Impact of a non-restrictive satiating diet on anthropometrics, satiety responsiveness and eating behaviour traits in obese men displaying a high or a low satiety phenotype.

The aim of this study was to evaluate the impact of a non-restrictive satiating diet in men displaying various degrees of satiety efficiency. In all, sixty-nine obese men aged 41·5 (sd 5·7) years were randomly assigned to a control (10-15, 55-60 and 30 % energy as protein, carbohydrate and lipid, respectively; n 34) or satiating (20-25, 45-50 and 30-35 % energy as protein, carbohydrate and lipid, respectively; n 35) diet for 16 weeks, and were classified as having a low (LSP) or high (HSP) satiety phenotype. Both diets were consumed ad libitum. Changes in body weight, BMI, percent fat mass, waist circumference, satiety responsiveness and eating behaviour traits were assessed following the intervention. Dropout rates were higher in the control diet (44·1 %) compared with the satiating diet (8·6 %). Decreases in body weight, BMI and waist circumference were significant in both groups, yet HSP individuals lost more body weight than LSP individuals (P=0·048). Decreases in % fat mass were greater in the satiating diet (LSP: -2·1 (sd 2·1) %; P<0·01 and HSP: -3·0 (sd 2·5) %; P<0·001) compared with the control diet (LSP: -1·1 (sd 2·5) % and HSP: -1·3 (sd 2·6) %) (P=0·034). Satiety responsiveness was markedly improved in the satiating diet, whereas no significant changes were observed in the control group. Changes in dietary restraint (+3·3 (sd 2·9) to +7·2 (sd 5·5)), flexible control (+0·9 (sd 1·4) to +2·3 (sd 2·7)), rigid control (+2·2 (sd 1·5) to +2·5 (sd 2·8)), disinhibition (-2·8 (sd 3·7) to -3·2 (sd 2·6)) and susceptibility to hunger (-2·7 (sd 4·1) to -4·6 (sd 3·9)) were similar between the diets. Compared with the control diet, the satiating diet favoured adherence, decreased % fat mass and improved satiety responsiveness in both HSP and LSP individuals.

Fitness, adiposopathy, and adiposity are independent predictors of insulin sensitivity in middle-aged men without diabetes

Adiposopathy, or sick fat, refers to adipose tissue dysfunction that can lead to several complications such as dyslipidemia, insulin resistance, and hyperglycemia. The relative contribution of adiposopathy in predicting insulin resistance remains unclear. We investigated the relationship between adiposopathy, as assessed as a low plasma adiponectin/leptin ratio, with anthropometry, body composition (hydrostatic weighing), insulin sensitivity (hyperinsulinemic-euglycemic clamp), inflammation, and fitness level (ergocycle VO2max, mL/kgFFM/min) in 53 men (aged 34-53 years) from four groups: sedentary controls without obesity (body mass index [BMI] <25 kg/m2), sedentary with obesity (BMI > 30 kg/m2), sedentary with obesity and glucose intolerance, and endurance trained active without obesity. The adiponectin/leptin ratio was the highest in trained men (4.75 ± 0.82) and the lowest in glucose intolerant subjects with obesity (0.27 ± 0.06; ANOVA p < 0.0001) indicating increased adiposopathy in those with obesity. The ratio was negatively associated with adiposity (e.g., waist circumference, r = −0.59, p < 0.01) and positively associated with VO2max (r = 0.67, p < 0.01) and insulin sensitivity (M/I, r = 0.73, p < 0.01). Multiple regression analysis revealed fitness as the strongest independent predictor of insulin sensitivity (partial R2 = 0.61). While adiposopathy was also an independent and significant contributor (partial R2 = 0.10), waist circumference added little power to the model (partial R2 = 0.024). All three variables remained significant independent predictors when trained subjects were excluded from the model. Plasma lipids were not retained in the model. We conclude that low fitness, adiposopathy, as well as adiposity (and in particular abdominal obesity) are independent contributors to insulin resistance in men without diabetes (AU)

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Fitness, adiposopathy, and adiposity are independent predictors of insulin sensitivity in middle-aged men without diabetes.

