Effect of short-duration physical activity and ventilation threshold on subjective appetite and short-term energy intake in boys

The purpose of this investigation was twofold: (1) to examine the role of low- to moderate-intensity, short-duration physical activity on subjective appetite and (2) to identify the role of and associations between ventilation threshold (VeT) and energy intake at a pizza lunch 30 min after glucose and whey protein drinks in normal weight boys. In 14 boys (age: 12.5+/-0.4 years) subjective appetite was measured before and after a 12 min walking protocol designed to determine physical fitness based on the VeT. On a separate occasion food intake (FI) and subjective appetite were measured in response to sweetened preloads of either a SPLENDA Sucralose control, glucose or whey protein made up to 250 ml with water, given in random order to each boy, 2h after a standardized breakfast. Subjective average appetite and prospective food consumption scores increased after physical activity. VeT was positively associated with FI at a pizza lunch consumed 30 min after glucose and whey protein drinks. Glucose and whey protein reduced FI similarly at lunch compared with control. In conclusion, appetite is increased by low- to moderate-intensity, short-duration physical activity and FI following glucose and protein preloads is positively associated with fitness levels in boys.     

Influence of dietary carbohydrates and glycaemic response on subjective appetite and food intake in healthy elderly persons

Increased satiety and decreased food intake are reported following the consumption of low glycaemic index (GI) foods, which gradually increase blood glucose. This observation, however, is not uniformly supported and few studies have examined the impact of different GI foods on satiety and intake in the elderly. After an overnight fast, 10 men and 10 women (aged 60-82 years) consumed similar amounts of available carbohydrate as high (glucose drink or potatoes) or low (barley) GI foods or a non-energy placebo drink on four mornings. Blood glucose and subjective appetite were measured throughout a 120 min post-ingestion period, followed by consumption of an ad libitum lunch. Differences in plasma glucose after test food ingestion (glucose > potatoes > barley > placebo; P < 0.03) did not predict subjective appetite or lunch intake. Potatoes increased subjective satiety the most, followed by barley, then glucose, which trended towards greater satiety than placebo. Potatoes led to less hunger than placebo (P = 0.0023) and less prospective consumption than the other three foods (P < 0.0083), and potatoes and barley led to greater fullness than glucose and placebo (P < 0.0001). Lunch intake was decreased, compared with placebo (502 +/- 47 kcal, P < 0.031), by potatoes (405 +/- 40 kcal) and barley (441 +/- 41 kcal); however, only potatoes (41.9 +/- 12.3%) led to greater compensation at lunch for test food ingestion compared with glucose (11.9 +/- 9.5%, P = 0.016). These results suggest that elderly subjects are sensitive to the effects of different foods on subjective appetite and food intake, and that the GI of the foods tested did not predict their effects on satiety and food intake.     

Dietary iron intake and availability are related to maternal education level in overweight/obese adolescents

Purpose

To compare intakes of dietary iron and enhancers and inhibitors of iron absorption between overweight/obese (OW/OB) adolescents and their normal weight (NW) peers, and between parental education levels stratified by weight status.

Methods

This was a comparative cross-sectional study of adolescents (n 121 OW/OB and n 102 NW) aged 12–14 years, attending a secondary school in Nonthaburi province, Thailand. Socio-demographic data were obtained from participants’ parents using a questionnaire. Participants recorded their intakes for 3 non-consecutive days, using a prospective food record.

Results

Compared with NW adolescents, OW/OB adolescents consumed more total protein and animal protein after adjustment for energy intake (both p = 0.047). OW/OB adolescents whose mothers were less educated consumed more total iron and available iron after adjustment for energy intake, compared with their OW/OB peers whose mothers were more educated (p = 0.045 and p = 0.040). NW adolescents with more highly educated mothers had higher absolute and energy-adjusted fibre intakes (both p = 0.047). However, NW adolescents of mothers with a high–intermediate level of education consumed less calcium, after adjustment for energy intake (p = 0.028).

