Hunger and satiety: a multidimensional assessment of responses to caloric loads

Validation of the adult eating behavior questionnaire in a Norwegian sample of adolescents

Eating behaviors are related to health and well-being. To examine stability and change in eating behaviors throughout life, developmentally appropriate measures capturing the same eating behavior dimensions are needed. The newly developed Adult Eating Behavior Questionnaire (AEBQ) builds on the well-established parent-reported Children's Eating Behavior Questionnaire (CEBQ), and together with the corresponding Baby Eating Behavior Questionnaire (BEBQ), these questionnaires cover all ages. However, validation studies on adolescents are relatively sparse and have yielded somewhat conflicting results. The present study adds to existing research by testing the psychometric properties of the AEBQ in a sample of 14-year-olds and examining its construct validity by means of the parent-reported CEBQ. The current study uses age 14 data (analysis sample: n = 636) from the ongoing Trondheim Early Secure Study, a longitudinal study of a representative birth cohort of Norwegian children (baseline: n = 1007). Confirmatory factor analysis (CFA) was conducted to test the factorial validity of AEBQ. Construct validity was examined by bivariate correlations between AEBQ subscales and CEBQ subscales. CFAs revealed that a 7-factor solution of the AEBQ, with the Hunger scale removed, was a better-fitting model than the original 8-factor structure. The 7-factor model was respecified based on theory and model fit indices, resulting in overall adequate model fit (χ2 = 896.86; CFI = 0.924; TLI = 0.912; RMSEA = 0.05 (90% CI: 0.043, 0.051); SRMR = 0.06). Furthermore, small-to-moderate correlations were found between corresponding AEBQ and CEBQ scales. This study supports a 7-factor solution of the AEBQ without the Hunger scale and provide evidence of its construct validity in adolescents. Several of the CEBQ subscales were significantly associated with weight status, whereas this was the case for only one of the AEBQ scales.

Apple versus chocolate: Evidence for discrimination of distension-related and calorie-related satiety signals in post-prandial fullness and hunger, and in the quality and location of other body sensations

Gastric distension and detection of macronutrients (calories) in the gut are determinants of satiation and satiety. We tested effects of these variables on body sensations after eating, and their connection with visual-analogue scale (VAS) hunger and fullness ratings. Participants completed VAS ratings and quality and location of body sensations tasks after consumption of milk chocolate (38 g, 200 kcal) versus fresh apple fruit matched for weight (38 g, 20 kcal) and matched for calories (380 g, 200 kcal). Effects of food weight (380 vs 38 g) were large and located predominantly in the abdominal region. They also occupied a greater body area and occurred sooner after eating than effects related to calories (200 vs 20 kcal). The same pattern was apparent in the results from the quality of sensations task. VAS ratings indicated that hunger was affected by food volume and calories, whereas fullness was affected primarily by food volume. Together, these results provide evidence of dissociation of the perceived after-effects of food ingestion related to food volume and food calorie content in humans. Additionally, the studies demonstrate the utility of two rarely used, semi-quantitative tasks, which generate information on the identity, intensity, valence, and location of eating-related sensations.

Concurrent Validity of the Adult Eating Behavior Questionnaire in a Canadian Sample

The current study aimed to test the factor structure of the Adult Eating Behavior Questionnaire (AEBQ), its construct validity against the Three-Factor Eating Questionnaire (TFEQ-R18) and its associations with body mass index (BMI) in Canadian adults (n = 534, 76% female). Confirmatory factor analysis (CFA) revealed that a seven-factor AEBQ model, with the Hunger subscale removed, had better fit statistics than the original eight-factor structure. Cronbach's alpha was used to assess the internal reliability of each subscale and resulted with α > 0.70 for all subscales except for Hunger (α = 0.68). Pearson's correlations were used to inform the convergent and discriminant validation of AEBQ against the TFEQ-R18 and to examine the relationship between AEBQ and BMI. All AEBQ Food Approach subscales positively correlated with that of the TFEQ-R18 Emotional Eating and Uncontrolled Eating subscales. Similarly, BMI correlated positively with Food Approach subscales (except Hunger) and negatively with Food Avoidance subscales (except Food Fussiness). These results support the use of a seven-factor AEBQ for adults self-reporting eating behaviors, construct validity of the AEBQ against TFEB-R18, and provide further evidence for the association of these traits with BMI.

