The relationship between appetite scores and subsequent energy intake: An analysis based on 23 randomized controlled studies

IMPROVE 2022 International Meeting on Pathway-Related Obesity: Vision of Excellence

Nearly 90 clinicians and researchers from around the world attended the first IMPROVE 2022 International Meeting on Pathway-Related Obesity. Delegates attended in person or online from across Europe, Argentina and Israel to hear the latest scientific and clinical developments in hyperphagia and severe, early-onset obesity, and set out a vision of excellence for the future for improving the diagnosis, treatment, and care of patients with melanocortin-4 receptor (MC4R) pathway-related obesity. The meeting co-chair Peter Kühnen, Charité Universitätsmedizin Berlin, Germany, indicated that change was needed with the rapidly increasing prevalence of obesity and the associated complications to improve the understanding of the underlying mechanisms and acknowledge that monogenic forms of obesity can play an important role, providing insights that can be applied to a wider group of patients with obesity. World-leading experts presented the latest research and led discussions on the underlying science of obesity, diagnosis (including clinical and genetic approaches such as the role of defective MC4R signalling), and emerging clinical data and research with targeted pharmacological approaches. The aim of the meeting was to agree on the questions that needed to be addressed in future research and to ensure that optimised diagnostic work-up was used with new genetic testing tools becoming available. This should aid the planning of new evidence-based treatment strategies for the future, as explained by co-chair Martin Wabitsch, Ulm University Medical Center, Germany.

Augmented gut hormone response to feeding in older adults exhibiting low appetite

Age-related changes in gut hormones may play a role in anorexia of ageing. The aim of this study was to determine concentrations of ghrelin, PYY, and GLP-1 in older adults exhibiting an anorexia of ageing phenotype. Thirteen older adults with healthy appetite (OA-HA; 8f, 75±7 years, 26.0±3.2 kg·m-2), fifteen older adults with low appetite (OA-LA; 10f, 72±7 years, 23.6±3.1 kg·m-2), and twelve young adults (YA; 6f, 22±2 years, 24.4±2.0 kg·m-2) completed the study. Healthy appetite and low appetite were determined based on BMI, habitual energy intake, self-reported appetite, and laboratory-assessed ad libitum lunch intake. Participants provided a fasted measure of subjective appetite and blood sample (0 minutes) before consuming a standardised breakfast (450 kcal). Appetite was measured and blood samples were drawn throughout a 240-minute rest period. At 240 minutes, an ad libitum lunch meal was consumed. Relative intake at lunch (expressed as percentage of estimated total energy requirement) was lower for OA-LA (19.8±7.7%) than YA (41.5±9.2%, p<0.001) and OA-HA (37.3±10.0%, p<0.001). Ghrelin suppression was greater for OA-LA (net AUC, -78719±74788 pg·mL-1·240min-1) than both YA (-23899±27733 pg·mL-1·240min-1, p=0.016) and OA-HA (-21144±31161 pg·mL-1·240min-1, p=0.009). There were trends for higher GLP-1 concentrations in OA-LA compared with YA at 90 minutes (8.85±10.4 pM vs. 1.88±4.63 pM, p=0.073) and 180 minutes (5.00±4.71 pM vs. 1.07±2.83 pM, p=0.065). There was a trend for a greater PYY response for OA-LA compared with OA-HA (net AUC p=0.062). "Anorexigenic response score" - a composite score of gut hormone responses to feeding - showed greater anorexigenic response in OA-LA, compared with YA and OA-HA. No differences were seen in subjective appetite. These observations suggest augmented anorexigenic responses of gut hormones to feeding may be causal mechanisms of anorexia of ageing.

Post-exercise dietary macronutrient composition modulates components of energy balance in young, physically active adults

The effectiveness of exercise to reduce body mass is typically modest, partially due to energy compensation responses which may be linked to energy substrate availability around exercise. The present study aimed to investigate the effect of manipulating post-exercise energy substrate availability (high carbohydrate/low fat [HCLF] or low carbohydrate/high fat [LCHF] energy replacement) on energy balance components in the short-term (i.e., appetite, energy intake (EI) and energy expenditure (EE)).

METHODS

Appetite, EI, activity- and total- EE were measured in twelve healthy, young (21.0 ± 2.3 years) physically active participants (10 men, 2 women) on two occasions across 4 days after a 75-min run and an isocaloric energy replacement drink (HCLF and LCHF). Appetite was measured daily by visual analogue scales, EI was calculated by subtracting the energy content of food leftovers from a provided food package, activity- and total- EE determined by heart-rate accelerometery.

RESULTS

Composite appetite ratings between days were lower in HCLF (62.4 ± 12) compared to LCHF (68.3 ± 8.9 mm; p = 0.048). No differences between conditions were detected for EI. Cumulative activity-EE (HCLF=  20.9 ± 3.7, LCHF=  16.9 ± 3.1 MJ; p = 0.037), but not total-EE (HCLF=  44.6 ± 7.7, LCHF=  39.9 ± 4.7 MJ; p = 0.060), was higher for the HCLF condition than the LCHF across the measurement period.

CONCLUSION

Compared with low carbohydrate/high fat, immediate post-exercise energy replacement with a high carbohydrate/low fat drink resulted in higher short-term activity energy expenditure and lower appetite ratings.

Evaluation of Subjective Appetite Assessment under Free-Living vs. Controlled Conditions: A Randomized Crossover Trial Comparing Whole-Grain Rye and Refined Wheat Diets (VASA-Home)

BACKGROUND

Accurate assessment of self-reported appetite under free-living conditions is warranted to conduct large-scale intervention studies measuring appetite at a feasible cost. However, the performance of visual analogue scales (VASs) for this purpose has not been widely examined.

METHOD

This randomized crossover trial was conducted to evaluate VASs in free-living vs. clinic-based settings and to assess appetite response following hypocaloric whole-grain rye and refined wheat diets. Twenty-nine healthy adults with overweight or obesity continuously answered VAS questions about their perceived appetite from morning to evening.

RESULTS

No differences in whole-day VAS scores (primary outcome) between clinic-based and free-living settings were observed, whereas measures of total area under the curve (tAUC) showed increased fullness in clinic-based interventions of 7% (p < 0.008) for whole-day responses and 13% (p < 0.03) following a snack. Appetite responses for a whole day did not differ between diets whereas rye-based dinners induced 12% (p < 0.016) higher fullness and reduced hunger by 17% (p < 0.02) irrespective of setting. A reduction in hunger of 15% (p < 0.05) was also observed following rye-based vs. wheat-based lunches.