Conclusions

OW/OB adolescents with less educated mothers had higher energy-adjusted intakes of iron and available iron. Dietary differences in OW/OB adolescents relative to maternal education, and other socioeconomic indicators, should be explored in a nationally representative data set.

     

The effect of duration of exercise at the ventilation threshold on subjective appetite and short-term food intake in 9 to 14 year old boys and girls

Background  

The effect of exercise on subjective appetite and short-term food intake has received little investigation in children. Despite a lack of reported evaluation of short-duration activity programs, they are currently being implemented in schools as a means to benefit energy balance. The purpose of this study was to determine the effect of duration of exercise at the ventilation threshold (VeT) on subjective appetite and short-term food intake in normal weight boys and girls aged 9 to 14 years.     

Effect of prior exercise on postprandial triglycerides in overweight young women after ingesting a high-carbohydrate meal

To examine the effect of prior exercise on the postprandial lipid response to a high-carbohydrate meal in normal-weight (NW=BMI <25) and overweight (OW=BMI >or= 25) women (age 18-25), 10 NW and 10 OW participants completed 2 conditions separated by 1 month. In the morning, the day after control (CT=no exercise) or exercise conditions (EX=60 min cycling at 60% VO(2peak)), participants consumed a high-carbohydrate meal (80% CHO, 15% protein, 5% fat; 75 kJ/kg BM) followed by 6 hr of hourly blood sampling. Blood was analyzed for triglycerides (TG), blood glucose (BG), and insulin (IN). TG levels over the 6-hr period were lower in NW than OW (p= .021) and lower in EX than in CT (p= .006). Area under the curve (AUC) for TG was lower in NW than OW (p= .016) and EX than CT (p= .003). There were nonsignificant tendencies for reduced BG over time (p= .053) and AUC (p= .083), and IN AUC was lower in EX than in CT (p= .040) for both groups and lower in NW than in OW (p= .039). Prior exercise improved TG levels after a high-carbohydrate meal in both groups, and OW women demonstrated a greater postprandial lipemic response than NW regardless of condition. There were tendencies for improved glucose removal with prior exercise in NW vs. OW. Acute exercise can improve postprandial TG responses and might also improve postprandial BG and IN after a large meal in NW and OW young women.     

Influence of dietary carbohydrates and glycaemic response on subjective appetite and food intake in healthy elderly persons

Increased satiety and decreased food intake are reported following the consumption of low glycaemic index (GI) foods, which gradually increase blood glucose. This observation, however, is not uniformly supported and few studies have examined the impact of different GI foods on satiety and intake in the elderly. After an overnight fast, 10 men and 10 women (aged 60-82 years) consumed similar amounts of available carbohydrate as high (glucose drink or potatoes) or low (barley) GI foods or a non-energy placebo drink on four mornings. Blood glucose and subjective appetite were measured throughout a 120 min post-ingestion period, followed by consumption of an ad libitum lunch. Differences in plasma glucose after test food ingestion (glucose > potatoes > barley > placebo; P < 0.03) did not predict subjective appetite or lunch intake. Potatoes increased subjective satiety the most, followed by barley, then glucose, which trended towards greater satiety than placebo. Potatoes led to less hunger than placebo (P = 0.0023) and less prospective consumption than the other three foods (P < 0.0083), and potatoes and barley led to greater fullness than glucose and placebo (P < 0.0001). Lunch intake was decreased, compared with placebo (502 ± 47 kcal, P < 0.031), by potatoes (405 ± 40 kcal) and barley (441 ± 41 kcal); however, only potatoes (41.9 ± 12.3%) led to greater compensation at lunch for test food ingestion compared with glucose (11.9 ± 9.5%, P = 0.016). These results suggest that elderly subjects are sensitive to the effects of different foods on subjective appetite and food intake, and that the GI of the foods tested did not predict their effects on satiety and food intake.     

