Subjective Feelings Of Hunger Research Articles

Consequences of chronodisruption on body weight regulation and metabolism

The prevalence of overweight and obesity has increased dramatically. At the same time, lack of sleep has become a part of the modern lifestyle, as well as shift and night work. As a result, chronodisruption, i. e. a change in physiological processes that are controlled by the internal clock, becomes commonplace. Epidemiological data show that too short but also too long sleep are associated with an increased risk of obesity, also seen for night shift work. Overweight and obesity are associated with metabolic syndrome and data likewise report an increased risk by both short and long sleep. It has not yet been conclusively clarified how chronodisruption influences the metabolic risks. Clinical experimental studies report on neuroendocrine and circadian mechanisms and it has been shown that lack of sleep increases the hunger-promoting hormone ghrelin as well as subjective feelings of hunger and increases leptin levels. Lack of sleep also increases hedonic hunger and food-related reward signals. Through preventive measures, chronodisruption and thus, the risk of obesity can be counteracted. The extent to which smartwatches and fitness trackers, which according to the manufacturer can measure and analyze sleep, provide an objective picture of sleep has not been sufficiently investigated. However, smartwatches and fitness trackers can - probably - increase awareness of sleep in the modern society.

Relationship between Ketones, Ghrelin, and, Appetite on Isocaloric Diets with Varying Carbohydrate Quality and Amount: Results from a Randomized Controlled Trial in People with Obesity (CARBFUNC)

BackgroundLow-carbohydrate high-fat (LCHF) diets may suppress the increase in appetite otherwise seen after diet-induced fat loss. However, studies of diets without severe energy restriction are lacking, and the effects of carbohydrate quality relative to quantity have not been directly compared. ObjectivesTo evaluated short- (3 mo) and long-term (12 mo) changes in fasting plasma concentrations of total ghrelin, β-hydroxybutyrate (βHB), and subjective feelings of appetite on 3 isocaloric eating patterns within a moderate caloric range (2000–2500 kcal/d) and with varying carbohydrate quality or quantity. MethodsWe performed a randomized controlled trial of 193 adults with obesity, comparing eating patterns based on “acellular” carbohydrate sources (e.g., flour-based whole-grain products; comparator arm), “cellular” carbohydrate sources (minimally processed foods with intact cellular structures), or LCHF principles. Outcomes were compared by an intention-to-treat analysis using constrained linear mixed modeling. This trial was registered at clinicaltrials.gov as NCT03401970. ResultsOf the 193 adults, 118 (61%) and 57 (30%) completed 3 and 12 mo of follow-up. Throughout the intervention, intakes of protein and energy were similar with all 3 eating patterns, with comparable reductions in body weight (5%−7%) and visceral fat volume (12%−17%) after 12 mo. After 3 mo, ghrelin increased significantly with the acellular (mean: 46 pg/mL; 95% CI: 11, 81) and cellular (mean: 54 pg/mL; 95% CI: 21, 88) diets but not with the LCHF diet (mean: 11 pg/mL; 95% CI: −16, 38). Although βHB increased significantly more with the LCHF diet than with the acellular diet after 3 m (mean: 0.16 mmol/L; 95% CI: 0.09, 0.24), this did not correspond to a significant group difference in ghrelin (unless the 2 high-carbohydrate groups were combined [mean: −39.6 pg/mL; 95% CI: −76, −3.3]). No significant between-group differences were seen in feelings of hunger. ConclusionsModestly energy-restricted isocaloric diets differing in carbohydrate cellularity and amount showed no significant differences in fasting total ghrelin or subjective hunger feelings. An increase in ketones with the LCHF diet to 0.3–0.4 mmol/L was insufficient to substantially curb increases in fasting ghrelin during fat loss.

Glycaemic and Appetite Suppression Effect of a Vegetable-Enriched Bread.

