Subjective Feelings Of Appetite Research Articles

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.

Effects of the maize-derived protein zein, and the milk proteins casein, whey, and α-lactalbumin, on subjective measures of satiety and food intake in normal-weight young men

Protein is considered to be the most satiating food macronutrient and the satiating effect may be dependent on the source of the protein. The maize-derived protein zein and milk protein casein have been shown previously to lower stomach emptying rate more than dairy whey protein, but the effect of zein on satiety has not been evaluated. The objective was to compare the satiating effects of zein and casein, with whey protein and its protein component α-lactalbumin. The study was a randomised crossover design with thirteen normal-weight men (mean age 27.8 years and mean BMI 24.4 kg/m2) consuming isoenergetic (∼4000 kJ, ∼990 kcal) preload mixed meals enriched with Zein, Casein, whey protein isolate (Whey), α-lactalbumin (ALac), or maltodextrin carbohydrate (Carb). Consumption of an ad libitum standardised test meal of chicken fried rice and water provided 360 min following ingestion of the preload meal was measured, and subjective feelings of appetite (hunger, fullness, desire to eat, and prospective food consumption) were assessed using 100-mm visual analogue scales (VAS). There were no differences among the five preload mixed meals in the amount of chicken fried rice consumed at the ad libitum test meal (mean ± sem: 531.6 ± 35.0 g, p = 0.47) or total (preload + test meal) energy intakes (mean ± sem: 5780.5 ± 146.0 kJ, p = 0.29). The subjective VAS appetite ratings and total area under the curve responses for hunger, fullness, desire to eat, and prospective food consumption, were not different following consumption of all five preload mixed meals (p > 0.05). The findings indicate that the effects of zein and casein on satiety were not different from the satiating effects of whey protein and α-lactalbumin.

Short-term effects of milkshake containing polydextrose and maltodextrin on subjective feelings of appetite, energy intake and blood glucose in healthy females

PurposePrevious studies have reported that dietary fibers such as polydextrose and maltodextrin can reduce food intake; however, the studies on the differences of this effect are insufficient. The purpose of this paper is to compare the effects of dietary fibers maltodextrin and polydextrose on alterations of short-term satiety, energy intake and postprandial blood glucose in healthy females.Design/methodology/approachThis study was designed as a randomized, crossover and double blind research. For this purpose, 21 healthy females consumed a milkshake containing 0 g (control), 15 g polydextrose (PDX) and 15 g maltodextrin (MDX), and an ad libitum lunch meal was served 150 min later. Subjective appetite scores (hunger, satiety, prospective food consumption and desire to eat) were measured using a visual analog scale. Appetite scores and blood glucose were measured before preload and once per 15 min after milkshake consumption.FindingsVisual analog scale scores showed that PDX had an improved effect on satiety and hunger feelings. Compared to the control, dietary fiber increased the Area Under Curve (AUC) scores of satiety (p < 0.001) and decreased the AUC scores of hunger (p < 0.001), prospective food consumption (p < 0.001) and desire to eat (p < 0.001). Energy intake during ad libitum meal was significantly lower in PDX (Control: 862 (54.3) Kcal versus PDX: 679 (35.4) Kcal and MDX: 780 (49.3) Kcal. Moreover, the blood glucose levels were significantly lower in MDX.Originality/valueThis study conducted with healthy females demonstrated that PDX was more effective in inducing satiety during subsequent food intake, and that postprandial blood glucose were within more healthy levels in MDX.

Effects of Acute Dance and Aerobic Exercise on Drug Craving and Food Reward in Women with Methamphetamine Dependence.

Drug dependence causes an overestimation of drug-related stimuli and an underestimation of non-drug-related stimuli, such as food. The purpose of this study was to investigate the effects of acute moderate-intensity dance and aerobic exercise on drug craving, appetite, prefrontal neural activation to food cues, and food reward in women with methamphetamine MA dependence. Thirty-nine women who met the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition MA dependence criteria participated in the experiment and were randomly assigned to either a dance (n = 20) or exercise (n = 19) group. A moderate-intensity (65%-75% maximum heart rate) 35-min dance or treadmill intervention counterbalanced with a reading control session was conducted. After the intervention or control, subjective drug craving was measured before and after exposure to drug-related cues. Visual analog scales were used to measure subjective feelings of appetite. Participants then completed a visual food cue paradigm while using functional near-infrared spectroscopy to monitor prefrontal blood oxygen changes. Finally, the Leeds Food Preference Questionnaire was used to measure reward responses to different categories of food. The results showed that the dance and exercise interventions reduced subjective craving for drugs after being exposed to drug cues (P = 0.019). Implicit wanting (P < 0.001) and relative preferences (P = 0.001) for high-calorie savory foods were all increased after interventions relative to control. Compared with the control session, the left dorsolateral prefrontal cortex (P = 0.020) was activated when viewing high-calorie foods after moderate-intensity aerobic exercise. The current results support the use of moderate-intensity exercise as a therapeutic intervention to restore the balance between drug and nondrug rewards by decreasing cue-induced MA craving and increasing food reward.