Associations between postprandial insulin and blood glucose responses, appetite sensations and energy intake in normal weight and overweight individuals: a meta-analysis of test meal studies

It is unclear whether postprandial blood glucose or insulin exerts a regulatory function in short-term appetite regulation in humans. The aim of this study was to investigate, by use of meta-analysis, the role of blood glucose and insulin in short-term appetite sensation and energy intake (EI) in normal weight and overweight participants. Data from seven test meal studies were used, including 136 healthy participants (ALL) (92 normal weight (NW) and 44 overweight or obese (OW)). All meals were served as breakfasts after an overnight fast, and appetite sensations and blood samples were obtained frequently in the postprandial period. Finally, an ad libitum lunch was served. Data were analysed by fixed effects study level (SL) meta-regression analysis and individual participant data (IPD) regression analysis, using STATA software. In SL analysis, postprandial insulin response was associated with decreased hunger in ALL, NW and OW (P < 0.019), and with increased satiety in NW (P = 0.004) and lower subsequent EI in OW (P = 0.022). Multivariate IPD analysis showed similar associations, but only in NW for hunger, satiety and EI (P < 0.028), and in ALL for EI (P = 0.016). The only association involving blood glucose was the multivariate IPD analysis showing an inverse association between blood glucose and EI in ALL (P = 0.032). Our results suggest that insulin, but not glucose, is associated with short-term appetite regulation in healthy participants, but the relationship is disrupted in the overweight and obese. We conclude that the postprandial insulin response may be an important satiety signal, and that central nervous system insulin resistance in overweight might explain the blunted effect on appetite.     

Insoluble cereal fiber reduces appetite and short-term food intake and glycemic response to food consumed 75 min later by healthy men

BACKGROUND: Insoluble fiber consumption is associated with reduced risk of obesity and diabetes, but its mechanisms of action are unknown. OBJECTIVE: The objective was to describe the effect of insoluble fiber on appetite, short-term food intake, and blood glucose (BG) before and after a meal 75 min later in healthy men. DESIGN: In a crossover design, high-fiber (HF; 33 g insoluble fiber) cereal, low-fiber (LF) cereal, white bread (WB), and water control were administered to young men after an overnight fast. Caloric treatments had similar energy, macronutrient content, volume, and weight. In the first experiment, subjective appetite and BG were measured at 15-min intervals before and after an ad libitum meal at 75 min. In the second experiment, a preset pizza meal (850 kcal) was consumed at 75 min. Appetite and blood glucose were measured for 150 min at fasting and at 15-min intervals before and after the fixed meal. RESULTS: In experiment 1, ad libitum food intake was lower after the HF cereal and WB than after the LF cereal and water (937 +/- 86, 970 +/- 65, 1109 +/- 90, 1224 +/- 89 kcal, respectively; P < 0.001). Appetite was lower (P < 0.05) after the HF cereal than after the WB but not different from the LF cereal. The BG area under the curve (AUC) did not differ among the HF cereal, WB, and LF cereal from 0 to 75 min, but the postmeal BG increased after the WB and LF cereal but not after the HF cereal. In experiment 2, the HF cereal, but not the LF cereal or WB, increased fullness before and prevented an increase in the BG AUC after the preset meal (P < 0.05). CONCLUSION: A serving of 33 g insoluble fiber reduced appetite, lowered food intake, and reduced glycemic response to a meal consumed 75 min later.     

The effect of yellow pea protein and fibre on short-term food intake, subjective appetite and glycaemic response in healthy young men

Pulses are low-glycaemic foods rich in protein (20-25?%), resistant starch and fibre that suppress appetite and glycaemia. The objective of the present study was to elucidate the component(s) of yellow peas responsible for these benefits and assess their efficacy as value-added food ingredients. We investigated the effects of 10 or 20?g of isolated yellow pea protein (P10 and P20) or fibre (F10 and F20) on food intake (FI) at an ad libitum pizza meal served at 30?min (Expt 1, n 19) or 120?min (Expt 2, n 20) and blood glucose (BG) and appetite in young, healthy males (20-30 years). In Expt 1, P20 led to lower FI than control (4937 (sem 502) v. 5632 (sem 464)?kJ (1180 (sem 120) v. 1346 (sem 111)?kcal)) and all other treatments (P?相似文献   

Gender effect on exercise-induced energy intake modification among obese adolescents

This study examined gender differences in terms of energy intake and appetite feelings after an acute bout of physical exercise among obese adolescents. Seven obese girls and seven obese boys were asked to complete a sedentary and an exercise session in random order, where their food consumption and appetite sensations were assessed. Both boys and girls showed a significant reduction of energy intake on the exercise day without any modification of their appetite readings and no gender differences in food consumption and appetite responses to an acute exercise were noted.     