Hungry people prefer larger bodies and objects: The importance of testing boundary effects

Several lab-based studies have indicated that when people are hungry, they judge larger women's bodies as more attractive, compared to when they are satiated. These satiety-dependent judgements are assumed to provide explanatory power when it comes to the noted cross-cultural differences in attitudes towards women's adiposity, whereby people who live in regions that are under greater nutritional stress tend to have more favourable attitudes towards bigger bodies. However, it is premature to assume that women's bodies are the proper or actual domain of the satiety-dependent judgement shifts found within research study testing contexts until stimuli other than female bodies have also been tested: The research programme falls into the trap of confirmation bias unless we also seek out disconfirmatory evidence and test the boundaries of the effects of hunger. Accordingly, we collected attractiveness judgements of female and male bodies manipulated to vary in size by varying level of adiposity, and objects manipulated to vary in size, from 186 participants who also reported their current hunger level. We found that larger sizes of stimuli in general, and women's bodies in particular, especially when judged by women, were judged as more attractive by the hungrier participants. We discuss these patterns in the context of the Insurance Hypothesis, the Environmental Security Hypothesis, and the impact of hunger on acquisition.

Appetitive traits and relationships with BMI in adults: Development of the Adult Eating Behaviour Questionnaire

The Child Eating Behaviour Questionnaire (CEBQ) is a validated parent-report measure of appetitive traits associated with weight in childhood. There is currently no matched measure for use in adults. The aim of this study was to adapt the CEBQ into a self-report Adult Eating Behaviour Questionnaire (AEBQ) to explore whether the associations between appetitive traits and BMI observed in children are present in adults. Two adult samples were recruited one year apart from an online survey panel in 2013 (n = 708) and 2014 (n = 954). Both samples completed the AEBQ and self-reported their weight and height. Principal component analysis (PCA) was used to derive 35 items for the AEBQ in Sample 1 and confirmatory factor analysis (CFA) was used to replicate the factor structure in Sample 2. Reliability of the AEBQ was assessed using Cronbach’s α and a two week test-retest in a sub-sample of 93 participants. Correlations between appetitive traits measured by the AEBQ and BMI were calculated. PCA and CFA results showed the AEBQ to be a reliable questionnaire (Cronbach’s α > 0.70) measuring 8 appetitive traits similar to the CEBQ [Hunger (H), Food Responsiveness (FR), Emotional Over-Eating (EOE), Enjoyment of Food (EF), Satiety Responsiveness (SR), Emotional Under-eating (EUE), Food Fussiness (FF) and Slowness in Eating (SE)]. Associations with BMI showed FR, EF (p < 0.05) and EOE (p < 0.01) were positively associated and SR, EUE and SE (p < 0.01) were negatively associated. Overall, the AEBQ appears to be a reliable measure of appetitive traits in adults which translates well from the validated child measure. Adults with a higher BMI had higher scores for ‘food approach’ traits (FR, EOE and EF) and lower scores for ‘food avoidance’ traits (SR, EUE and SE).

The nature of feelings: evolutionary and neurobiological origins

Feelings are mental experiences of body states. They signify physiological need (for example, hunger), tissue injury (for example, pain), optimal function (for example, well-being), threats to the organism (for example, fear or anger) or specific social interactions (for example, compassion, gratitude or love). Feelings constitute a crucial component of the mechanisms of life regulation, from simple to complex. Their neural substrates can be found at all levels of the nervous system, from individual neurons to subcortical nuclei and cortical regions.

'Expected satiety' changes hunger and fullness in the inter-meal interval

Previously, we have shown that foods differ markedly in the satiety that they are expected to confer (compared calorie-for-calorie). In the present study we tested the hypothesis that 'expected satiety' plays a causal role in the satiety that is experienced after a food has been consumed. Before lunch, participants (N=32) were shown the ingredients of a fruit smoothie. Half were shown a small portion of fruit and half were shown a large portion. Participants then assessed the expected satiety of the smoothie and provided appetite ratings, before, and for three hours after its consumption. As anticipated, expected satiety was significantly higher in the 'large portion' condition. Moreover, and consistent with our hypothesis, participants reported significantly less hunger and significantly greater fullness in the large-portion condition. Importantly, this effect endured throughout the test period (for three hours). Together, these findings confirm previous reports indicating that beliefs and expectations can have marked effects on satiety and they show that this effect can persist well into the inter-meal interval. Potential explanations are discussed, including the prospect that satiety is moderated by memories of expected satiety that are encoded around the time that a meal is consumed.