Bread, a frequently consumed food, is an ideal vehicle for addition of ingredients that increase nutrient density and add health benefits. This experimental cross-over study sought to test the effect of a vegetable-enriched bread (VB) in comparison to commercial white bread (WB) and wheatmeal bread (WMB) on serum glucose, insulin response and subjective appetite suppression. On three separate occasions, 10 participants (23 ± 7 years) visited the laboratory and consumed after an overnight fast, in random order, a 75 g serve of WB, WMB or VB. Venous blood samples drawn twice before (0 min) and at 15, 30, 45, 60, 90 and 120 min after consumption of the bread were analysed for glucose and insulin. Participants rated their subjective feelings of hunger, fullness, satisfaction and desire to eat on a 150 mm Likert scale. The mean glucose iAUC over 120 min was not different among the breads. The mean insulin iAUC for the VB was significantly lower than the WB and WMB; difference VB and WB 12,415 pmol/L*minutes (95% CI 1918, 22,912 pmol/L*minutes, p = 0.025) and difference VB and WMB 13,800 pmol/L*minutes (95% CI 1623, 25,976 pmol/L*minutes p = 0.031). The VB was associated with a higher fullness feeling in the participants over the 120-min period. The consumption of VB was associated with less insulin release and higher satiety over 120 min which may be related to the higher fibre content and texture of VB. The role of vegetable and fruit fibres such as pectin in bread and insulin response should also be further explored.

Reassessing relationships between appetite and adiposity in people at risk of obesity: A twin study using fMRI

BackgroundNeuroimaging studies suggest that appetitive drive is enhanced in obesity. ObjectiveTo test if appetitive drive varies in direct proportion to the level of body adiposity after accounting for genetic factors that contribute to both brain response and obesity risk. Subjects/MethodsParticipants were adult monozygotic (n = 54) and dizygotic (n = 30) twins with at least one member of the pair with obesity. Body composition was assessed by dual-energy X-ray absorptiometry. Hormonal and appetite measures were obtained in response to a standardized meal that provided 20% of estimated daily caloric needs and to an ad libitum buffet meal. Pre- and post-meal functional magnetic resonance imaging (fMRI) assessed brain response to visual food cues in a set of a priori appetite-regulating regions. Exploratory voxelwise analyses outside a priori regions were performed with correction for multiple comparisons. ResultsIn a group of 84 adults, the majority with obesity (75%), body fat mass was not associated with hormonal responses to a meal (glucose, insulin, glucagon-like peptide-1 and ghrelin, all P>0.40), subjective feelings of hunger (β=−0.01 mm [95% CI −0.35, 0.34] P = 0.97) and fullness (β=0.15 mm [−0.15, 0.44] P = 0.33), or buffet meal intake in relation to estimated daily caloric needs (β=0.28% [−0.05, 0.60] P = 0.10). Body fat mass was also not associated with brain response to high-calorie food cues in appetite-regulating regions (Pre-meal β=−0.12 [−0.32, 0.09] P = 0.26; Post-meal β=0.18 [−0.02, 0.37] P = 0.09; Change by a meal β=0.29 [−0.02, 0.61] P = 0.07). Conversely, lower fat mass was associated with being weight reduced (β=−0.05% [−0.07, −0.03] P<0.001) and greater pre-meal activation to high-calorie food cues in the dorsolateral prefrontal cortex (Z = 3.63 P = 0.017). ConclusionsIn a large study of adult twins, the majority with overweight or obesity, the level of adiposity was not associated with excess appetitive drive as assessed by behavioral, hormonal, or fMRI measures.