Association between habitual sleep duration/quality and appetite markers in individuals with obesity

Study ObjectivesTo assess if habitual sleep duration/quality was associated with appetite in individuals with obesity, and if the association was modulated by sex. MethodsSleep duration/quality was measured with Pittsburgh Sleep Quality Index score in 95 healthy adults with obesity (BMI: 36.6 ± 4.2 kg/m2). Subjective feelings of appetite were assessed using visual analogue scales, and plasma concentrations of active ghrelin, total peptide YY, active glucagon-like peptide 1, cholecystokinin (CCK) and insulin were measured in fasting and every 30 min up to 2.5 h after a meal. ResultsNo significant associations were found between sleep duration, or overall quality, and appetite in all participants. However, a worse sleep efficiency was associated with lower postprandial CCK, a shorter habitual sleep was associated with lower postprandial desire to eat and a lower daytime dysfunction was associated with higher prospective food consumption in fasting (P<0.05, for all). In males, a shorter habitual sleep duration and a worse subjective sleep quality were associated with increased basal and postprandial active ghrelin (P<0.05, P<0.01, P<0.01 and P<0.05, respectively). Also, a shorter habitual sleep was associated with lower basal and postprandial insulin (P<0.05 for both) and a worse overall sleep quality with lower postprandial insulin (P<0.05). In females, a worse overall sleep quality was associated with lower postprandial active ghrelin (P<0.05), and short habitual sleep with higher postprandial insulin (P<0.05). ConclusionA worse habitual sleep efficiency is associated with blunted postprandial CCK secretion in individuals with obesity. The association between habitual sleep duration/quality and insulin and active ghrelin seems to be modulated by sex, but more studies are needed to confirm these findings.

Fortificación con fibra dietética como estrategia para aumentar la saciedad: ensayo aleatorizado doble ciego controlado

Introducción: Se ha descrito que las fibras dietéticas (FD) podrían tener efectos favorables en el control de sentimientos subjetivos relacionados a sensaciones postprandiales de apetito y saciedad, propiedad que en el contexto epidemiológico actual podrían ser beneficiosos. Objetivo: Evaluar el efecto agudo de 3 tipos de FD sobre la percepción subjetiva de sensaciones postprandiales. Material y métodos: Estudio randomizado, doble ciego, controlado, cruzado. 21 sujetos sanos con índice de masa corporal entre 18.5-24.9 Kg/m2, fueron asignados aleatoriamente para consumir 4 desayunos separados por a lo menos 2 días. Los desayunos fueron fortificados con 3 g de: β-glucano de avena (BETA), pectinas de manzana (PECT), celulosa microcristalina (CELL) y maltodextrina como control (MALT). Los sentimientos subjetivos postprandiales se determinaron con una Encuesta Visual Análoga (EVA) antes del desayuno y a los 15, 30, 60, 90 y 120 min. Resultados: En análisis de varianzas (ANOVA) mostró una diferencia significativa a los 15 minutos (p&lt;0,05) en la percepción de saciedad subjetiva de los desayunos fortificados con pectina de manzana versus β-glucano de avena. β-glucano de avena produjo el menor efecto en la saciedad subjetiva (p&lt;0,05). Un ANOVA de medidas repetidas no mostró efectos de los tipos de fibras adicionadas a los desayunos en el sentimiento subjetivo de apetito. Conclusiones: Las pectinas de manzana parecen ser más efectiva que otros tipos de FD para aumentar la percepción subjetiva de saciedad y disminuir el apetito, especialmente en el periodo postprandial temprano.

Association Between Ketosis and Changes in Appetite Markers with Weight Loss Following a Very Low-Energy Diet.