Adiposopathy, or sick fat, refers to adipose tissue dysfunction that can lead to several complications such as dyslipidemia, insulin resistance, and hyperglycemia. The relative contribution of adiposopathy in predicting insulin resistance remains unclear. We investigated the relationship between adiposopathy, as assessed as a low plasma adiponectin/leptin ratio, with anthropometry, body composition (hydrostatic weighing), insulin sensitivity (hyperinsulinemic-euglycemic clamp), inflammation, and fitness level (ergocycle VO2max, mL/kgFFM/min) in 53 men (aged 34-53 years) from four groups: sedentary controls without obesity (body mass index [BMI] <25 kg/m(2)), sedentary with obesity (BMI > 30 kg/m(2)), sedentary with obesity and glucose intolerance, and endurance trained active without obesity. The adiponectin/leptin ratio was the highest in trained men (4.75 ± 0.82) and the lowest in glucose intolerant subjects with obesity (0.27 ± 0.06; ANOVA p < 0.0001) indicating increased adiposopathy in those with obesity. The ratio was negatively associated with adiposity (e.g., waist circumference, r = -0.59, p < 0.01) and positively associated with VO2max (r = 0.67, p < 0.01) and insulin sensitivity (M/I, r = 0.73, p < 0.01). Multiple regression analysis revealed fitness as the strongest independent predictor of insulin sensitivity (partial R (2) = 0.61). While adiposopathy was also an independent and significant contributor (partial R (2) = 0.10), waist circumference added little power to the model (partial R (2) = 0.024). All three variables remained significant independent predictors when trained subjects were excluded from the model. Plasma lipids were not retained in the model. We conclude that low fitness, adiposopathy, as well as adiposity (and in particular abdominal obesity) are independent contributors to insulin resistance in men without diabetes.

Short- and long-term effects of continuous versus intermittent restrictive diet approaches on body composition and the metabolic profile in overweight and obese postmenopausal women: a pilot study.

OBJECTIVE: The objective of this study was to compare changes in body composition and the metabolic profile between women taking an intermittent diet (ID) and women taking a continuous diet (CD). METHODS: Twenty-five obese postmenopausal women were randomized to an ID (n = 13) or a CD (n = 12). In the ID, 5-week energy restriction periods were followed by 5-week weight stabilization periods. In the CD, 15 weeks of energy restriction was followed by 5 weeks of weight stabilization. Outcome measures before, during, and after weight loss, as well as after a 1-year follow-up, were body weight and composition, waist circumference, resting metabolic rate, and fasting lipid and glucose levels. RESULTS: Body weight, waist circumference, percentage fat mass, and fat mass decreased significantly and similarly in both groups (P < 0.0001). Both groups showed similar overall decreases in plasma total cholesterol and triglycerides (all P < 0.05). Low-density lipoprotein cholesterol improved significantly in the CD group only, whereas fasting glucose decreased significantly in the ID group only. High-density lipoprotein cholesterol and resting metabolic rate remained stable in both groups. Fasting plasma triglyceride and glucose levels were the only metabolic variables to further improve after the fifth week of the protocol. At the 1-year follow-up, both interventions were associated with successful and similar weight loss maintenance and improvements in fasting plasma glucose levels. CONCLUSIONS: The ID resulted in similar short- and long-term changes in body composition and metabolic profile compared with a CD. Most improvements occurred during the first 5 weeks of treatment in both interventions.

Effects of rapid or slow weight loss on body composition and metabolic risk factors in obese postmenopausal women. A pilot study.

To compare the effect of rapid or slow weight loss (WL) on body composition and metabolic risk factors following a caloric restriction. Ten obese, postmenopausal women were matched for total body WL. Dependent variables were: body composition, lipid profile and blood pressure. Both groups decreased obesity measures (all P≤0.05) while lean body mass decreased in the rapid WL group (P≤0.05). Significant improvements in fasting triglyceride level and diastolic blood pressure were observed only in the slow WL group. A slower WL seems to be more beneficial to improve body composition as well as metabolic risk factors in postmenopausal women.

Functional food and satiety. Impact of a satiating context effect on appetite control of non-obese men.

The aim of this study was to verify if the addition of satiating nutrients and a satiating context effect could influence appetite sensations, spontaneous energy intake and food appreciation under conditions of standardized energy density of a meal. Eighteen non-obese men were submitted to a control, a satiating, and a context effect condition composed of a standardized breakfast and an ad libitum test lunch (macaroni entrée plus chocolate cake). The satiating macaroni contained more proteins, unsaturated fats, fibres and calcium than the control macaroni despite similar energy density, appearance and palatability. In the context effect condition, participants believed they were eating "a highly satiating macaroni", but were served the control macaroni. Appreciation of the macaronis, quantities of macaroni and cake consumed and 4-h satiating potential were measured for each condition. Quantities of macaroni and dessert consumed did not differ between conditions. Satiating potential was greater for the context effect meal compared to the control and/or the satiating meals up to 4h after its consumption. The context effect macaroni obtained higher appreciation rates than the control and the satiating macaronis. The context effect may positively influence the appreciation toward a meal and contribute to increase its satiety potential for many hours.