Effects of glucose-to-fructose ratios in solutions on subjective satiety, food intake, and satiety hormones in young men

BACKGROUND: The greater prevalence of obesity and the metabolic syndrome in the past 35 y has been attributed to the replacement of sucrose in the food supply with high-fructose corn syrup (HFCS). OBJECTIVE: Two experiments were conducted to determine the effect of solutions containing sucrose, HFCS, or various ratios of glucose to fructose (G:F) on food intake (FI), average appetite (AA), blood glucose (BG), plasma insulin, ghrelin, and uric acid (UA) in men. DESIGN: Sugar solutions (300 kcal/300 mL) were (in %) G20:F80, HFCS 55 (G45:F55), sucrose, and G80:F20 (experiment 1, n = 12) and G20:F80, G35:F65, G50:F50, sucrose, and G80:F20 (experiment 2, n = 19). The controls were a sweet energy-free control (experiment 1) and water (both experiments). Solutions were provided in a repeated-measures design. AA, BG, and FI were measured in all subjects. Hormonal responses and UA were measured in 7 subjects in experiment 2. Measurements were taken from baseline to 75 min. FI was measured at 80 min. RESULTS: Sucrose and HFCS (experiment 1) and sucrose and G50:F50 (experiment 2) had similar effects on all dependent measures. All sugar solutions similarly reduced the AA area under the curve (AUC). FI and plasma UA concentrations were significantly (P < 0.05) lower after high-glucose solutions than after low-glucose solutions. The lower FI was associated with a greater BG AUC (P < 0.05) and smaller AA and ghrelin AUCs (P < 0.01). Insulin and BG AUCs were positively associated (P < 0.001). CONCLUSION: Sucrose, HFCS, and G50:F50 solutions do not differ significantly in their short-term effects on subjective and physiologic measures of satiety, UA, and FI at a subsequent meal.     

Acute effects of dietary fibre and glycaemic carbohydrate on appetite and food intake in healthy males

The aim of this research was to describe the effect of equal weights of insoluble fibre (wheat bran) and glycaemic carbohydrate (glucose) on appetite and food intake over 1 and 2h in healthy men. In a crossover design, high-fibre (F; 41 g insoluble fibre) cereal, low-fibre (W; 1g fibre) cereal, F plus glucose (FG; 41 g glucose), and W plus glucose (WG; 41 g glucose) were administered to young men after an overnight fast. Treatments had similar fat, protein, volume and weight. In the first experiment, subjective appetite was measured at 15 min intervals before an ad libitum meal at 60 min. In the second experiment, subjective appetite was measured at 15 min intervals for the first 60 and 30 min intervals for the second 60 min before an ad libitum meal at 120 min. In experiment 1, ad libitum food intake was lower after the F, WG and FG cereals compared to W (3.1, 2.98, 2.96 and 3.59 MJ, respectively). Total energy intake (cereal+ad libitum) was lower after F compared to W and WG (4.1, 4.6, and 4.7 MJ, respectively). In experiment 2, the WG cereal significantly reduced ad libitum food intake compared to W (3.90 and 4.57 MJ, respectively). These results suggest that a serving of 41 g insoluble fibre reduces food intake independent of its weight and volume and similar to an equal weight of glucose within 60 min, but this effect is not maintained after 120 min.     