The purpose of this study was to examine whether the degree of ketosis, measured as plasma β-hydroxybutyrate (βHB) in fasting, was associated with changes in appetite feelings and plasma concentration of appetite-related hormones after weight loss. A total of 87 individuals with obesity (BMI: 36.5 ± 4.0 kg/m2 ; age: 42.4 ± 9.7 years; 39 males) underwent 8 weeks of a very low-energy diet. Body weight/composition, plasma concentration of βHB, and appetite-related hormones (active ghrelin, active glucagon-like peptide 1 [GLP-1], total peptide YY, cholecystokinin [CCK], and insulin) and subjective appetite feelings were measured at baseline and week 9. Participants lost 17.7 ± 4.1 kg and were ketotic (βHB: 1.24 ± 0.82 mmol/L in fasting) at week 9. A negative association was found between βHB in fasting at week 9 and changes in basal (r = -0.315, P = 0.003) and postprandial ghrelin concentration (r = -0.286, P = 0.008), and a positive association was found with the change in postprandial GLP-1 (r = 0.244, P = 0.025) and CCK (r = 0.228, P = 0.035). No association was seen between βHB in fasting and changes in peptide YY or subjective feelings of appetite. βHB plasma concentration in fasting is associated with lower concentrations of the hunger hormone ghrelin and increased concentrations of the satiety hormones GLP-1 and CCK. Future studies should explore the molecular mechanisms by which βHB modulates the secretion of gut hormones.

MON-589 Studying Mechanisms of Satiety in the Human Ileum and Colon

Background The gut-brain axis plays important roles in the regulation of appetite and glucose homeostasis. The presence of nutrients and their digestive products in specific regions of the gastrointestinal tract modulates neuronal and hormonal signalling, including the release of the appetite-suppressing gut hormones glucagon-like peptide-1 (GLP-1) and peptide YY (PYY). While there has been significant research into the upper gut mechanisms behind satiation, i.e. the termination of meal, the role of the ileum and colon in satiety, i.e. the process which delays a subsequent meal, has been relatively little investigated, particularly in humans. Methods Ten healthy volunteers attended our Clinical Research Facility for two visits of four days each. At each visit they had either a nasoileal or a nasocolonic tube inserted under fluoroscopy. They were then provided a diet rich in protein and fibre to promote satiety. Gut contents and blood samples were taken before and during test meals at the start and end of the visit, and visual analogue scales were used to measure subjective feelings of appetite. Metabonomic analysis of gut fluid was carried out using a combination of in-house NMR and LC-MS-based methods. 16S rRNA gene sequencing was used to investigate effects on the colonic microbiome. Circulating levels of glucose, the gut hormones GLP-1 and PYY, and the pancreatic hormones insulin and glucagon were measured. Results and discussion The test meals resulted in sustained suppression of appetite and release of GLP-1 and PYY. Ileal and colonic microbial profiles were distinct from those identified in stool samples, and changed with adaptation to the high protein and fibre diet. Integrating hormonal, metabonomic and bacterial datasets from these human studies gives insight into how nutrient and metabolite sensing in the gastrointestinal tract regulates appetite and glucose homeostasis, and may suggest novel therapeutic targets for metabolic disease.

Effects of Stevia Extract on Postprandial Glucose Response, Satiety and Energy Intake: A Three-Arm Crossover Trial.

Non-nutritive sweeteners (NNS) are suggested to lower energy intake in the diet, but they have been paradoxically involved in the epidemic of obesity and Type 2 diabetes. Stevia is the least studied sweetener. This study aims to investigate the effect of stevia on postprandial glucose levels, appetite and food intake. Methods: 30 participants (20 females/10 males; 26.1 (10.56) years; body mass index (BMI) 23.44 (3.42) Kg/m2) took part in a three-arm crossover trial where they received preloads of water, sugar (60 g) and stevia (1 g) on three different days, followed by an ad libitum pizza lunch. Breakfast was standardised. A one-day diet diary was collected on each test day. Visual analogue scales (VAS) were used to assess subjective feelings of appetite. Blood glucose samples were collected at 30-min intervals until 120 min post lunch. Results: Energy intake did not significantly differ between preloads for ad libitum meals (p = 0.78) and overall day (p = 0.33). VAS scores for hunger and desire to eat (DTE) were lower following stevia preload compared to water (p < 0.05). After adjusting for the sugar preload and calorie content, postprandial glucose levels did not significantly differ between interventions. Conclusion: Stevia lowers appetite sensation and does not further increase food intake and postprandial glucose levels. It could be a useful strategy in obesity and diabetes prevention and management.