Appetite-Related Hormones and Subjective Feelings of Hunger and Satiety in Adults Who Regularly Consume Dairy and Those Who Limit Dairy Consumption

Abstract Objectives To compare self-reported feelings of hunger and fullness with biological markers associated with appetite and satiety in men and women who are habitual dairy consumers (DC) vs limited dairy consumers (LD). We hypothesize that the DC group will have different appetite perceptions along with different concentrations of the hunger hormone, ghrelin, and the anabolic hormone, insulin, before and following a mixed meal challenge. Methods Adults from a cross-sectional study who completed the Block food frequency questionnaire were categorized as DC (n = 40, consumed &amp;gt;2 cup-eq/d of milk, yogurt, and/or cheese), or LD (n = 37, consumed &amp;lt; ½ cup-eq/d of dairy). On a test day, overnight fasted and postprandial blood samples were collected after a (non-dairy) mixed meal challenge at 30 min, 3h, and 6h. Feelings of hunger, fullness, desire to eat, and prospective consumption were measured by visual analog scales (VAS) in the fasted state, and immediately following the mixed meal at 20 min, 40 min, 1h, 1.5h, 2h, 3h, 4h, 5h, and 6 h. Differences in VAS ratings, fasting glucose, insulin, and ghrelin, and 6-h incremental area under the curve (iAUC) between groups were analyzed using t-tests. Results The DC group had lower mean fasting ghrelin (P &amp;lt; 0.001) and higher fasting glucose (P &amp;lt; 0.05) compared to LD. Fasting insulin levels were not different between groups (P = 0.87), nor were there differences for 6-h iAUC for glucose, ghrelin, or insulin. Hunger, fullness, desire to eat, and prospective consumption, summarized as 6-h AUC, were not different between groups. No correlations were found between hormone concentrations and feelings of hunger, fullness, desire to eat, or prospective consumption, at fasting or 30 min, 3h or 6h following meal challenge. Conclusions Regular consumption of ≥2 cup-eq. of dairy was associated with a reduced fasting ghrelin that might signal less hunger compared to low dairy consumers, but no relationship between ghrelin and hunger was found. The postprandial response in ghrelin, glucose, and insulin were not influenced by habitual dairy consumption. Funding Sources Funding was provided by the United States Department of Agriculture and Arla Foods Inc.

Effect of Acute Sprint Exercise on Myokines and Food Intake Hormones in Young Healthy Men.

Physical exercise is known to influence hormonal mediators of appetite, but the effect of short-term maximal intensity exercise on plasma levels of appetite hormones and cytokines has been little studied. We investigated the effect of a 30 s Wingate Test, followed by a postprandial period, on appetite sensations, food intake, and appetite hormones. Twenty-six physically active young males rated their subjective feelings of hunger, prospective food consumption, and fatigue on visual analogue scales at baseline, after exercise was completed, and during the postprandial period. Blood samples were obtained for the measurement of nesfatin-1, ghrelin, leptin, insulin, pancreatic polypeptide (PP), human growth factor (hGH) and cytokine interleukin-6 (IL-6), irisin and plasma lactate concentrations, at 30 min before exercise, immediately (210 s) after exercise, and 30 min following a meal and at corresponding times in control sedentary males without ad libitum meal intake, respectively. Appetite perceptions and food intake were decreased in response to exercise. Plasma levels of irisin, IL-6, lactate, nesfatin-1 and ghrelin was increased after exercise and then it was returned to postprandial/control period in both groups. A significant rise in plasma insulin, hGH and PP levels after exercise was observed while meal intake potentiated this response. In conclusion, an acute short-term fatiguing exercise can transiently suppress hunger sensations and food intake in humans. We postulate that this physiological response involves exercise-induced alterations in plasma hormones and the release of myokines such as irisin and IL-6, and supports the notion of existence of the skeletal muscle–brain–gut axis. Nevertheless, the detailed relationship between acute exercise releasing myokines, appetite sensations and impairment of this axis leading to several diseases should be further examined.

Disinhibition and Subjective Hunger as Mediators Between Weight Bias Internalization and Binge Eating Among Pre-Surgical Bariatric Patients.