The actual, but not labelled, fat content of a soup preload alters short-term appetite in healthy men

The effects of the actual and labelled fat content of a soup preload on appetite at a test meal 30 min later were assessed in 16 healthy men. Each participant ate lunch on four occasions, combining two levels of fat energy (Low, 265 kJ or High, 1510 kJ) and two types of label (Low-fat or High-fat), presented as fictitious soup brand names. Preliminary work established that the Low-fat labels produced an expectation of reduced fat content and lower anticipated hedonic ratings, whereas the High-fat labels generated expectations of a high-fat content and above average hedonic ratings. These expectancies were confirmed in the main experiment, with the soups labelled as high fat rated as both more pleasant and creamy than those labelled low-fat, independent of actual fat content. However, intake at the test meal was unaffected by the preload label, but instead reflected the actual fat (hence, energy) content of the soup, with significantly lower food intake after the high-fat soup regardless of the food label. Rated hunger was lower, and fullness higher, at the start of the meal after the high-fat preloads regardless of how they were labelled, while the pattern of appetite change during the test meal was unaffected by preload. These results suggest that realistic food labels can modify the immediate experience of a consumed food, but do not alter appetite 30 min later in healthy men.

Effects of (-)-hydroxycitric acid on appetitive variables

(-)-Hydroxycitric acid (HCA) reportedly promotes weight loss, in part, through suppression of hunger. However, this mechanism has never been evaluated in humans in a controlled study. Eighty-nine mildly overweight females were prescribed 5020-kJ diets for 12 weeks as part of a double-blind, placebo-controlled parallel group study. Forty-two participants ingested 400-mg caplets of Garcinia cambogia 30-60 min prior to meals for a total dose of 2.4 g/day (1.2 g/day HCA). Forty-seven participants ingested matched placebos. Weight and body composition were assessed at baseline and every other week for 12 weeks. Food intake and appetitive variables were assessed at baseline and monthly for 12 weeks. Both groups lost body weight with the active group achieving a significantly greater reduction (3. 7+/-3.1 kg versus 2.4+/-2.9 kg). No effects of the HCA were observed on appetitive variables. The active treatment group did not exhibit better dietary compliance or significant correlations between appetitive variables and energy intake or weight change. This study does not support a satiety effect of HCA.

Effects of attentional focus on subjective hunger ratings

Food-deprived and non-deprived non-dieters rated their hunger and fullness during a <<<<free think>>>> period and then during three counterbalanced video presentations-a control video, a video featuring palatable food cues and an absorbing non-food video. The food-cue video increased hunger ratings for both deprived and non-deprived participants. The absorbing non-food video decreased hunger for deprived (but not for non-deprived) participants. Changes in fullness ratings were not simply the complement of changes in hunger ratings. The discussion focuses on the cognitive mediators of hunger perception.

Information about the fat content of preloads influences energy intake in healthy women

OBJECTIVE

This study tested the hypothesis that the perceived fat content of a preload (a required first course) influences subsequent food and energy intake.

SUBJECTS AND DESIGN

Forty-eight healthy, nondieting women (24 restrained, 24 unrestrained) were given a fixed amount (350 g) of three different yogurts (low-fat, low-calorie; low-fat, high-calorie; high-fat, high-calorie), or no yogurt, followed by lunch (30 minutes after the yogurt preload was served) and dinner (4.5 hours later). Each subject was tested in all four conditions in a counterbalanced design. Half of the subjects received accurate information, in the form of a label, about the fat content of the yogurts, which did not necessarily correspond to energy content; the other half received no information.

ANALYSES

Energy intake, the percentage of macronutrients in the meals, and subjective sensations of hunger and satiety were analyzed.

RESULTS

No effect of restraint was noted in the intake analyses. A significant information-by-preload interaction (P < .05) was found. Subjects who had information consumed more energy at lunch after eating a preload labeled low fat than after eating a preload with similar energy content but labeled high fat. The opposite response was seen in women who did not receive information. When energy consumed at dinner was included in the analyses, overall intake was still significantly greater in the women who received information and ate a low-fat preload. No differences were found in the percentage of macronutrients selected or in subjective sensations after consumption of any of the preloads.