Moderate-Intensity Aerobic Exercise Restores Appetite and Prefrontal Brain Activity to Images of Food Among Persons Dependent on Methamphetamine: A Functional Near-Infrared Spectroscopy Study.

The brain prefrontal control system is critical to successful recovery from substance use disorders, and the prefrontal cortex (PFC) regulates striatal reward-related processes. Substance-dependent individuals exhibit an increased response to drug rewards and decreased response to natural, nondrug rewards. Short-term aerobic exercise can ameliorate craving and inhibitory deficits in methamphetamine users, but the effect of exercise on food reward is unknown. This study used functional near-infrared spectroscopy (fNIRS) to measure the effects of moderate- and high-intensity short-term aerobic exercise on prefrontal activity related to food images and recorded the subjective feelings of appetite in methamphetamine-dependent users. In total, 56 men who met the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) criteria for methamphetamine dependence, with a mean (SD) body mass index of 24.7 (3.5) kg/m2 and age of 30.2 (5.1) years, were randomly assigned to one of two exercise groups: moderate intensity (n = 28; 65%–75% of maximum heart rate) and high intensity (n = 28; 76%–85% of heart rate maximum). Each group also performed a resting control session for 35 min 1 week before or after the exercise, in a counterbalanced order. Mean oxygenated hemoglobin concentration changes in the PFC when viewing visual food cues were assessed by fNIRS, and subjective feelings of appetite were self-rated using visual analog scales after moderate- or high-intensity aerobic exercise and after the resting control session. A continuous-wave NIRS device was used to obtain functional data: eight sources and seven detectors were placed on the scalp covering the PFC, resulting in 20 channels per participant. We found that moderate-intensity aerobic exercise significantly increased both, the activation of the left orbitofrontal cortex (OFC) to images of high-calorie food (P = 0.02) and subjective sensations of hunger (F(1,54) = 7.16, P = 0.01). To our knowledge, this study provides the first evidence that moderate-intensity aerobic exercise increases OFC activity associated with high-calorie food images and stimulates appetite in methamphetamine-dependent individuals. These changes suggest that exercise may reestablish the food reward pathway hijacked by drugs and restore sensitivity to natural rewards. This evidence may contribute to the development of specific exercise programs for populations with methamphetamine dependence.

Effects of moderate- and high-intensity acute aerobic exercise on food reward and appetite in individuals with methamphetamine dependence

PurposeDrug addiction is characterised by overvaluation of drug-related rewards and undervaluation of “natural”, non-drug-related rewards. Methamphetamine (MA) is the second largest illegally abused drug in the world. Studies have shown that acute aerobic exercise can reduce the incidence of MA-dependent individuals' craving for drug-related cues, but the impact of exercise on food reward in this population has yet to be established. The aim of this study was to determine the effects of moderate and high-intensity acute aerobic exercise on food reward and subjective feelings of appetite in MA-dependent populations. MethodsForty-four men, who met the DSM-V criteria for MA dependence, with BMI of 24.7 ± 3.1 kg/m2 and age of 31.9 ± 3.8 years, were randomly assigned to two exercise training groups: moderate- (n = 22; 65%~75% HRmax) or high- (n = 22; ≥ 85% HRmax) intensity. Each group performed a resting control or exercise session for 35 min, 1wk apart, in a counterbalanced order. Food reward (explicit liking, implicit wanting and relative preference) for high or low fat and sweet or savoury food images was assessed by the Leeds Food Preference Questionnaire and subjective feelings of appetite were measured by VAS. ResultsGreater relative preference (high: P = .018; moderate: P = .034) and implicit wanting (high: P = .018; moderate: P = .034) for high-fat savoury foods was noted following acute aerobic exercise compared to the control session. Exercise also increased subjective sensations of hunger (F (1,42) =8.28, P = .006). ConclusionsThe current study provides the first evidence that acute aerobic exercise can increase reward for high fat savoury foods and stimulate appetite in MA-dependent individuals. In the context of exercise as a therapeutic option for MA dependence, these changes suggest an improvement in responsiveness to natural, non-drug rewards.