The Beneficial Effect of Cinnamon and Red Capsicum Intake on Postprandial Changes in Plasma Metabolites Evoked by a High-Carbohydrate Meal in Men with Overweight/Obesity

The relationship of high-carbohydrate (HC) meal intake to metabolic syndrome is still not fully explained. Metabolomics has the potential to indicate metabolic pathways altered by HC meals, which may improve our knowledge regarding the mechanisms by which HC meals may contribute to metabolic syndrome development. The fasting and postprandial metabolic response to HC or normo-carbohydrate (NC) meals with/without cinnamon + capsicum intake was evaluated using untargeted metabolomics and compared between normal-weight (NW) and overweight/obese (OW/OB) healthy men. Healthy male participants (age-matched) were divided into two groups (12 subjects per group). One was composed of men with normal weight (NW) and the other of men with overweight/obesity (OW/OB). On separate visits (with 2–3 week intervals), the participants received standardized HC or NC meals (89% or 45% carbohydrates, respectively). Fasting (0 min) and postprandial (30, 60, 120, 180 min) blood were collected for untargeted plasma metabolomics. Based on each metabolic feature’s intensity change in time, the area under the curve (AUC) was calculated. Obtained AUCs were analyzed using multivariate statistics. Several metabolic pathways were found dysregulated after an HC meal in people from the OW/OB group but not the NW group. The consumption of HC meals by people with overweight/obesity led to a substantial increase in AUC, mainly for metabolites belonging to phospholipids and fatty acid amides. The opposite was observed for selected sphingolipids. The intake of cinnamon and capsicum normalized the concentration of selected altered metabolites induced by the intake of HC meals. A HC meal may induce an unfavourable postprandial metabolic response in individuals with overweight/obesity, and such persons should avoid HC meals.     

First and second meal effects of pulses on blood glucose, appetite, and food intake at a later meal

Pulses are low-glycemic appetite-suppressing foods, but it is not known whether these properties persist after being consumed as part of a meal and after a second meal. The objective of this study was to determine the effects of a fixed-size pulse meal on appetite and blood glucose (BG) before and after an ad libitum test meal (pizza) and on food intake (FI) at the test meal. Males (n = 25; 21.3 ± 0.5 years; 21.6 ± 0.3 kg·m(-2)) randomly consumed 4 isocaloric meals: chickpea; lentil; yellow split pea; and macaroni and cheese (control). Commercially available canned pulses provided 250 kcal, and were consumed with macaroni and tomato sauce. FI was measured at a pizza meal 260 min after consumption of the isocaloric meal. BG and appetite were measured from 0 to 340 min. The lentil and yellow pea, but not chickpea, treatments led to lower appetite ratings during the 260 min prepizza meal period, and less FI at the pizza meal, compared with macaroni and cheese (p < 0.05). All pulse treatments lowered BG immediately following consumption (at 20 min) (p < 0.05), but there was no effect of treatment on prepizza meal BG AUC (p = 0.07). Immediately after the pizza meal, BG was lower following the chickpea and lentil treatments, but not the yellow pea treatment (p < 0.05). Postpizza meal BG AUC was lower following the chickpea and lentil treatments than in the yellow pea treatment (p < 0.05). The beneficial effects of consuming a pulse meal on appetite, FI at a later meal, and the BG response to a later meal are dependent on pulse type.     

Deleterious effects of omitting breakfast on insulin sensitivity and fasting lipid profiles in healthy lean women

BACKGROUND: Breakfast consumption is recommended, despite inconclusive evidence of health benefits. OBJECTIVE: The study's aim was to ascertain whether eating breakfast (EB) or omitting breakfast (OB) affects energy intake, energy expenditure, and circulating insulin, glucose, and lipid concentrations in healthy women. DESIGN: In a randomized crossover trial, 10 women [x+/-SD body mass index (BMI; in kg/m2): 23.2+/-1.4] underwent two 14-d EB or OB interventions separated by a 2-wk interval. In the EB period, subjects consumed breakfast cereal with 2%-fat milk before 0800 and a chocolate-covered cookie between 1030 and 1100. In the OB period, subjects consumed the cookie between 1030 and 1100 and the cereal and milk between 1200 and 1330. Subjects then consumed 4 additional meals with content similar to usual at predetermined times later in the day and recorded food intake on 3 d during each period. Fasting and posttest meal glucose, lipid, and insulin concentrations and resting energy expenditure were measured before and after each period. RESULTS: Reported energy intake was significantly lower in the EB period (P=0.001), and resting energy expenditure did not differ significantly between the 2 periods. OB was associated with significantly higher fasting total and LDL cholesterol than was EB (3.14 and 3.43 mmol/L and 1.55 and 1.82 mmol/L, respectively; P=0.001). The area under the curve of insulin response to the test meal was significantly lower after EB than after OB (P<0.01). CONCLUSION: OB impairs fasting lipids and postprandial insulin sensitivity and could lead to weight gain if the observed higher energy intake was sustained.     