Healthy eating at school to compensate for the activity-related obesigenic lifestyle in children and adolescents: the Quebec experience.

In this article, we describe the Quebec experience about the determinants of childhood obesity and the search for solutions, which are well adapted to the constraints of the current lifestyle. As expected, it is likely that a decrease in physical fitness and its related sedentariness as well as suboptimal food habits have contributed to the increase in overweight prevalence that was observed between 1980 and 2000. Our research experience suggests that other less suspected activity related factors have also played an important role in the occurrence of the obesity epidemic. This is particularly the case for short sleeping and demanding mental work, which are features of our modern lifestyle. Because there is no foreseeable prospect for a change in sleep and mental work habits, we argue that compensations in other factors may be necessary to prevent weight gain in this new context. We thus developed a concept of food design aiming at the maximization of the satiating properties of a food or a meal course. In this context, we were successful in the design of healthy lunch bags for students of a school located in a low socioeconomic area. Indeed, for a majority of menus, an optimal compromise seemed to be reached between nutrient composition, satiating potential, palatability, and financial accessibility. In summary, the Quebec experience reveals that childhood obesity is a complex problem that partly results from unsuspected environmental factors that deserve creative solutions to at least partly compensate for their effect.

Impact of adopting a vegan diet or an olestra supplementation on plasma organochlorine concentrations: results from two pilot studies.

The aim of these studies was to evaluate the potential of some nutritional approaches to prevent or reduce the body load of organochlorines (OC) in humans. Study 1 compared plasma OC concentrations between vegans and omnivores while study 2 verified if the dietary fat substitute olestra could prevent the increase in OC concentrations that is generally observed in response to a weight-reducing programme. In study 1, nine vegans and fifteen omnivores were recruited and the concentrations of twenty-six OC (beta-hexachlorocyclohexane (beta-HCH), p, p'-dichlorodiphenyldichloroethane (p, p'-DDE), p, p'-dichlorodiphenyltrichloroethane (p, p'-DDT), hexachlorobenzene, mirex, aldrin, alpha-chlordane, gamma-chlordane, oxychlordane, cis-nonachlor, trans-nonachlor, polychlorinated biphenyl (PCB) nos. 28, 52, 99, 101, 105, 118, 128, 138, 153, 156, 170, 180, 183 and 187, and aroclor 1260) were determined. In study 2, the concentrations of these twenty-six OC were measured before and after weight loss over 3 months in thirty-seven obese men assigned to one of the following treatments: standard group (33 % fat diet; n 13), fat-reduced group (25 % fat diet; n 14) or fat-substituted group (1/3 of dietary lipids substituted by olestra; n 10). In study 1, plasma concentrations of five OC compounds (aroclor 1260 and PCB 99, PCB 138, PCB 153 and PCB 180) were significantly lower in vegans compared with omnivores. In study 2, beta-HCH was the only OC which decreased in the fat-substituted group while increasing in the other two groups (P = 0.045). In conclusion, there was a trend toward lesser contamination in vegans than in omnivores, and olestra had a favourable influence on beta-HCH but did not prevent plasma hyperconcentration of the other OC during ongoing weight loss.

Interindividual variations in resting metabolic rate during weight loss in obese postmenopausal women A pilot study.

The objective of the study was to examine if decreases in resting metabolic rate (RMR) take place early in the weight loss process and if they remain throughout the duration of the weight loss intervention. Twenty obese postmenopausal women (61.8 +/- 5.9 years) participated in a 15-week weight loss program. After the fifth week, subjects were characterized as having an increased (>5%) or a decreased (<5%) RMR based on baseline values. Afterward, they were followed for an additional 10 weeks. Outcome measures were as follows: fat mass ([FM] total, trunk), lean body mass (total, trunk), RMR, resting heart rate (RHR), and physical activity level. After 5 weeks, significant decreases were observed for lean body mass, FM, and RHR (P < .05), whereas no overall changes in physical activity level and RMR were observed. However, on an individual basis, large variations in RMR were observed (ranging from -320 to +330 kcal/d). Analyses showed that subjects characterized as either having an increased or a decreased RMR after the fifth week maintained these adaptations at the end of intervention. Finally, subjects displaying a decreased RMR during weight loss had a significantly higher RMR and lower FM accumulations at baseline (total and trunk) compared with those with an increased RMR. Interindividual variations in RMR took place early in the weight loss process and were maintained over the duration of the weight loss program in our cohort of obese postmenopausal women. Baseline RMR, changes in RHR, and FM accumulations (total and trunk) seem to be important factors to consider when studying the effects of weight loss on RMR.