Investigating the effect of sex and ketosis on weight-loss-induced changes in appetite

ABSTRACTBackgroundDiet-induced weight loss (WL) is usually accompanied by increased appetite, a response that seems to be absent when ketogenic diets are used. It remains unknown if sex modulates the appetite suppressant effect of ketosis.ObjectiveThe aim of this study was to examine if sex modulates the impact of WL-induced changes in appetite and if ketosis alters these responses.MethodsNinety-five individuals (55 females) with obesity (BMI [kg/m 2]: 37 ± 4) underwent 8 wk of a very-low-energy diet, followed by 4 wk of refeeding and weight stabilization. Body composition, plasma concentration of β-hydroxybutyrate (β-HB) and appetite-related hormones (active ghrelin, active glucagon-like peptide 1 [GLP-1], total peptide YY [PYY], cholecystokinin and insulin), and subjective feelings of appetite were measured at baseline, week 9 in ketosis, and week 13 out of ketosis.ResultsThe mean WL at week 9 was 17% for males and 15% for females, which was maintained at week 13. Weight, fat, and fat-free mass loss were greater in males (P < 0.001 for all) and the increase in β-HB at week 9 higher in females (1.174 ± 0.096 compared with 0.783 ± 0.112 mmol/L, P = 0.029). Basal and postprandial GLP-1 and postprandial PYY (all P < 0.05) were significantly different for males and females. There were no significant sex × time interactions for any other appetite-related hormones or subjective feelings of appetite. At week 9, basal GLP-1 was decreased only in males (P < 0.001), whereas postprandial GLP-1 was increased only in females (P < 0.001). No significant changes in postprandial PYY were observed over time for either sex.ConclusionsKetosis appears to have a greater beneficial impact on GLP-1 in females. However, sex does not seem to modulate the changes in the secretion of other appetite-related hormones, or subjective feelings of appetite, seen with WL, regardless of the ketotic state. This trial was registered at clinicaltrials.gov as NCT01834859.

The Effect of Glucose or Fructose Added to a Semi-solid Meal on Gastric Emptying Rate, Appetite, and Blood Biochemistry.

The ingestion of fructose is of interest due to previously reported differences in gastrointestinal, appetite, and metabolic effects when compared to glucose ingestion when ingested in liquid solution. The aim of this study was to examine these variables when fructose and glucose are added to a semi-solid meal. Seven healthy male participants completed three experimental trials involving the ingestion of 300 mL of semi-skimmed milk mixed with 40 g of instant porridge mix (CON) and with the addition of either 40 g of glucose (GLU) or fructose (FRU). Subjective feelings of appetite were assessed for 2 h after ingestion with blood samples collected at regular intervals. Gastric emptying rate was assessed using the 13C breath test method. Half emptying time was not different between trials (CON = 159 ± 51 min; GLU = 197 ± 46 min; FRU = 198 ± 67 min: P = 0.117). No differences were observed for any subjective measurements of appetite (P > 0.05) while blood glucose was elevated (P < 0.05) 20 min after ingestion on both GLU and FRU with this tending to be higher on GLU than FRU. FRU resulted in greater (P < 0.05) blood lactate concentrations than on the other trials. The results of this study demonstrate that gastric emptying rate of glucose and fructose is similar when ingested in a semi-solid meal. In addition, there is little difference in appetite response between these sugars, however, there are some differences in metabolic response which deserve further study.

The effect of brisk walking in the fasted versus fed state on metabolic responses, gastrointestinal function, and appetite in healthy men