CONCLUSION

The results suggest that the VAS is valid for evaluation of appetite responses between diets under free-living conditions. No difference in self-reported appetite over the whole day was found after whole-grain rye vs. refined wheat-based diets, but there were some suggested differences at certain postprandial periods, in individuals with overweight or obesity.

Is the effect of menu energy labelling on consumer behaviour equitable? A pooled analysis of twelve randomized control experiments

Menu energy labelling has been implemented as a public health policy to promote healthier dietary choices and reduce obesity. However, it is unclear whether the influence energy labelling has on consumer behaviour differs based on individuals' demographics or characteristics and may therefore produce inequalities in diet. Data were analysed from 12 randomized control trials (N = 8508) evaluating the effect of food and drink energy labelling (vs. labelling absent) on total energy content of food and drink selections (predominantly hypothetical) in European and US adults. Analyses examined the moderating effects of participant age, sex, ethnicity/race, education, household income, body mass index, dieting status, food choice motives and current hunger on total energy content of selections. Energy labelling was associated with a small reduction (f2 = 0.004, -50 kcal, p < 0.001) in total energy selected compared to the absence of energy labelling. Participants who were female, younger, white, university educated, of a higher income status, dieting, motivated by health and weight control when making food choices, and less hungry, tended to select menu items of lower energy content. However, there was no evidence that the effect of energy labelling on the amount of energy selected was moderated by any of the participants' demographics or characteristics. Energy labelling was associated with a small reduction in energy content of food selections and this effect was similar across a range of participants' demographics and characteristics. These preliminary findings suggest that energy labelling policies may not widen existing inequalities in diet.

The effect of gastrointestinal bitter sensing on appetite regulation and energy intake: A systematic review

Taste receptors are located on the epithelial surface throughout the alimentary canal to identify nutrients and potential toxins. In the oral cavity, the role of taste is to encourage or discourage ingestion, while in the gastrointestinal (GI) tract, the taste receptors help the body prepare for an appropriate response to the ingested foods. The GI sensing of bitter compounds may alter the secretion of appetite-related hormones thereby reducing food intake, which may have potential use for managing health outcomes. This systematic literature review investigated the acute effects of administering different bitter tasting compounds on circulating levels of selected GI hormones, subjective appetite, and energy intake in humans. A literature search was conducted using Medline, CINAHL and Web of Science databases. Of 290 articles identified, 16 met the inclusion criteria. Twelve studies assessed food intake; four of these found bitter administration decreased food intake and eight did not. Fourteen studies assessed subjective appetite; seven found bitter administration affected at least one measure of appetite and seven detected no significant changes. Nine studies included measures of GI hormones; no significant effects were found for changes in GLP-1, CCK or PYY. Four studies measured motilin and ghrelin and found mostly consistent changes in either food intake or subjective appetite. Overall, the data on food intake and subjective appetite were inconsistent, with only motilin and ghrelin responsive to post-oral bitter administration. There is limited consistent conclusive evidence that bitter compounds influence food intake, appetite or hormones with the reasons for this discussed within. SYSTEMATIC REVIEW REGISTRATION: CRD42021226102.

Effects of whole-grain barley and oat β-glucans on postprandial glycemia and appetite: a randomized controlled crossover trial

This study aimed to determine the postprandial effects of barley bread (BB) and oat bread (OB), grain sources of β-glucans, on glycaemia and appetite by comparison with white bread (WB) and whole-wheat bread (WWB). This randomized controlled crossover trial included 20 healthy individuals (10 males and 10 females) who consumed WB, WWB, BB, and OB with a standard breakfast followed by an ad libitum lunch. Postprandial glucose and appetite responses were quantified as the incremental area under the curve (iAUC). Although the iAUC for glycaemic response was lower by 23.7%, 29.9%, and 27.9% after the consumption of BB, OB, and WWB compared with WB (p = 0.023), no differences were observed between BB, OB, and WWB (p > 0.05). BB had a lower iAUC for appetite sensation by 21.5%, 23.9%, and 55.7% compared with WB, WWB, and OB (p = 0.005). OB had no effect on appetite and was also less palatable than BB. Subsequent food intakes were similar after the consumption of all test breads (p > 0.05). The encouragement of healthier bread formulations that can beneficially modulate postprandial glycemia and appetite may contribute to the promotion of public health. This trial was registered at ClinicalTrials.gov as NCT04749498.

Associations between high-metabolic rate organ masses and fasting hunger: A study using whole-body magnetic resonance imaging in healthy males

BACKGROUND

Fat-free mass (FFM) has been shown to be positively associated with hunger and energy intake, an association mediated by resting metabolic rate (RMR). However, FFM comprises a heterogeneous group of tissues with distinct metabolic rates, and it remains unknown how specific high-metabolic rate organs contribute to the degree of perceived hunger.

OBJECTIVE

To examine whether FFM and its anatomical components were associated with fasting hunger when assessed at the tissue-organ level.

DESIGN

Body composition (quantitative magnetic resonance and magnetic resonance imaging), RMR and whole-body glucose oxidation (indirect calorimetry), HOMA-index as a marker of insulin sensitivity, nitrogen balance and fasting hunger (visual analogue scales) were assessed in 21 healthy males (age = 25 ± 3y; BMI = 23.4 ± 2.1 kg/m²) after 3 days of controlled energy balance.

RESULTS

FFM (r_s = 0.39; p = 0.09), RMR (r_s = 0.52; p = 0.02) and skeletal muscle mass (r_s = 0.57; p = 0.04), but not fat mass (r_s = -0.01; p = 0.99), were positively associated with fasting hunger. The association between the combined mass of high-metabolic rate organs (i.e., brain, liver, kidneys and heart; r_s = 0.58; p = 0.006) and fasting hunger was stronger than with FFM as a uniform body component. The strongest individual association was between liver mass and fasting hunger (r_s = 0.51; p = 0.02). No associations were observed between glucose parameters, markers of insulin sensitivity and fasting hunger. The encephalic measure, an index of brain-to-body energy allocation, was negatively associated with fasting hunger (r_s = -0.51; p = 0.02).

CONCLUSIONS

Fasting hunger was more strongly associated with the combined mass of high-metabolic rate organs than with FFM as a uniform body component, highlighting the importance of integrating individual tissue-organ masses and their functional correlates into homeostatic models of human appetite. The association between liver mass and fasting hunger may reflect its role in ensuring the brain's basal energy needs are met.