Increase in depression symptoms with weight loss: association with glucose homeostasis and thyroid function.

The purpose of this study was to assess the potential impact of weight loss up to a state of plateau on symptoms of depression. Eleven obese men (mean body mass index (BMI)=33.4 kg.m(-2), mean age=38 y) participated in this repeated-measures, within-subjects, clinical intervention. They were subjected to a weight-loss program that consisted of a supervised diet and exercise clinical intervention. The phases investigated were (i) baseline; (ii) after 5+/-1 kg loss of body mass (phase 1); (iii) after 10+/-1 kg weight loss (phase 2); and (iv) at resistance to further weight loss (plateau). At each phase of the weight-reducing program, glucose homeostasis markers were determined using an oral glucose tolerance test (OGTT). Serum thyroid-stimulating hormone (TSH), total triiodothyronine (T3), and free thyroxine (fT4) concentrations were also measured and the Beck Depression Inventory (BDI) was administered. The weight loss plateau occurred after 7.4+/-1.9 months of intervention and corresponded to a loss of 11.2% of initial body weight (93.9% of which was from fat stores). This amount of weight loss induced a significant decrease in resting metabolic rate (RMR) (p<0.05) and a significant increase in desire to eat (p<0.05) and in depression symptoms (p<0.01) compared with baseline. Intriguingly, the glucose area below fasting values (GABF) at plateau was significantly higher as compared with other phases of the program (p<0.01). We found a strong negative correlation (r=-0.77, p<0.01) between the change in glucose concentrations at 180 min of the OGTT and the change in BDI scores between plateau and baseline values. Similarly, highly significant relationships were found between the change in T3 or fT4 concentrations and the change in BDI scores (r=-0.71 and r=-0.68, respectively; p<0.01). Weight loss until plateauing is associated with a trend toward hypoglycemia at the end of the oral glucose challenge and with a decrease in T3 and fT4 levels. These physiological changes are shown to be highly linked with the increase in depression symptoms observed at plateau. Taken together, these data emphasize the relevance of caution and reasonable objectives when prescribing a weight reduction program to obese individuals.

Correlation between the rate of weight loss and changes in body composition in obese postmenopausal women after 5 weeks: a pilot study.

Approximately 25% of weight lost during restrictive diets (without exercise) is lean body mass (LBM). No study has yet investigated the impact of the rate of weight loss (RWL) on LBM and fat mass (FM). The purpose of this study was to investigate the relationships between the RWL and body composition in older obese women. Twenty obese postmenopausal women aged between 51 and 74 years enrolled in a 5 week dietary weight loss intervention. Subjects were characterized according to their RWL (low RWL < 0.74 kg.week(-1) (n = 9) vs. high RWL > or = 0.74 kg.week(-1) (n = 11)). Total and trunk FM and LBM (by dual-energy X-ray absorptiometry) were measured before and after weight loss. A significant correlation was observed between the RWL (kg.week(-1)) and changes in LBM (kg.week(-1)) (r = 0.75; p = 0.0002). However, no association was observed with changes in FM (kg.week(-1)) (r = 0.40; p = 0.08). Both groups showed a similar decrease in FM (low RWL, -2.7 +/- 0.9 kg,; high RWL, -3.2 +/- 0.8 kg; p = 0.38), whereas losses in LBM were significantly higher in the high RWL than in the low RWL group (-1.6 +/- 1.2 kg vs. -0.4 +/- 1.1 kg; p = 0.05). An RWL > 0.74 kg.week(-1) was associated with a greater loss of LBM, but had no extra benefits on FM after a 5 week weight loss program. Current guidelines, which recommend RWL up to 0.91 kg.week(-1), might not be optimal to prevent decreases in LBM in postmenopausal women when no exercise is added.