ObjectiveTo investigate the effect of brisk walking in the fasted versus fed state on gastric emptying rate (GER), metabolic responses and appetite hormone responses.Subjects/methodsTwelve healthy men completed two 45 min treadmill walks, fasted (FASTED) and followed consumption of a standardised breakfast (FED). GER of a standardised lunch was subsequently measured for 2 h using the 13C-breath test method. Blood samples were collected at baseline, post-breakfast period, pre-exercise, immediately post exercise, pre-lunch then every 30 min following lunch for 2 h. Circulating concentrations of acylated ghrelin (GHR), glucagon-like peptide-1 (GLP-1), peptide tyrosine tyrosine (PYY), pancreatic polypeptide (PP), glucose, insulin, triglycerides, non-esterified fatty acids (NEFA) and cholesterol were measured. Subjective feelings of appetite were assessed at 15 min intervals throughout. Substrate utilisation was measured every 30 min, and continuously throughout exercise by indirect calorimetry.ResultsNo differences were observed for GER T½ (FASTED 89 ± 22 vs. FED 89 ± 24 min, P = 0.868) nor Tlag (FASTED 55 ± 15 vs. FED 54 ± 14 min, P = 0.704). NEFA concentrations were higher in FASTED at pre-exercise, post exercise and 30 min post exercise (pre-lunch) (all P < 0.05) but no differences were observed for glucose, cholesterol or triglycerides. Carbohydrate oxidation was greater at all time-points during FED exercise (all P < 0.05). Minimal changes in appetite were observed post lunch ingestion with no differences in PYY or GHR observed between trials. GLP-1 concentrations were greater in FED post-breakfast and pre-exercise (P < 0.05), though no differences were observed after lunch. A greater concentration of PP was observed in FED from pre-exercise to 30 min post lunch consumption (all P < 0.05). Insulin concentrations were higher in FED pre-exercise but higher in FASTED 1.5 h post lunch (P < 0.05).ConclusionThese findings suggest that gastrointestinal function, hunger and appetite regulatory hormones are not sensitive to low-intensity bouts of physical activity and holds positive implications for weight management practices.

Subjective feelings of appetite of wholegrain breakfasts evaluated under controlled, laboratory and 'at home' conditions.

Appetite regulating properties of foods are usually investigated under laboratory conditions, whereas in real life, foods are consumed under at home conditions. The objective of this study was to compare the acute effects of breakfasts when tested in a laboratory condition and in an at home condition. Appetite regulating properties of two bread breakfasts and two cereal breakfasts were also compared. In this randomized cross-over trial balanced for laboratory and at home test conditions, thirty-two women consumed five breakfasts, i.e. two bread breakfasts, two cereal breakfasts and one fried-egg breakfast. Visual analogue scales for measuring appetite were captured via an on-line scoring system and were analyzed as incremental area under the curve, as satiation phase and as satiety phase. Location effects were limited to two small effects only. An overall location effect in hunger feelings was observed (p = 0.040), which occurred specifically during the short satiation period (p = 0.0002) where hunger feelings scored higher under laboratory conditions. Similarly, a location effect was observed for desire to eat (p = 0.001); this was again higher under laboratory conditions. No other location effects were observed. Bread breakfasts did not differ in their appetite regulating properties. The Steel Cut oatmeal breakfast was reported to be more satiating (p = 0.001) as compared to the ready-to-eat cereal. Whereas the five breakfasts varied somewhat in their appetite regulating properties, evaluation under laboratory conditions overall did not result in different appetite scores compared to the at home conditions. This suggests that at home testing may be a useful alternative to laboratory test conditions for nutrition research.

Differences in the Postprandial Release of Appetite-Related Hormones Between Active and Inactive Men.

Active, as opposed to inactive, individuals are able to adjust their energy intake after preloads of different energy contents. The mechanisms responsible for this remain unknown. This study examined differences in plasma concentration of appetite-related hormones in response to breakfasts of different energy contents, between active and inactive men. Sixteen healthy nonobese (body mass index = 18.5-27kg/m2) adult males (nine active and seven inactive) participated in this study. Participants were given a high-energy (570kcal) or a low-energy (205kcal) breakfast in a random order. Subjective feelings of appetite and plasma concentrations of active ghrelin, active glucagon-like peptide-1, total peptide YY (PYY), cholecystokinin, and insulin were measured in fasting and every 30min up to 2.5hr, in response to both breakfasts. Mixed analysis of variance (fat mass [in percentage] as a covariate) revealed a higher concentration of active ghrelin and lower concentration of glucagon-like peptide-1, and cholecystokinin after the low-energy breakfast (p < .001 for all). Postprandial concentration of PYY was greater after the high energy compared with the low energy, but for inactive participants only (p = .014). Active participants had lower postprandial concentrations of insulin than inactive participants (p < .001). Differences in postprandial insulin between breakfasts were significantly lower in active compared with inactive participants (p < .001). Physical activity seems to modulate the postprandial plasma concentration of insulin and PYY after the intake of breakfasts of different energy contents, and that may contribute, at least partially, to the differences in short-term appetite control between active and inactive individuals.