An extract of hops (Humulus lupulus L.) modulates gut peptide hormone secretion and reduces energy intake in healthy-weight men: a randomized, crossover clinical trial

BACKGROUND

Gastrointestinal enteroendocrine cells express chemosensory bitter taste receptors that may play an important role in regulating energy intake (EI) and gut function.

OBJECTIVES

To determine the effect of a bitter hop extract (Humulus lupulus L.) on acute EI, appetite, and hormonal responses.

METHODS

Nineteen healthy-weight men completed a randomized 3-treatment, double-blind, crossover study with a 1-wk washout between treatments. Treatments comprised either placebo or 500 mg of hop extract administered in delayed-release capsules (duodenal) at 11:00 h or quick-release capsules (gastric) at 11:30 h. Ad libitum EI was recorded at the lunch (12:00 h) and afternoon snack (14:00 h), with blood samples taken and subjective ratings of appetite, gastrointestinal (GI) discomfort, vitality, meal palatability, and mood assessed throughout the day.

RESULTS

Total ad libitum EI was reduced following both the gastric (4473 kJ; 95% CI: 3811, 5134; P = 0.006) and duodenal (4439 kJ; 95% CI: 3777, 5102; P = 0.004) hop treatments compared with the placebo (5383 kJ; 95% CI: 4722, 6045). Gastric and duodenal treatments stimulated prelunch ghrelin secretion and postprandial cholecystokinin, glucagon-like peptide 1, and peptide YY responses compared with placebo. In contrast, postprandial insulin, glucose-dependent insulinotropic peptide, and pancreatic polypeptide responses were reduced in gastric and duodenal treatments without affecting glycemia. In addition, gastric and duodenal treatments produced small but significant increases in subjective measures of GI discomfort (e.g., nausea, bloating, abdominal discomfort) with mild to severe adverse GI symptoms reported in the gastric treatment only. However, no significant treatment effects were observed for any subjective measures of appetite or meal palatability.

CONCLUSIONS

Both gastric and duodenal delivery of a hop extract modulates the release of hormones involved in appetite and glycemic regulation, providing a potential "bitter brake" on EI in healthy-weight men.

Predictors of Post-Exercise Energy Intake in Adolescents Ranging in Weight Status from Overweight to Severe Obesity

Exercise may sensitize individuals with overweight and obesity to appetitive signals (e.g., hunger and fullness cues), overriding trait eating behaviors that contribute to overeating and obesity, such as uncontrolled eating. The objective of the current study was to measure predictors of objective ad libitum energy intake at a laboratory-based, post-exercise test-meal in adolescents ranging in weight status from overweight to severe obesity. We hypothesized that appetitive states, rather than appetitive traits, would be the strongest predictors of energy intake at a post-exercise test-meal, after controlling for body size. At Baseline, 30 adolescents (ages 10-16 years, 50% female (F), 43% non-Hispanic white (NHW), 83% with obesity (OB)) completed state and trait appetite measures and an ad libitum dinner meal following intensive exercise. Nineteen of those participants (47% F, 32% NHW, 79% OB) completed identical assessments two years later (Year 2). Energy intake (kcal) at each time point was adjusted for fat-free mass index (i.e., body size). Adjusted energy intake was reliable from Baseline to Year 2 (ICC = 0.84). Multiple pre-meal appetite ratings were associated with test-meal energy intake. In stepwise linear regression models, pre-meal prospective food consumption was the strongest and only significant predictor of test-meal energy intake at both Baseline (R2 = 0.25, p = 0.005) and Year 2 (R2 = 0.41, p = 0.003). Baseline post-exercise energy intake was associated with weight change over two years (R2 = 0.24, p = 0.04), but not with change in fat mass (p = 0.11). Appetitive traits were not associated with weight or body composition change (p > 0.22). State appetite cues were the strongest predictors of post-exercise energy intake, independent of body size. Future studies should examine whether long-term exercise programs enhance responsiveness to homeostatic appetite signals in youth with overweight and obesity, with a goal to reduce excess energy intake and risk for weight gain over time.

Two-Month administration of Methylphenidate improves olfactory sensitivity and suppresses appetite in individuals with obesity

INTRODUCTION

Olfaction contributes to feeding behaviour and is modulated by changes in dopamine levels. Methylphenidate (MPH) increases brain dopamine levels and has been shown to reduce appetite and promote weight loss in patients with attention deficit hyperactivity disorder. The objectives of this study were to test the effect of MPH on olfaction, appetite, energy intake and body weight on individuals with obesity.

METHODS

In a randomized, double-blind study, 12 participants (age 28.9±6.7 yrs) (BMI 36.1±4.5 kg/m2) were assigned to MPH (0.5mg/kg) (n=5) or Placebo (n=7) twice daily for 2 months. Appetite (Visual Analog Scale), odour threshold (Sniffin' Sticks®), energy intake (food menu), and body weight (DEXA scan) were measured at day 1 and day 60.

RESULTS

MPH intake significantly increased odour threshold scores (6.3±1.4 vs. 9.4±2.1 and 7.9±2.3 vs. 7.8±1.9, respectively; p=0.029) vs. Placebo. There was a significantly greater suppression of appetite sensations (desire to eat (p=0.001), hunger (p=0.008), and prospective food consumption (p=0.003)) and an increase in fullness (p=0.028) over time in the MPH vs. Placebo.

CONCLUSIONS

MPH suppressed appetite and improved olfactory sensitivity in individuals with obesity. These data provide novel findings on the favourable effects of MPH on appetite and weight regulation in individuals living with obesity.

Development and validation of the Reasons Individuals Stop Eating Questionnaire (RISE-Q): A novel tool to characterize satiation

A variety of factors can influence satiation, and individual differences in reasons for meal termination may help to explain variability in food intake and susceptibility to overconsumption. We developed and validated a questionnaire to characterize the Reasons Individuals Stop Eating (RISE-Q). The initial RISE-Q was created by reviewing the published literature and identifying 47 reasons why individuals might stop eating. The RISE-Q asks respondents to rate how often each reason influences why they stop eating at a typical dinner meal by using a seven-point scale. Adults (N = 477, 77% women) from a participant database completed a survey online that included the initial RISE-Q and the satiation-related Satiety Responsiveness and Food Responsiveness scales of the Adult Eating Behavior Questionnaire (AEBQ). Self-reported height and weight were collected to calculate body mass index (BMI). The survey also assessed self-reported typical meal size. After factor analysis, the RISE-Q retained 31 items and identified five distinct scales of reasons for stopping eating: Decreased Food Appeal (mean ± SD: 2.6 ± 0.05, Cronbach's α = 0.89), Physical Satisfaction (5.0 ± 0.04, α = 0.85), Planned Amount (4.4 ± 0.05, α = 0.82), Self-Consciousness (2.4 ± 0.05, α = 0.88), and Decreased Priority of Eating (2.3 ± 0.04, α = 0.69). Thus, the most frequently reported reasons for meal termination were related to Physical Satisfaction and Planned Amount. Each RISE-Q scale was significantly correlated with at least one of the satiation-related AEBQ scales, suggesting that the RISE-Q has construct validity. RISE-Q scales were also correlated with BMI and measures of typical meal size. The RISE-Q provides a novel tool to assess differences across individuals in reported reasons for eating cessation. The RISE-Q can aid in further understanding risk factors for overconsumption and has potential clinical utility in the design of targeted weight-management interventions.