Weight bias internalization, or the process of applying negative weight-related attitudes and beliefs to oneself, is an important construct in regard to patients pursuing bariatric surgery. Weight bias internalization (or internalized weight bias) has been previously associated with depressive symptoms and binge eating among pre-surgical bariatric patients. However, a gap in the literature exists pertaining to how certain eating behaviors may mediate the relationship between weight bias internalization and binge eating. The present study assessed the role of eating behaviors (i.e., cognitive restraint, disinhibition, and hunger) as mediators between weight bias internalization and binge eating symptoms when controlling for depression. A total of 708 adults (Mage = 42.91; White = 95.3%; women = 79.4%) seeking bariatric surgery at a tertiary academic medical center in the Appalachia region of the USA were included in this retrospective study. Patients completed validated measures of weight bias internalization, eating behaviors, and depression as part of a routine, psychological evaluation in order to determine surgical clearance. Disinhibition and hunger were significant mediators in the relationship between weight bias internalization and binge eating beyond the role of depressive symptoms alone. Disinhibited eating, or the tendency to experience a loss of control and eating in response to negative emotions, as well as subjective feelings of hunger are important dimensions of eating, particularly as related to weight bias internalization and binge eating. Weight bias internalization is an important factor to consider among pre-surgical bariatric patients and warrants additional treatment considerations.

Virtual grocery shopping and cookie consumption following intranasal insulin or placebo application.

Insulin receptors are present in brain areas that are involved in the control of hunger and satiety, and intranasal insulin is assumed to have an anorexigenic effect. This known influence of insulin on satiety encouraged us to investigate the effect of intranasal insulin on feeding-related behaviors. The aim of the current study was to explore the influence of 40 IU of intranasal insulin on the grocery shopping behavior and cookie consumption in a group of 30 healthy young men, using a crossover randomized double-blind design. Using a virtual mock supermarket, we tested whether the intranasal administration of insulin influences purchase behavior in comparison to a placebo or control condition. The participants also provided hedonic ratings of food pictures, as well as their subjective feeling of hunger. We calculated an objective measure of hunger from the amount of cookies eaten. In contradiction to our hypotheses, no significant differences regarding ratings, calorie content of purchased food products, and cookie consumption were found between the treatment conditions. Our conclusion is that 40 IU intranasal insulin had no influence on the evaluation of pictured foods in healthy young men in our task. Acknowledging that previous studies have found effects for intranasal insulin and food cue processing, we suggest that future research should focus on chemosensory stimulation or cognitive tasks in behavioral experiments and carefully consider the doses of intranasal insulin. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Changes in the Homeostatic Appetite System After Weight Loss Reflect a Normalization Toward a Lower Body Weight.

ObjectiveTo compare appetite markers in reduced-obese individuals with a nonobese control group.MethodsA total of 34 adults with obesity who lost 17% body weight at week 13 and maintained this weight loss (WL) at 1 year were compared with 33 nonobese controls matched for body composition. Basal and postprandial subjective appetite ratings and appetite-related hormone concentrations (ghrelin, total peptide YY, peptide YY3-36, total and active glucagon-like peptide 1, and cholecystokinin) were measured in all participants and repeated at week 13 and 1 year in the weight-reduced group.ResultsWL led to a reduction in prospective food consumption and an increase in feelings of hunger, fullness, and ghrelin secretion (basal and postprandial), but these new ratings were no different from those seen in controls. Postprandial concentrations of active glucagon-like peptide 1, total peptide YY, and cholecystokinin were lower in individuals with obesity at all time points compared with controls.ConclusionThe increased drive to eat (both subjective feelings of hunger and ghrelin concentrations) seen in reduced-obese individuals, both after acute and sustained WL, reflects a normalization toward a lower body weight. Overall, WL does not have a sustained negative impact on satiety peptide secretion, despite a blunted secretion in individuals with obesity compared with nonobese controls.

Acute after-school screen time in children decreases impulse control and activation toward high-calorie food stimuli in brain regions related to reward and attention.