Effects of cereal bar containing polydextrose on subjective feelings of appetite and energy intake in overweight adults over 15 d

The effects of 15 d polydextrose (16.7 g) consumption on energy intake (EI) and appetite feelings were investigated. Overweight adults consumed a polydextrose-bar or a control-bar matched in energy content as a midmorning snack for 15 consecutive days in a single-blind, randomised, crossover design. The two 15-d intervention periods were separated by a 15-d washout period. On the day 1 and the day 15 of each intervention period, energy intake (primary outcome) and appetite feelings (secondary outcome) were assessed. There were not significant main effects of the day, type of bar, or their interaction for EI (at lunchtime test meal, at rest of the day, or at total daily) or subjective feelings (hunger, desire to eat, fullness, and prospective food consumption) during the satiation and satiety periods. The results showed the consumption of polydextrose-bar during 15 d did not significantly affect energy intake and subjective feelings of appetite in overweight adults.

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.

High-Intensity Interval Training, Appetite, and Reward Value of Food in the Obese.

Studies on the effect of chronic interval training on appetite in the obese population are scarce. The aim of this study was to determine the effect of 12 wk of isocaloric programs of moderate-intensity continuous training (MICT), high-intensity interval training (HIIT), or short-duration HIIT on subjective feelings of appetite, appetite-related hormones, and reward value of food in sedentary obese individuals. Forty-six sedentary obese individuals (30 women and 16 men), with a body mass index of 33.3 ± 2.9 kg·m and age of 34.4 ± 8.8 yr, were randomly assigned to one of the three training groups: MICT (n = 14), HIIT (n = 16), or short-duration HIIT (n = 16). Exercise was performed three times per week for 12 wk. Subjective feelings of appetite and plasma levels of acylated ghrelin, polypeptide YY3-36, and glucagon-like peptide 1 were measured before and after a standard breakfast (every 30 min up to 3 h), before and after the exercise intervention. Fat and sweet taste preferences and food reward were measured using the Leeds Food Preference Questionnaire. A significant increase in fasting and postprandial feelings of hunger was observed with the exercise intervention (P = 0.01 and P = 0.048, respectively), but no effect of group and no interaction. No significant effect of exercise intervention, group, or interaction was found on fasting or postprandial subjective feelings of fullness, desire to eat, and prospective food consumption or plasma concentration of acylated ghrelin, polypeptide YY3-36, and glucagon-like peptide 1. No changes in food preference or reward over time, differences between groups, or interactions were found. This study suggests that chronic HIIT has no independent effect on appetite or food reward when compared with an isocaloric program of MICT in obese individuals.

Timeline of changes in appetite during weight loss with a ketogenic diet

Background/objective:Diet-induced weight loss (WL) leads to increased hunger and reduced fullness feelings, increased ghrelin and reduced satiety peptides concentration (glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK) and peptide YY (PYY)). Ketogenic diets seem to minimise or supress some of these responses. The aim of this study was to determine the timeline over which changes in appetite occur during progressive WL with a ketogenic very-low-energy diet (VLED).Subjects/methods:Thirty-one sedentary adults (18 men), with obesity (body mass index: 37±4.5 kg m−2) underwent 8 weeks (wks) of a VLED followed by 4 wks of weight maintenance. Body weight and composition, subjective feelings of appetite and appetite-related hormones (insulin, active ghrelin (AG), active GLP-1, total PYY and CCK) were measured in fasting and postprandially, at baseline, on day 3 of the diet, 5 and 10% WL, and at wks 9 and 13. Data are shown as mean±s.d.Results:A significant increase in fasting hunger was observed by day 3 (2±1% WL), (P<0.01), 5% WL (12±8 days) (P<0.05) and wk 13 (17±2% WL) (P<0.05). Increased desire to eat was observed by day 3 (P<0.01) and 5% WL (P<0.05). Postprandial prospective food consumption was significantly reduced at wk 9 (16±2% WL) (P<0.01). Basal total PYY was significantly reduced at 10% WL (32±8 days) (P<0.05). Postprandial active GLP-1 was increased at 5% WL (P<0.01) and CCK reduced at 5 and 10% WL (P<0.01, for both) and wk 9 (P<0.001). Basal and postprandial AG were significantly increased at wk 13 (P<0.001, both).Conclusions:WL with a ketogenic VLED transiently increases the drive to eat up to 3 weeks (5% WL). After that, and while participants are ketotic, a 10–17% WL is not associated with increased appetite. However, hunger feelings and AG concentrations increase significantly from baseline, once refeeding occurs.