Aspartame: effect on lunch-time food intake, appetite and hedonic response in children

Two experiments were conducted, each with 20 healthy 9-10-year-old children. After an overnight fast, subjects were given a standardized breakfast at 0830 hrs, the treatments at 1030 hrs, and a lunch containing an excess of foods at 1200 hrs. Visual analog scales of hunger, fullness, and desire to eat were administered 5 min before and 20 and 85 min after treatment. Lunch-time food intake was measured. In experiment 1, either aspartame (34 mg/kg), or the equivalent sweetness of sodium cyclamate, was given in an ice slurry (300 ml) of unsweetened strawberry Kool-Aid with carbohydrate (1.75 g/kg polycose). In experiment 2, drinks (300 ml) contained either sucrose (1.75 g/kg) or aspartame (9.7 mg/kg). In both experiments, significant meal- and time-dependent effects were observed for subjective feelings of hunger, fullness and desire to eat. Treatments, however, did not affect either subjective feelings of appetite or lunch-time food intake. Thus, aspartame consumed without or with carbohydrate, did not affect either hunger or food intake of children when compared with the sweeteners sodium cyclamate and sucrose, respectively.     

Energy intake and appetite are related to antral area in healthy young and older subjects

BACKGROUND: Gastric distension reduces food intake, and antral, rather than proximal, gastric distension may be the dominant mechanism in the induction of appetite-related sensations. Healthy aging is associated with reduced appetite. OBJECTIVE: We examined the effects of different energy preloads on appetite, plasma cholecystokinin, antral area, and subsequent energy intake in healthy older and young subjects. DESIGN: On 3 separate days, 12 young and 12 older subjects consumed 400 mL of a drink containing either 0 kcal (water), 250 kcal, or 750 kcal 70 min before a buffet-style meal. RESULTS: Hunger was less in the older than in the young subjects (P < 0.001). Both nutrient preloads reduced hunger and increased fullness more than did water (P < 0.02), and older subjects were more full than were the young (P < 0.05). Antral area was greater after the nutrient preloads than after water (P = 0.001) and greater in the older than in the young subjects (P = 0.005). In both groups, food intake was suppressed in an energy-dependent manner (P = 0.008). Plasma cholecystokinin was greater in the older than in the young subjects (P = 0.003). Immediately before the meal, hunger (r = -0.59) and energy intake (r = -0.90) were inversely related and fullness (r = 0.66) was directly related to antral area (all: P < 0.001). Antral area, but not plasma cholecystokinin, was a predictor of subsequent energy intake. CONCLUSION: In healthy young and older subjects, the suppression of subsequent energy intake by a liquid preload is nutrient dependent and comparable, and both satiation and satiety are related to antral area and (presumably) antral distension.     

The ability of habitual exercise to influence appetite and food intake in response to high- and low-energy preloads in man