The purpose of this study was to examine the effects of after-school sedentary screen time on children's brain activation in reward and cognitive control regions in response to pictures of high- and low-calorie foods. Thirty-two children participated in a randomized crossover study with counterbalanced treatment conditions. Conditions took place on separate days after school and included three hours of active or sedentary play. After each condition, neural activation was assessed using functional magnetic resonance imaging (fMRI) while participants completed a go/no-go task involving pictures of high- and low-calorie foods. General response inhibition was also measured using the Stroop task. Hunger was measured upon arrival to the testing facility and just prior to fMRI scans. Mixed effects models were used to evaluate main effects and interactions. Significant stimulus by condition interactions were found in the right superior parietal cortex, and left anterior cingulate cortex (Ps ≤ 0.05). High-calorie pictures elicited significantly more activation bilaterally in the orbitofrontal cortex compared to low-calorie pictures (Ps ≤ 0.05). Stroop task performance diminished significantly following the sedentary condition compared to the active (P ≤ 0.05). Subjective feelings of hunger were not different between conditions at any point. Sedentary screen time was associated with significantly decreased response inhibition and a reversed brain activation pattern to pictures of high- and low-calorie foods compared to active play, in areas of the brain important to the modulation of food intake. Decreased attention, and impulse control following sedentary screen time may contribute to disinhibited eating that can lead to overweight and obesity.

Can't take my eyes off you – How task irrelevant pictures of food influence attentional selection

By means of event-related potentials (ERPs), the present study intended to extend previous findings on how the different processing stages of attentional selection are altered by the participants' motivational state depending on their saturation level. Forty-four normal-weight (mean BMI: 21.34, SD = 1.54), healthy participants aged between 19 and 34 years were assigned to a condition of hunger or satiety. While participants performed a central oddball task, task-irrelevant pictures (food vs. neutral) were presented unilaterally (either left or right from fixation) or bilaterally. Additionally, participants' eating and nutrition behaviour as well as their current level of hunger were assessed by self-reports. The results showed that while on the behavioural level groups did not show any differences in RTs and accuracy, ERPs of hungry participants show an enhanced early parieto-occipital activity 100–200 ms after stimulus onset (N1pc) for food pictures, particularly for high-calorie food. Furthermore, amplitudes of the N1pc co-varied significantly with the participants’ subjective feeling of hunger. 200–300 ms after stimulus onset, P2pc in hungry participants reveal a lack of differential processing of the food and neutral stimuli. Between 300 and 400 ms, food pictures were associated with an enlarged centro-parietal positivity (P3) in hungry compared to satiated participants, again especially for high-calorie food stimuli. From the perspective of motivated attention, the results of the present study suggest, that hunger may induce a state of heightened attention for food stimuli, although they were completely irrelevant for the current task. By that, salient food stimuli had an influence on early automatic attentional selection as well as on later and rather intention-driven processes of attentional “de-selection” and stimulus maintenance in normal-weight participants.

Acute effect of smoking and smoking abstinence on energy intake and appetite-related hormones blood concentrations

The effect of smoking on energy balance and the underlying mechanisms are not fully understood. The aim of the present study is to examine the acute effect of smoking and its abstinence on energy intake, subjective feelings of appetite and related hormones. Fourteen healthy smokers participated in a randomized, crossover study consisting of two trials: the Cigarette trial (participants smoked two cigarettes of their brand within 15min) and the Sham trial (they were asked to hold the cigarette as smoking, but without lighting it). After 45min the participants were offered an ad libitum variety of snacks, and their intake was recorded. Blood samples were taken at fasting, before the ad libitum meal and 1h after and were analyzed for obestatin, ghrelin, glucagon-like peptide-1, cholecystokinin and insulin levels. Subjective feelings of hunger, satiety and desired to eat, as well as smoking craving were evaluated by visual analog scales. Mean energy intake at the ad libitum meal was 825±310kcal in the Sham trial and 673±245kcal in the Cigarette trial (p=0.010). No significant intervention effects were observed for the reported appetite feelings or the appetite-related hormones levels. In conclusion, smoking was found to have an acute effect on dietary intake; this was not explained by changes in the hormonal levels that were evaluated. More research is needed to confirm these results in more prolonged periods of abstinence and explore other pathways through which smoking and its abstinence affect energy balance.