A Questionnaire-Based Assessment of Hunger, Speed of Eating and Food Intake in Children with Obesity

PURPOSE

The aim of this study was to investigate the hypothesis that obesity in Israeli children is associated with chronically increased hunger and to examine for persistent abnormalities of satiation and between-meal satiety in these children.

SUBJECTS/METHODS

The parents of 200 children with obesity and 100 normal-weight children completed a questionnaire together with their child that rated hunger, food intake at main meal, and speed of eating. Time to hunger from the main meal was also recorded. Children with hunger ratings above 4 on a 7-point scale were considered to have persistent hunger. Food intake ratings at the main meal were used as an approximate indicator of satiation and time from main meal to feeling hunger as an approximate indicator of between-meal satiety.

RESULTS

There were marked differences between children with obesity and controls for hunger, food intake at main meal and speed of eating ratings (all p<0.001). The difference to time to hunger reached significance after adjusting for age and sex (p=0.048). 41% of the children with obesity had the highest rating for persistent hunger versus 5% of controls (p<0.001).

CONCLUSION

Persistent hunger, abnormal food intake at the main meal and rapid eating are common in children with obesity and are often of marked degree. These findings could have implications for understanding how pediatric obesity perpetuates itself and even worsens and its resistance to successful treatment over the long term.

Oral Processing, Satiation and Obesity: Overview and Hypotheses

Increasing the speed of eating or decreasing the amount of chewing of a test meal significantly decreases its satiation, increases concomitant caloric intake, and influences entero-endocrine secretion. Speed of eating is a strong risk factor for obesity and longitudinal studies suggest an etiological relationship. Individuals with obesity have an increase in bite size, less chewing per bite, decreased satiation, and greater food intake. Oral processing in terms of bite size and amount of chewing per gram of food is influenced by food texture and textural complexity. Soft foods increase bite size and decrease chewing per gram of food and meal duration compared to hard foods. An ultra-processed diet can lead to greater weight gain than a non-processed diet and a significant increase in eating rate. Many children with obesity are noted by their parents to have persistent hunger on a questionnaire and this is often extreme. Results of attempts to change eating behavior have been mixed in terms of producing long-term changes in eating behavior and body weight. It is hypothesized that there may be a unidirectional relationship between changes in oral processing, satiation and weight gain. However, the presence of persistent hunger can produce a vicious cycle that may exacerbate obesity and make treatment difficult. The increased energy density of foods as found particularly in ultra-processed foods also influences energy intake and obesity.

Early changes in appetite and energy expenditure are not associated to body weight and fat losses in pre-menopausal women living with overweight/obesity

BACKGROUND

The aim of the study was to investigate whether early changes (1-week) in energy balance-related measures would predict changes in body weight (BW) and fat losses in women living with overweight/obesity.

METHODS

BW, body composition (DXA), resting energy expenditure (REE)(indirect calorimetry), olfactory performance (Sniffin' Sticks), appetite and palatability (visual analogue scale) were measured at baseline, after a 1-week of caloric restriction as well as post-intervention (at 10 and 20 weeks) in a group of 30 women living with overweight/obesity.

RESULTS

A significant decrease in REE (p = 0.033) was noted after 1 week. Fasting desire to eat (p = 0.004), hunger (p = 0.001) and prospective food consumption (p = 0.001) all increased after 1 week. Similarly, significant increases in AUC SQ for desire to eat (p = 0.01), hunger (p = 0.005) and prospective food consumption (p = 0.001) were noted after 1 week. However, these early changes were not associated to final BW or FM losses at the end of the weight loss intervention.

CONCLUSION

Despite significant changes in REE and appetite soon after the onset of a BW loss intervention, these early changes do not seem to predict final BW or FM losses at the end of the program in women living with overweight/obesity.

Daily energy balance and eating behaviour during a 14-day cold weather expedition in Greenland

We assessed energy compensation, appetite, and reward value of foods during a 14-day military expedition in Greenland realized by 12 male French soldiers, during which energy compensation was optimized by providing them with easy-to-eat palatable foods in excess. Although daily energy expenditure (estimated by accelerometry) stayed relatively constant throughout the expedition (15 ± 9 MJ·day−1), energy intake (EI; estimated by self-reported diaries) was 17% higher during the D8–D14 period compared with the D1–D7 period, leading to a neutral energy balance (EB). Body fat mass (BFM) significantly decreased (–1.0 ± 0.7 kg, p < 0.001) but not body mass (BM). Neither hunger scores (assessed by visual analog scales) nor components of the reward value of food (explicit liking (EL) and food preference) were significantly altered. However, changes in EL at D10 were positively correlated with changes in BM (r = 0.600, p < 0.05) and BFM (r = 0.680, p < 0.05) and changes in hunger in the EI of the relevant period (r = 0.743, p < 0.01 for D1–D7, r = 0.652, p < 0.05 for D8–14). This study shows that the negative EB and BM loss can be attenuated by an appropriate food supply and that subjective components of eating behaviour, such as hunger and EL, may be useful to predict the magnitude of energy compensation.

Novelty Energy intake increases during of a 14-day expedition in the cold. Energy compensation was likely facilitated by providing participants with easy-to-eat palatable and familiar foods. Hunger scores and EL for energy-dense foods were associated with high EIs and low BM changes.