The present study tested the hypothesis that habitual exercisers demonstrate an increased accuracy of regulation of food intake in compensation for previous dietary energy intake. Twenty-three lean healthy male subjects were divided into two groups on the basis of their habitual exercise levels: non-exercisers (no exercise sessions/week, n 9), and exercisers (>two exercise sessions of 40 min or more/week, n 14). The appetite response to covert liquid preloads of high (2513 kJ) energy (HE) and low (1008 kJ) energy (LE) was investigated Sixty minutes after the preload subjects were offered an ab libitum buffet-style meal and energy intake (EI) was calculated. Subjective hunger and satiety were assessed throughout using self-rated visual-analogue scales. Buffet EI in non-exercisers was not significantly different following the LE or HE preloads (mean compensation 7 %), but the exercise group significantly reduced their energy intake following the HE, compared with the LE, preload (mean compensation 90 %; P=0.0035). A broadly similar pattern of response was observed for both moderate (two to three sessions/week, n 7) and high exercisers (>four sessions/week, n 7). There were no significant differences between hunger or satiety ratings following HE or LE preloads for either group. However non-exercisers scored significantly higher on their self-ratings of hunger at the start of the study, before preload consumption, compared with the exercisers (P<0.01). These findings demonstrate that habitual exercisers have an increased accuracy of short-term regulation of food intake in compensation for preload manipulation, and provide additional support for advocating regular exercise in the prevention of overweight and obesity.     

Inverse association between the effect of carbohydrates on blood glucose and subsequent short-term food intake in young men

BACKGROUND: A primary mechanism by which carbohydrates are thought to regulate satiety and food intake is through their effect on blood glucose. OBJECTIVES: The objectives were to describe the effect of defined carbohydrate preloads on food intake and blood glucose and to determine the association between food intake and blood glucose. DESIGN: Three experiments were conducted in which selected carbohydrates as 1255-kJ isovolumetric beverages were administered to young men after an overnight fast. Measurements of blood glucose and appetite were made at specified times during the next 60 min. Food intake was measured at 60 min. RESULTS: Glucose resulted in the highest glycemic response, which was followed, in order, by the responses to polycose, sucrose, amylopectin, a fructose-glucose mixture, and amylose. The high-glycemic-index preloads (glucose, polycose, and sucrose) resulted in lower mealtime energy intake during a test meal at 1 h, but the low-glycemic-index preloads (amylose, amylopectin, and a fructose-glucose mixture) did not. An inverse relation was observed between the blood glucose concentrations in the area under the curve and the subjective appetite (r = -0.23, P < 0.05) and food intake at 60 min (r = -0.24, P < 0.05). CONCLUSIONS: Food intake and subjective appetite are inversely associated with blood glucose response in the 60 min after consumption of carbohydrates. Carbohydrates with a high glycemic index (glucose, polycose, and sucrose) suppress subjective appetite and food intake in the short term, but those with a low glycemic index (amylose and amylopectin) do not.     

Body composition and cardiovascular risk factors in pretransplant hemodialysis patients

BACKGROUND: Obesity, hyperlipemia and cardiovascular complications contribute to a significant proportion of morbidity and mortality of renal transplant patients and have negative effects on renal survival. Aim of the present study was to evaluate the main abnormalities in body composition and the prevalence of some cardiovascular risk factors in a population of hemodialyzed (HD) patients awaiting renal transplantation. METHODS: We studied 151 HD patients, all included in a waiting list for renal transplantation, 97 males and 54 females, with mean age 47.4+/-12 years. Patients were divided into three groups according to their body mass index (BMI) (kg/m2): 18.5 to 24.9 (normoweight, NW); 25.0 to 29.9 (overweight, OW); > or =30 (obese, OB). The body composition measurements were obtained the day after the mid-week HD session using bioelectrical impedance analysis (BIA). RESULTS: We found that 47 patients were NW (31%), while 56 were OW (37%), and 48 were OB (32%). BIA-measured body cell mass was (BCM) significantly increased in the OW as compared with the NW group (P<0.001), but, of note, no significant difference was found in OB group in comparison with the OW. Total cholesterol and triglycerides plasma levels were significantly elevated in OW and OB patients with respect to NW (P<0.05) and an increased prevalence of diabetes was seen in OB patients (NW: 6%, OW: 5%, OB: 12%). CONCLUSIONS: These data show that a large proportion of patients awaiting renal transplant are overweight or obese and a consistent part of them have other cardiovascular risk factors associated. Furthermore, obese HD patients have a BCM lower than predicted on the basis of BMI and show an altered metabolic profile. A better understanding of the characteristics of patients included in the renal transplant waiting list is crucial in order to design prospective studies that aim to define the proper risk profile for the selection of patients.