Intranasal insulin enhances brain functional connectivity mediating the relationship between adiposity and subjective feeling of hunger

Brain insulin sensitivity is an important link between metabolism and cognitive dysfunction. Intranasal insulin is a promising tool to investigate central insulin action in humans. We evaluated the acute effects of 160 U intranasal insulin on resting-state brain functional connectivity in healthy young adults. Twenty-five lean and twenty-two overweight and obese participants underwent functional magnetic resonance imaging, on two separate days, before and after intranasal insulin or placebo application. Insulin compared to placebo administration resulted in increased functional connectivity between the prefrontal regions of the default-mode network and the hippocampus as well as the hypothalamus. The change in hippocampal functional connectivity significantly correlated with visceral adipose tissue and the change in subjective feeling of hunger after intranasal insulin. Mediation analysis revealed that the intranasal insulin induced hippocampal functional connectivity increase served as a mediator, suppressing the relationship between visceral adipose tissue and hunger. The insulin-induced hypothalamic functional connectivity change showed a significant interaction with peripheral insulin sensitivity. Only participants with high peripheral insulin sensitivity showed a boost in hypothalamic functional connectivity. Hence, brain insulin action may regulate eating behavior and facilitate weight loss by modifying brain functional connectivity within and between cognitive and homeostatic brain regions.

The motilin receptor agonist erythromycin stimulates hunger and food intake through a cholinergic pathway

AbstractBackground: Motilin-induced phase III contractions have been identified as a hunger signal. These phase III contractions occur as part of the migrating motor complex (MMC), a contractility pattern of the gastrointestinal tract during fasting. The mechanism involved in this association between subjective hunger feelings and gastrointestinal motility during the MMC is largely unknown, however, as is its ability to stimulate food intake.Objectives: We sought to 1) investigate the occurrence of hunger peaks and their relation to phase III contractions, 2) evaluate whether this relation was cholinergically driven, and 3) assess the ability of the motilin receptor agonist erythromycin to induce food intake.Design: An algorithm was developed to detect hunger peaks. The association with phase III contractions was studied in 14 healthy volunteers [50% men; mean ± SEM age: 25 ± 2 y; mean ± SEM body mass index (BMI; in kg/m2): 23 ± 1]. The impact of pharmacologically induced phase III contractions on the occurrence of hunger peaks and the involvement of a cholinergic pathway were assessed in 14 healthy volunteers (43% men; age: 29 ± 3 y; BMI: 23 ± 1). Last, the effect of erythromycin administration on food intake was examined in 15 healthy volunteers (40% men; age: 28 ± 3 y; BMI: 22 ± 1).Results: The occurrence of hunger peaks and their significant association with phase III contractions was confirmed (P < 0.0001). Pharmacologically induced phase III contractions were also significantly associated with hunger peaks (P < 0.05), and this association involved a cholinergic pathway. Administering erythromycin significantly stimulated food intake compared with placebo (53% ± 13% compared with 10% ± 5%; P < 0.05).Conclusions: Motilin-induced phase III contractions induced hunger feelings through a cholinergic pathway. Moreover, erythromycin stimulated food intake, suggesting a physiologic role of motilin as an orexigenic signal from the gastrointestinal tract. This trial was registered at www.clinicaltrials.gov as NCT02633579.

Ghrelin, GLP-1, and leptin responses during exposure to moderate hypoxia.