Effects of Acute Eccentric Exercise on Appetite-Related Hormones and Food Preferences in Men

Eccentric exercise has been suggested to improve muscle atrophy, muscle function, and insulin sensitivity. The aim of this study was to examine the effect of acute eccentric exercise on appetite-related hormones, food preferences, and food intake. Fourteen moderately active men were recruited to participate in this study (age 24.2 ± 5.5 years; BMI 23.4 ± 3.3 kg/m²; VO_2max 48.9 ± 3.1 ml/kg/min). Three different conditions were implemented; no exercise, flat running “inclination 0” and downhill running “inclination –12%.” Appetite-related hormones, subjective appetite sensations, food preference and reward, and ad libitum food intake were measured at pre-, immediately post-, and 24 h post exercise. There were no significant median changes in total ghrelin or pancreatic peptide concentrations between conditions. There were also no median differences in subjective appetite ratings or energy intake between conditions, but the median change in explicit liking of sweet versus savory foods differed significantly between pre-exercise and 24 h post exercise (p = .013). Post-hoc analysis observed a significant difference in the pre-exercise to 24 h post exercise change between front running and downhill running (p = .023), and indicated greater liking of savory foods over sweet foods in downhill running than front running. However, no further differences were seen between conditions for the remaining food preference parameters, suggesting there were no systematic trends in these data. In conclusion, there was no effect of front and downhill running on eating behavior as compared to a nonexercise control condition, but these data need to be replicated in a larger and more heterogeneous sample.

Very Low and Higher Carbohydrate Diets Promote Differential Appetite Responses in Adults with Type 2 Diabetes: A Randomized Trial

BACKGROUND

Effects of very low carbohydrate (VLC) diets on appetite response in individuals with type 2 diabetes remain unclear.

OBJECTIVE

A secondary analysis was conducted to determine appetite responses to an energy-restricted [30% of energy (%E) deficit] very low carbohydrate (VLC) diet compared with a higher carbohydrate (HC) diet in adults who were overweight or obese with type 2 diabetes.

METHODS

Forty-four men and 40 women (mean ± SD, age: 58.7 ± 6.6 y; weight: 100.4 ± 15.5 kg; BMI: 34.5 ± 4.1 kg/m2; glycated hemoglobin: 7.3 ± 1.0%; duration of diabetes: 6.7 ± 5.6 y) were randomly assigned to diets categorized as VLC [14%E carbohydrate (<50 g/d), 28%E protein, 58%E fat (<10%E saturated fat)], or energy-matched HC [53%E carbohydrate, 17%E protein, 30%E fat (<10%E saturated fat)] combined with progressive multicomponent exercise (60 min; 3 d/wk). Body weight, average weekly "daily fasting" and "daily overall" appetite perceptions (hunger, fullness, prospective consumption, and desire to eat-visual analog scales) were assessed at baseline and after 4 and 16 wk. Changes between diets over time were assessed using repeated measures ANOVA.

RESULTS

Significant decreases in body weight did not differ between groups (VLC: -11.0 ± 5.4 kg/16 wk compared with HC: -10.1 ± 4.3 kg/16 wk, P = 0.40). Compared with HC, VLC had greater decreases in "daily overall" ratings of fullness (P time × diet < 0.01), such that scores were higher in HC at Week 4 (VLC:48 ± 3 vs HC:56 ± 3 mm, P = 0.001) and 16 (VLC:51 ± 2 vs HC:57 ± 3 mm, P = 0.019). Compared with HC, VLC had greater increases in prospective consumption ratings (P time × diet = 0.03), such that scores were lower in HC at Week 4 (VLC:33 ± 2 vs HC:28 ± 2 mm, P = 0.008), but not at Week 16 (VLC:33 ± 2 vs HC 31 ± 2 mm, P = 0.289).

CONCLUSIONS

In the context of energy restriction, both HC and VLC energy-matched diets promoted comparable effects on fasting perceptions of appetite, but the HC diet resulted in greater "daily overall" fullness and reduced prospective consumption. Further research is required to evaluate the effects of ad libitum diets differing in amounts of carbohydrate on appetite response in populations with type 2 diabetes. This trial was registered at www.anzctr.org.au as ACTRN12612000369820.

Effects of a novel combination of orlistat and acarbose on tolerability, appetite, and glucose metabolism in persons with obesity

Objective

There is an unmet medical need for a safe and effective weight loss product with minimal systemic side‐effects. In this study, the effect of a novel modified‐release fixed‐dose combination of orlistat and acarbose (MR‐OA) was compared with conventional orlistat (CO) regarding tolerability, appetite and glucose metabolism.

Methods

Sixty‐seven men with obesity, aged 24 to 60 years with body mass indexes (BMIs) 33 to 40 kg m⁻² or BMIs 30 to 32 kg m⁻² and waist circumference above 102 cm were included. They were randomized to either three different doses of the test formulation MR‐OA (60 mg orlistat/20 mg acarbose, 90/30 and 120/40) or CO (Xenical, 120 mg orlistat) for a 2‐week study of daily treatment. The participants spent days 1 and 14 at the clinical research centre where they received standardized meals, had blood sampling and filled in questionnaires regarding tolerability and appetite after meals. In days 2 to 13, the participants were at home and continued to fill in the questionnaires daily.

Results

In the MR‐OA groups, reports of liquid and oily stools as well as faecal incontinence were fewer, whereas reports of gastric distension and flatulence were higher, compared with the CO group. More participants reported decreased hunger in the 90/30 and 120/40 MR‐OA, and postprandial plasma glucose concentration was reduced in all MR‐OA groups compared with CO.

Conclusions

This study shows that by using a modified‐release dosage form, orlistat and acarbose can be combined without compromising tolerability. Furthermore, MR‐OA shows promising effects regarding reduction of appetite and reduces postprandial glucose. Tolerability is coupled to compliance and thereby efficacy of a treatment; therefore, this novel combination MR‐OA could be an effective approach for weight loss treatment. A follow‐up study in a more diverse population and for a longer duration with weight loss as primary outcome variable is planned.

Issues in Measuring and Interpreting Human Appetite (Satiety/Satiation) and Its Contribution to Obesity

PURPOSE OF REVIEW

The goals of this paper are to report current research practices in investigations of human appetite control and to assess their relationships with emerging theoretical principles. Appetite is often distinguished by the separation of homeostatic and hedonic processes.

RECENT FINDINGS

This report assesses the validity of a homeostatic toolkit to measure subjectively perceived hunger and its relationship to the developing processes of satiation (control of meal size) and satiety (control of the post-eating period). The capacity of a procedure to measure the influence of hedonic processes on food intake is also evaluated. A major issue is the relationship between the pattern of eating behaviour (influenced by the underlying drive to eat and the inhibition induced by the act of eating itself) and the parallel underlying profile of hormonal and other metabolic biomarkers. Increasing recognition is being given to individual variability in the expression of appetite, and the fact that the use of the average (mean) response conceals important information about the nature of appetite control. There is a growing interest in the identification of satiety phenotypes that operate in parallel to metabolic phenotypes. Interestingly, energy expenditure (metabolic and behavioural) contributes to an energy balance framework for understanding energy intake (appetite).

