subjects consumed 50 ml of either water, sucralose (0.083% w/v), a non-sweet, glucose-polymer matched for sweetness with sucralose addition (50% w/v maltodextrin+0.083% sucralose) or a modified sham-feeding protocol (MSF=oral stimulation) of sucralose (0.083% w/v). Appetite ratings and plasma GLP-1, PYY, insulin and glucose were measured at regular time points for 120 min. At 120 min, energy intake at a buffet meal was measured. RESULTS Sucralose ingestion did not increase plasma GLP-1 or PYY. MSF of sucralose did not elicit a cephalic phase response for insulin or GLP-1. Maltodextrin ingestion significantly increased insulin and glucose compared with water (P<0.001). Appetite ratings and energy intake were similar for all groups. CONCLUSIONS At this dose, oral ingestion of sucralose does not increase plasma GLP-1 or PYY concentrations and hence, does not reduce appetite in healthy subjects. Oral stimulation with sucralose had no effect on GLP-1, insulin or appetite.
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Diets with high or low protein content and glycemic index for weight-loss maintenance.
Larsen, TM, Dalskov, SM, van Baak, M, Jebb, SA, Papadaki, A, Pfeiffer, AF, Martinez, JA, Handjieva-Darlenska, T, Kunešová, M, Pihlsgård, M, et al
The New England journal of medicine. 2010;363(22):2102-13
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The recommended diet composition for best preventing and managing obesity has remained inconclusive. The aim of this trial is to test the efficacy of moderate fat diets that vary in protein content and glycaemic index for preventing weight regain after weight loss. After completing an 8-week low calorie diet, participants were assigned to a low protein and low-glycaemic-index diet, a low-protein and high-glycaemic-index diet, a high-protein and low-glycaemic index diet, a high-protein and high-glycaemic-index diet or a control diet. A total of 548 participants adhered to and completed the 26-week intervention following the 8-week intensive weight loss programme. This study found that participants assigned to the high-protein and low-glycaemic index diet maintained the initial weight loss and had a higher rate of completion compared with the other diets. The authors conclude that this diet composition appears to be ideal for prevention of weight regain in obese patients following successful weight loss.
Abstract
BACKGROUND Studies of weight-control diets that are high in protein or low in glycemic index have reached varied conclusions, probably owing to the fact that the studies had insufficient power. METHODS We enrolled overweight adults from eight European countries who had lost at least 8% of their initial body weight with a 3.3-MJ (800-kcal) low-calorie diet. Participants were randomly assigned, in a two-by-two factorial design, to one of five ad libitum diets to prevent weight regain over a 26-week period: a low-protein and low-glycemic-index diet, a low-protein and high-glycemic-index diet, a high-protein and low-glycemic-index diet, a high-protein and high-glycemic-index diet, or a control diet. RESULTS A total of 1209 adults were screened (mean age, 41 years; body-mass index [the weight in kilograms divided by the square of the height in meters], 34), of whom 938 entered the low-calorie-diet phase of the study. A total of 773 participants who completed that phase were randomly assigned to one of the five maintenance diets; 548 completed the intervention (71%). Fewer participants in the high-protein and the low-glycemic-index groups than in the low-protein-high-glycemic-index group dropped out of the study (26.4% and 25.6%, respectively, vs. 37.4%; P=0.02 and P=0.01 for the respective comparisons). The mean initial weight loss with the low-calorie diet was 11.0 kg. In the analysis of participants who completed the study, only the low-protein-high-glycemic-index diet was associated with subsequent significant weight regain (1.67 kg; 95% confidence interval [CI], 0.48 to 2.87). In an intention-to-treat analysis, the weight regain was 0.93 kg less (95% CI, 0.31 to 1.55) in the groups assigned to a high-protein diet than in those assigned to a low-protein diet (P=0.003) and 0.95 kg less (95% CI, 0.33 to 1.57) in the groups assigned to a low-glycemic-index diet than in those assigned to a high-glycemic-index diet (P=0.003). The analysis involving participants who completed the intervention produced similar results. The groups did not differ significantly with respect to diet-related adverse events. CONCLUSIONS In this large European study, a modest increase in protein content and a modest reduction in the glycemic index led to an improvement in study completion and maintenance of weight loss. (Funded by the European Commission; ClinicalTrials.gov number, NCT00390637.).
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Hormonal and psychobehavioral predictors of weight loss in response to a short-term weight reduction program in obese women.
Hainer, V, Hlavatá, K, Gojová, M, Kunešová, M, Wagenknecht, M, Kopský, V, Pařízková, J, Hill, M, Nedvídková, J
Physiological research. 2008;57 Suppl 1:S17-S27
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Among the many factors that influence weight loss and weight management, metabolic and hormonal parameters have been increasingly explored as important predictors. The aim of this study was to reveal potential psycho-behavioural and hormonal factors as predictors of weight loss. A group of 67 overweight women were enrolled in a 3-week weight management programme in which food intake and physical activity were under strict control. This study indicated that a short-term weight management programme induced favourable changes in anthropometric, psycho-behavioural and hormonal indices. Changes in several hormone concentrations were significantly associated with the reduction of anthropometric parameters, however psycho-behavioural factors did not contribute to weight change in the programme.
Abstract
Among the factors influencing weight loss and maintenance, psychobehavioral, nutritional, metabolic, hormonal and hereditary predictors play an important role. Psychobehavioral factors influence adherence to lifestyle changes and thus weight loss maintenance. The outcome of short-term weight reduction treatment is mainly affected by changes in energy and nutrient intake and physical activity and thus the impact of hormones can possibly be obscured. In order to reveal hormonal determinants of weight loss, a 4-week in-patient comprehensive weight reduction program was introduced in which food intake and physical activity were under the strict control. Women (n = 67, BMI: 32.4+/-4.4 kg; age: 48.7+/-12.2 years) who exhibited stable weight on a 7 MJ/day diet during the first week of weight management were given a hypocaloric diet yielding daily energy deficit 2.5 MJ over the subsequent 3-week period. This treatment resulted in a mean weight loss of 3.80+/-1.64 kg. Correlation analysis revealed that baseline concentrations of several hormones were significantly associated either with a higher (free triiodothyronine, C-peptide, growth hormone, pancreatic polypeptide) or with a lower (insulin-like growth factor-I, cortisol, adiponectin, neuropeptide Y) reduction of anthropometric parameters in response to weight management. In a backward stepwise regression model age, initial BMI together with baseline levels of growth hormone, peptide YY, neuropetide Y and C-reactive protein predicted 49.8 % of the variability in weight loss. Psychobehavioral factors (items of the Eating Inventory, Beck Depression score) did not contribute to weight change induced by a well-controlled short-term weight reduction program.