Severe hypoxia has been indicated to cause acute changes in appetite-related hormones, which attenuate perceived appetite. However, the effects of moderate hypoxia on appetite-related hormonal regulation and perceived appetite have not been elucidated. Therefore, we examined the effects of moderate hypoxia on appetite-related hormonal regulation and perceived appetite. Eight healthy males (21.0 ± 0.6 years; 173 ± 2.3 cm; 70.6 ± 5.0 kg; 23.4 ± 1.1 kg/m(2)) completed two experimental trials on separate days: a rest trial in normoxia (FiO2 = 20.9%) and a rest trial in hypoxia (FiO2 = 15.0%). The experimental trials were performed over 7 h in an environmental chamber. Blood samples and scores of subjective appetite were collected over 7 h. Standard meals were provided 1 h (745 kcal) and 4 h (731 kcal) after initiating exposure to hypoxia or normoxia within the chamber. Although each meal significantly reduced plasma active ghrelin concentrations (P < 0.05), the response did not differ significantly between the trials over 7 h. No significant differences in the area under the curves for plasma active ghrelin concentrations over 7 h were observed between the two trials. No significant differences were observed in glucagon-like peptide 1 or leptin concentrations over 7 h between the trials. The subjective feeling of hunger and fullness acutely changed in response to meal ingestions. However, these responses were not affected by exposure to moderate hypoxia. In conclusion, 7 h of exposure to moderate hypoxia did not change appetite-related hormonal responses or perceived appetite in healthy males.

The influence of environmental temperature on appetite-related hormonal responses.

BackgroundAcute exercise in the heat has been shown to reduce appetite. However, the influence of exercise in the cold on appetite regulation remains unclear. The aim of this study was to compare exercise-induced appetite regulation under three different environmental temperatures.MethodsEleven male participants completed three experimental trials on the following separate days: exercise in the heat (36°C), exercise at neutral temperature (24°C), and exercise in the cold (12°C). The exercise trials consisted of pedaling exercises for 30 min at 65% of maximal oxygen uptake (VO2max). Blood samples were collected repeatedly to determine plasma ghrelin, peptide YY (PYY) and other hormonal concentrations. Subjective feelings of hunger and tympanic temperature were also monitored.ResultsTympanic temperature was significantly higher in the 36°C trial than that of the other two trials (P < 0.05). The subjective feelings of hunger in the 36°C and 24°C trials were significantly lower than those in the 12°C trial (P < 0.05). Plasma ghrelin concentration decreased significantly with exercise in all conditions (P < 0.05), and the responses were not significantly different among the three conditions. Plasma PYY concentration increased significantly after the exercise in the 24°C trial only (P < 0.05), with no significant difference among the three trials.ConclusionsThese results suggest that exposure to hot or cold temperatures during exercise did not affect exercise-induced plasma ghrelin and PYY responses. However, the exercise-induced reduction of subjective hunger was significantly attenuated in a cold environment.

Postprandial effects of polydextrose on satiety hormone responses and subjective feelings of appetite in obese participants.

BackgroundDietary fibers are associated with enhanced satiety. However, the mechanism of different dietary fibers contributing to satiety-related gastrointestinal (GI) peptide release, especially in an obese population, is still poorly understood. Polydextrose (PDX), a water-soluble glucose polymer, has demonstrated its ability to reduce energy intake at a subsequent meal, but its mechanism of action requires further research. Also, there is limited evidence on its capacity to regulate subjective feelings of appetite. This study examines the effects of PDX on postprandial secretion of satiety-related GI peptides, short chain fatty acids (SCFAs), lactic acid, and subjective appetite ratings in obese participants.Methods18 non-diabetic, obese participants (42.0 y, 33.6 kg/m2) consumed a high-fat meal (4293 kJ, 36% from fat) with or without PDX (15 g) in an acute, multicenter, randomized, double-blind, placebo-controlled and crossover trial. Postprandial plasma concentrations of satiety-related peptides, namely ghrelin, cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), and peptide YY (PYY), as well as SCFAs and lactic acid were assessed. GI peptide, SCFA and lactate concentrations were then modeled using a linear mixed-effects model.The subjective feelings of hunger, satisfaction, and desire to eat were evaluated using visual analogue scales (VAS), which were analyzed as incremental areas under the curve (iAUC) during the satiation and satiety periods.ResultsWe found that PDX supplementation increased plasma GLP-1 levels more than the placebo treatment (P = 0.02). In the whole group, GLP-1 concentrations found in participants older than 40 years old were significantly lower (P = 0.01) as compared to those aged 40 years or less. There were no statistically significant differences in postprandial ghrelin, CCK, or PYY responses. The lactic acid concentrations were significantly (P = 0.01) decreased in the PDX group, while no significant changes in SCFAs were found. PDX reduced iAUC for hunger by 40% (P = 0.03) and marginally increased satisfaction by 22.5% (P = 0.08) during the post-meal satiety period.ConclusionPolydextrose increased the postprandial secretion of the satiety hormone GLP-1 and reduced hunger after a high-fat meal. PDX also reduced the elevated postprandial lactic acid levels in plasma. Therefore, PDX may offer an additional means to regulate inter-meal satiety and improve postprandial metabolism in obese participants.