Mood and appetite: Their relationship with discretionary and total daily energy intake

BACKGROUND

Negative affect is shown consistently to promote unhealthy food choices and dietary intake in laboratory studies. However, this relationship in naturalistic settings is less clear and previous research is limited by dietary assessment methodology and neglects to account for several important moderating variables. This observational study aimed to examine the association of negative affect and other psychological factors associated with eating behaviour simultaneously with discretionary energy intake and total energy intake, and whether these were moderated by emotional eating predisposition or age, sex and weight status.

METHODS

One hundred adults completed a four-day food diary, a concurrent end-of-day questionnaire that assessed daily affect and experience of appetite, and the Three Factor Eating Questionnaire to assess trait eating behaviour. Food diaries provided data on participants' daily intake of total energy and of "discretionary items" (specific energy-dense and nutrient poor foods and beverages as defined by the Australian Guide to Healthy Eating). Stepwise random effects models were used to estimate the association of end-of-day ratings, trait eating behaviour and personal factors, and their interactions, with discretionary and total energy intake.

RESULTS

Daily rated negative affect and appetite were significantly and positively associated with discretionary intake, such that a one unit increase in each scale was associated with eating 139 kJ/d [SE 61] and 194 kJ/d [SE 68] more discretionary energy, respectively. Negative affect and its interaction with emotional eating were consistently, positively associated with discretionary energy intake. This relationship was strongest in younger participants (β = -4.9 [SE 2.2], p < .05). There was no interaction with sex or weight status. Total energy intake was not associated with negative affect nor its interaction with emotional eating but was consistently associated with appetite.

CONCLUSION

When personal factors (age, sex, BMI), trait eating behaviours and daily rated negative affect and appetite are considered simultaneously, daily discretionary intake is associated most strongly with negative affect. Individuals, particularly young adults, may be more likely to overeat discretionary energy on days that negative affect is rated more highly. However, this may not necessarily translate into greater total energy intake which was most consistently associated with daily rated appetite.

Food Intake during School Lunch Is Better Explained by Objectively Measured Eating Behaviors than by Subjectively Rated Food Taste and Fullness: A Cross-Sectional Study

School lunches contribute significantly to students’ food intake (FI) and are important to their long-term health. Objective quantification of FI is needed in this context. The primary aim of this study was to investigate how much eating rate (g/min), number of food additions, number of spoonfuls, change in fullness, food taste, body mass index (BMI), and sex explain variations in school lunch FI. The secondary aim was to assess the reliability of repeated FI measures. One hundred and three (60 females) students (15–18 years old) were monitored while eating lunch in their normal school canteen environment, following their usual school schedules. A subgroup of students (n = 50) participated in a repeated lunch (~3 months later). Linear regression was used to explain variations in FI. The reliability of repeated FI measurements was assessed by change in mean, coefficient of variation (CV), and intraclass correlation (ICC). The regression model was significant and explained 76.6% of the variation in FI. Eating rate was the strongest explanatory variable, followed by spoonfuls, sex, food additions, food taste, BMI, and change in fullness. All explanatory variables were significant in the model except BMI and change in fullness. No systematic bias was observed in FI (−7.5 g (95% CI = −43.1–28 g)) while individual students changed their FI from −417 to +349 g in the repeated meal (CV 26.1% (95% CI = 21.4–33.5%), ICC 0.74 (95% CI = 0.58–0.84)). The results highlight the importance of objective eating behaviors for explaining FI in a school lunch setting. Furthermore, our methods show promise for large-scale quantification of objectively measured FI and eating behaviors in schools.

Systematic review of the evidence for sustained efficacy of dietary interventions for reducing appetite or energy intake

We assessed evidence for changes in efficacy of food-based interventions aimed at reducing appetite or energy intake (EI), and whether this could be used to provide guidance on trial design. A systematic search identified randomized controlled trials testing sustained efficacy of diets, foods, supplements or food ingredients on appetite and/or EI. Trials had to include sufficient exposure duration (≥3 days) with appetite and/or EI measured after both acute and repeated exposures. Twenty-six trials met the inclusion criteria and reported data allowing for assessment of the acute and chronic effects of interventions. Most (21/26) measured appetite outcomes and over half (14/26) had objective measures of EI. A significant acute effect of the intervention was retained in 10 of 12 trials for appetite outcomes, and six of nine studies for EI. Initial effects were most likely retained where these were more robust and studies adequately powered. Where the initial, acute effect was not statistically significant, a significant effect was later observed in only two of nine studies for appetite and none of five studies for EI. Maintenance of intervention effects on appetite or EI needs to be confirmed but seems likely where acute effects are robust and replicable in adequately powered studies.

Methodological and reporting quality in laboratory studies of human eating behavior

The methodological quality and reporting practices of laboratory studies of human eating behavior determine the validity and replicability of nutrition science. The aim of this research was to examine basic methodology and reporting practices in recent representative laboratory studies of human eating behavior. We examined laboratory studies of human eating behavior (N = 140 studies) published during 2016. Basic methodology (e.g., sample size, use of participant blinding) and reporting practices (e.g., information on participant characteristics) were assessed for each study. Some information relating to participant characteristics (e.g., age, gender) and study methodology (e.g., length of washout periods in within-subjects studies) were reported in the majority of studies. However, other aspects of study reporting, including participant eligibility criteria and how sample size was determined were frequently not reported. Studies often did not appear to standardize pre-test meal appetite or attempt to blind participants to study aims. The average sample size of studies was small (between-subjects design studies in particular) and the primary statistical analyses in a number of studies (24%) were reliant on very small sample sizes that would be likely to produce unreliable results. There are basic methodology and reporting practices in the laboratory study of human eating behavior that are sub-optimal and this is likely to be affecting the validity and replicability of research. Recommendations to address these issues are discussed.

Investigating predictors of eating: is resting metabolic rate really the strongest proxy of energy intake?

Background: Evidence suggests that fat-free mass and resting metabolic rate (RMR), but not fat mass, are strong predictors of energy intake (EI). However, body composition and RMR do not explain the entire variance in EI, suggesting that other factors may contribute to this variance.Objective: We aimed to investigate the associations between body mass index (in kg/m²), fat mass, fat-free mass, and RMR with acute (1 meal) and daily (24-h) EI and between fasting appetite ratings and certain eating behavior traits with daily EI. We also evaluated whether RMR is a predictor of the error variance in acute and daily EI.Design: Data collected during the control condition of 7 studies conducted in Ottawa, Ontario, Canada, were included in these analyses (n = 191 and 55 for acute and daily EI, respectively). These data include RMR (indirect calorimetry), body composition (dual-energy X-ray absorptiometry), fasting appetite ratings (visual analog scales), eating behavior traits (Three-Factor Eating Questionnaire), and EI (food buffet or menu).Results: Fat-free mass was the best predictor of acute EI (R² = 0.46; P < 0.0001). The combination of fasting prospective food consumption ratings and RMR was the best predictor of daily EI (R² = 0.44; P < 0.0001). RMR was a statistically significant positive predictor of the error variance for acute (R² = 0.20; P < 0.0001) and daily (R² = 0.23; P < 0.0001) EI. RMR did, however, remain a statistically significant predictor of acute (R² = 0.32; P < 0.0001) and daily (R² = 0.30; P < 0.0001) EI after controlling for this error variance.Conclusions: Our findings suggest that combined measurements of appetite ratings and RMR could be used to estimate EI in weight-stable individuals. However, greater error variance in acute and daily EI with increasing RMR values was observed. Future studies are needed to identify whether greater fluctuations in daily EI over time occur with increasing RMR values. This trial was registered at clinicaltrials.gov as NCT02653378.

The influence of ethnicity and glucose tolerance status on subjective hunger sensations and prospective food intake in overweight and obese Asian and European Australians

AIMS

To examine the influence of ethnicity and glucose tolerance status on subjective sensations and food intake in overweight/obese Asian and European Australians.

METHODS

18 Asians and 26 Europids were classified as normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) based on serial measures of finger-prick glucose following an oral glucose tolerance test (OGTT). Subjective sensations of hunger and satiety were measured before and every 15min after the OGTT using a visual analogue scale (VAS). Food intake was measured covertly from consumption of a buffet style lunch and from self-maintained 24h food records. All serial measurements were converted into total area under the curve (TAUC) and comparisons adjusted for age, fat and fat-free mass.

RESULTS

There was a significant difference interaction between ethnicity (ETH) and glucose tolerance (GTT) for subjective fullness, desire for food and prospective food intake. IGT Asians had significantly greater sensations of fullness, but lesser prospective food and desire to eat, as compared to other groups. However there were no differences in calorie and macronutrient intake at buffet lunch or over 24-h.

CONCLUSION

Interactions between ethnicity and glucose tolerance status in subjective sensations did not transcribe to differences in prospective food intake.

Consistency of Eating Rate, Oral Processing Behaviours and Energy Intake across Meals

Faster eating has been identified as a risk factor for obesity and the current study tested whether eating rate is consistent within an individual and linked to energy intake across multiple meals. Measures of ad libitum intake, eating rate, and oral processing at the same or similar test meal were recorded on four non-consecutive days for 146 participants (117 male, 29 female) recruited across four separate studies. All the meals were video recorded, and oral processing behaviours were derived through behavioural coding. Eating behaviours showed good to excellent consistency across the meals (intra-class correlation coefficients > 0.76, p < 0.001) and participants who ate faster took larger bites (β ≥ 0.39, p < 0.001) and consistently consumed more energy, independent of meal palatability, sex, body composition and reported appetite (β ≥ 0.17, p ≤ 0.025). Importantly, eating faster at one meal predicted faster eating and increased energy intake at subsequent meals (β > 0.20, p < 0.05). Faster eating is relatively consistent within individuals and is predictive of faster eating and increased energy intake at subsequent similar meals consumed in a laboratory context, independent of individual differences in body composition.

The bogus taste test: Validity as a measure of laboratory food intake

Because overconsumption of food contributes to ill health, understanding what affects how much people eat is of importance. The ‘bogus’ taste test is a measure widely used in eating behaviour research to identify factors that may have a causal effect on food intake. However, there has been no examination of the validity of the bogus taste test as a measure of food intake. We conducted a participant level analysis of 31 published laboratory studies that used the taste test to measure food intake. We assessed whether the taste test was sensitive to experimental manipulations hypothesized to increase or decrease food intake. We examined construct validity by testing whether participant sex, hunger and liking of taste test food were associated with the amount of food consumed in the taste test. In addition, we also examined whether BMI (body mass index), trait measures of dietary restraint and over-eating in response to palatable food cues were associated with food consumption. Results indicated that the taste test was sensitive to experimental manipulations hypothesized to increase or decrease food intake. Factors that were reliably associated with increased consumption during the taste test were being male, have a higher baseline hunger, liking of the taste test food and a greater tendency to overeat in response to palatable food cues, whereas trait dietary restraint and BMI were not. These results indicate that the bogus taste test is likely to be a valid measure of food intake and can be used to identify factors that have a causal effect on food intake.

Regulation of plasma agouti-related protein and its relationship with hunger in lean and obese men

Agouti-related protein (AgRP) is an orexigenic (appetite stimulating) neuropeptide suggested to exert tonic control over long-term energy balance. While some have speculated AgRP is not involved in the episodic (i.e. meal to meal energy intake) control, acute decreases in plasma agouti-related protein (AgRP) following a meal have been observed in humans in a role consistent with episodic control for AgRP. Whether changes in plasma AgRP are associated with episodic, and/or tonic changes in appetite has yet to be directly examined. The present study examined the relationship between agouti-related protein (AgRP), leptin and the regulation of appetite following a 48-h fast and an acute meal challenge. Blood samples were obtained from young lean and obese men before and after a 48 h fast (lean n = 10; obese n = 7). Fasting resulted in an increase in AgRP and a decrease in leptin with these changes being greater in lean than obese. In addition, blood samples were obtained from lean men before and 1, 2, 3 and 4 h after a meal (n = 8). Following a meal, AgRP was reduced from 2 to 4 h, a change that was dissociated from both leptin and subjective measures of hunger and satiety. These results demonstrate that AgRP is not associated with changes in hunger or satiety, and can change without corresponding changes in leptin. This suggests that AgRP may not be involved in the episodic control of appetite and the release of AgRP may involve signals other than leptin.

Energy depletion by diet or aerobic exercise alone: impact of energy deficit modality on appetite parameters

BACKGROUND

Millions of Americans attempt to lose weight each year, and it is unclear whether the modality of acute, tightly controlled energy depletions can differently affect appetite parameters and olfaction.