Effect of movie violence on mood, stress, appetite perception and food preferences in a random population.

Very little is known about media violence and its effect on appetite and eating behavior. The present study aims at investigating the immediate acute effect of violence in movies on mood, stress, appetite perception and food preferences in a real-life setting. A total of 447 subjects (F = 202; M = 239) completed a validated visual analog scale to record their subjective feelings of hunger, satiety and desire to eat immediately at their way out of any of the three types of movies (horror, romance/comedy and drama/action). There was a significant difference between the three movie categories for the tensed feeling (P = 0.003), anxiety (P = 0.021), the sleepy feeling (P = 0.000) and a preference to eat something sweet (P = 0.019). Horror/violence movie types affected the subject by making him feel more stressed and anxious; however, romance made him feel sleepier and less tensed. Movie types did not seem to affect hunger or appetite directly, but rather triggered some food preferences.

Molecular weight of barley β-glucan does not influence satiety or energy intake in healthy male subjects

Previous studies have shown the ability of high molecular weight barley β-glucan with increased viscosity to attenuate glycemic response, gastric emptying and in vitro starch digestion. The main objective of this study was to investigate the effect of molecular weight of barley β-glucan in a semisolid meal on energy intake and subjective feelings of hunger, fullness, desire to eat and prospective food consumption in healthy male subjects. In a randomised, controlled, crossover trial, 23 healthy male subjects (BMI 24.2 ± 2.5 kg/m2) tested soups equivalent to 25 g available carbohydrate containing high or low molecular weight barley β-glucan (~3 g) as preload after a standard breakfast. The viscosity of soup with high molecular weight β-glucan was 350 Pa·s whereas the soup with low molecular weight β-glucan had a viscosity of 100 Pa·s. Appetite ratings before and for two hours after consumption of β-glucan soups and subsequent ad libitum energy intake at lunch were recorded and compared with a control soup with no β-glucan. There was no significant difference in food intake at the ad libitum meal or for the remainder of the day following consumption of the three test foods (p > 0.05). Similarly, there were no significant differences (p > 0.05) in hunger, fullness, desire to eat or prospective food consumption following β-glucan soups. The current study provides evidence that the molecular weight of barley β-glucan may not impact on perceived feelings of hunger or food intake at the current dose and viscosity.

A Mediterranean-like breakfast affects energy intake and appetite-related feelings

Energy intake and appetite feelings after the consumption of two different types of breakfast, a high-fiber, traditional, Mediterranean-type breakfast and a low-fiber, Western-type breakfast were compared. Sixteen non-obese young men received the two treatments on separate days: the Mediterranean- and the Western-type breakfasts were isocaloric, similar in volume and macronutrient content, but different in fiber content. Following a 4-hour fast, subjects offered an ad libitum lunch. Food consumed and subjective feelings of hunger, fullness, and desire to eat were evaluated. Energy intake in the ad libitum lunch was significantly lower after the Mediterranean-type, compared to the Western-type breakfast, adjusting for previous day’s energy intake (1488 ± 468 versus 1674 ± 416 kcal, respectively), whereas no energy compensation was made throughout the day. Furthermore, those who had the Mediterranean-type breakfast reported lower values in the desire to eat during study's course. These findings propose a fulfilling effect of a traditional, Mediterranean, high in fiber breakfast.