OBJECTIVE

The objectives were to examine how the modality of an acute 3-d isocaloric 25% energy depletion by dieting alone or by aerobic exercise alone differently affects appetite and appetite-related hormones, ad libitum feeding, food reward (snack points), and olfaction.

DESIGN

Ten male participants with a mean ± SD age of 23.7 ± 5.1 y and an initial mean ± SD body weight of 83.2 ± 11.5 kg participated in this randomized crossover design. Baseline measurement [day 1 of the control condition (CON1)] was performed and repeated 3 d later [day 4 of the control condition (CON4)], after which randomization was applied to the order of the 2 experimental conditions: 25% daily needs energy deficits induced by diet only (DIET) and by exercise only (EX) and tested before [day 1 of DIET (DIET1) and day 1 of EX (EX1)] and after 3 d [day 4 of DIET (DIET4) and day 4 of EX (EX4)] of the intervention. Body weight, leptin and ghrelin concentrations, relative-reinforcing value of food, and olfaction were measured at days 1 and 4. Body composition (dual-energy X-ray absorptiometry), ad libitum energy intake (EI; buffet), and palatability (visual analog scale) were measured only at day 4.

RESULTS

Relative to CON4, EI (P= 0.001), palatability (P= 0.01), and odor threshold (P= 0.05) were higher at DIET4; relative to CON4, palatability (P= 0.03) was higher at EX4. Compared with EX4, EI was higher for DIET4 (P= 0.006). Relative to CON4, snack points earned were higher at DIET4 (P= 0.03) and EX4 (P= 0.001); more snack points were earned at EX4 relative to DIET4 (P= 0.001).

CONCLUSIONS

Compared with the control condition, DIET represented a greater acute challenge to appetite regulation than EX, as demonstrated by greater appetite and ad libitum EI. This study confirms that compared with depletions by exercise alone, acute caloric restriction results in rapid changes in appetite that result in compensatory eating, which may initially dissuade potential success in weight-loss efforts. This trial was registered at clinicaltrials.gov as NCT02653378.

Visual exposure to large and small portion sizes and perceptions of portion size normality: Three experimental studies

Portion sizes of many foods have increased in recent times. In three studies we examined the effect that repeated visual exposure to larger versus smaller food portion sizes has on perceptions of what constitutes a normal-sized food portion and measures of portion size selection. In studies 1 and 2 participants were visually exposed to images of large or small portions of spaghetti bolognese, before making evaluations about an image of an intermediate sized portion of the same food. In study 3 participants were exposed to images of large or small portions of a snack food before selecting a portion size of snack food to consume. Across the three studies, visual exposure to larger as opposed to smaller portion sizes resulted in participants considering a normal portion of food to be larger than a reference intermediate sized portion. In studies 1 and 2 visual exposure to larger portion sizes also increased the size of self-reported ideal meal size. In study 3 visual exposure to larger portion sizes of a snack food did not affect how much of that food participants subsequently served themselves and ate. Visual exposure to larger portion sizes may adjust visual perceptions of what constitutes a 'normal' sized portion. However, we did not find evidence that visual exposure to larger portions altered snack food intake.

Effects of eating rate on satiety: A role for episodic memory?

Eating slowly is associated with a lower body mass index. However, the underlying mechanism is poorly understood. Here, our objective was to determine whether eating a meal at a slow rate improves episodic memory for the meal and promotes satiety. Participants (N=40) consumed a 400ml portion of tomato soup at either a fast (1.97ml/s) or a slow (0.50ml/s) rate. Appetite ratings were elicited at baseline and at the end of the meal (satiation). Satiety was assessed using; i) an ad libitum biscuit 'taste test' (3h after the meal) and ii) appetite ratings (collected 2h after the meal and after the ad libitum snack). Finally, to evaluate episodic memory for the meal, participants self-served the volume of soup that they believed they had consumed earlier (portion size memory) and completed a rating of memory 'vividness'. Participants who consumed the soup slowly reported a greater increase in fullness, both at the end of the meal and during the inter-meal interval. However, we found little effect of eating rate on subsequent ad libitum snack intake. Importantly, after 3h, participants who ate the soup slowly remembered eating a larger portion. These findings show that eating slowly promotes self-reported satiation and satiety. For the first time, they also suggest that eating rate influences portion size memory. However, eating slowly did not affect ratings of memory vividness and we found little evidence for a relationship between episodic memory and satiety. Therefore, we are unable to conclude that episodic memory mediates effects of eating rate on satiety.

Nutrients, satiety, and control of energy intake

In the context of the worldwide epidemic of obesity affecting men and women of all ages, it is important to understand the mechanisms that control human appetite, particularly those that allow the adjustment of energy intake to energy needs. Satiety is one important psycho-biological mechanism whose function is to inhibit intake following the ingestion of a food or a beverage. According to the classical theories of appetite control, satiety is influenced by macronutrient intake and/or metabolism. Satiety also seems to be modified by micronutrients, non-nutrients, and some bioactive food constituents. Under optimal conditions, satiety should be well connected with hunger and satiation in a way that spontaneously leads to a close match between energy intake and expenditures. However, the current obesity epidemic suggests that dysfunctions often affect satiety and energy intake. In this regard, this paper presents a conceptual integration that hopefully will help health professionals address satiety issues and provide the public with informed advice to facilitate appetite control.

Gender Differences in the Appetite Response to a Satiating Diet

We examined gender differences in appetite sensations when exposed to Mediterranean diet (MedDiet) meals and determined whether there are gender differences in the change in the satiating properties of the MedDiet over time. Thirty-eight men and 32 premenopausal women consumed a 4-week isoenergetic MedDiet under controlled conditions. Visual analogue scales were used to measure perceived appetite sensations before and immediately after each meal consumed over the course of one day (Wednesday) of the first and the fourth week of intervention. Women reported greater decreases for desire to eat, hunger, and appetite score than men in response to the consumption of the MedDiet meals (gender-by-meal interactions, resp., P = 0.04, P = 0.048, and P = 0.03). Fullness and prospective food consumption responses did not significantly differ between men and women. Between the first and the fourth week of intervention, premeal prospective food consumption increased with time in men (P = 0.0007) but not in women (P = 0.84; P for gender-by-time interaction = 0.04). These results indicate gender differences in appetite sensations when exposed to the MedDiet. These results may be useful in order to have a better understanding of gender issues for body weight management.