CONCLUSIONS

Messages about the fat content of a food can influence energy intake in healthy women.

Gender, dietary restraint, and smoking's influence on hunger and the reinforcing value of food

Smoking may enhance satiety following meal consumption, thereby reducing subsequent eating (i.e., between-meal snacks), especially in women high in dietary restraint. Female smokers (n = 20, 10 high and 10 low restraint) and male smokers (n = 10) participated in two sessions, involving overnight abstinence from food and smoking (smoking abstinence day) or from food only (smoking day), in a within-subjects design. The reinforcing value of food was determined by the number of responses made to obtain food reinforcers (100-kcal snack portions) vs. money using a concurrent schedules computer task. Subjects were given a small caloric load on each day followed by access to food vs. money. On the smoking day, subjects were allowed to smoke every 30 min during the session as well as ad lib before the session. Self-reported hunger was also assessed upon arrival (after fasting) and following the caloric load during each session. Results indicated no effect of smoking on initial hunger rating, after fasting, but hunger ratings following the caloric load declined significantly more during smoking vs. abstinence days for all subjects, consistent with an enhancement of postmeal satiety due to smoking. There was no overall main effect of smoking on food-reinforced responding. However, responding for food was significantly less during the smoking vs. abstinence days for high-restraint females only and not for low-restraint females or for males. These findings indicate that smoking's acute influence on reducing food intake does not reflect a broad gender difference but may be specific to dietary restraint.

Effects of physical and chemical characteristics of food on specific and general satiety

Two high-energy-dense and two low-energy-dense Italian dishes were employed to study the effects of chemical and physical characteristics of foods on satiety. The specific satiety was firstly investigated. Then the satiating efficiency was evaluated when each dish was divided into two calorie levels (preloads) before an ad lib meal. Our results suggest that specific satiety differs, depending on the food itself rather than on energy intake. More calories were ingested with the high-energy-dense foods. The Satiating Efficiency Index (SEI) was calculated: fruit salad was the most satiating (SEI = 3.7), followed by mixed boiled vegetables (SEI = 2.4), meat balls (SEI = 1.0), and baked macaroni (SEI = 0.4). Among the variables considered, energy density, volume, protein, and firmness were the most effective in inducing satiety. In conclusion, the consumption of an adequate amount of low-energy-dense foods, high in firmness, as a first course of a meal, can help to decrease short-term intake.

The effects of calories and taste on habituation of the human salivary response

The present study examined the effects of calories on salivary habituation. The rate of habituation to lemon taste was studied over 10 trials in 24 normal weight, nondieting, 18-35-year-old females. Between each of the trials, half the subjects ate low calorie, lemon gelatin, total Kcal = 32, and the others ate high calorie, lemon gelatin, total Kcal = 320. A dishabituating, novel chocolate taste was presented on trial 11 and recovery of salivation was assessed by presenting lemon flavor on trial 12. Subjective ratings were taken before and after salivary habituation for hunger levels and hedonics for lemon taste. Results show that high- and low-calorie groups both habituated to the repeated presentation of lemon taste, but with no significant differences as a function of calories in salivation volume, rate of habituation, hunger level decreases, and hedonic decreases. Subjects in both groups perceived equal caloric intake. These results suggest that salivary habituation may be affected more by the sensory characteristics of the food than by differences in caloric intake. The generalization of these data to the development of satiety are discussed.

Effect of the physical state of a food on subsequent intake in human subjects

The effect of the physical state of food on further intake was studied. Human subjects were served two experimental foods at lunchtime 1 week apart. In a first experiment, the two-food meals had the same caloric content, weight, volume, composition and temperature but differed only in their physical form (solid or liquid). As compared to the solid meal, the 24-h total caloric intake following the liquid food was higher. This difference could be attributed to cognitive cues from the form of food or to the lack of masticatory movements while ingesting the liquid meal. The last hypothesis was tested in a second experiment. "In which the test-meals appeared absolutely identical to the senses and were composed of a liquid and a solid item; however, the major part of calories was either in the liquid or in the solid part. When most of the calories had to be drunk, the total subsequent caloric intake was higher than when the most of the calories had to be eaten. It seems that calories ingested in a liquid form are not well taken in account and could induce a subsequent overconsumption, at least until satiety was conditioned to the fluid.

Acute effects of nicotine on hunger and caloric intake in smokers and nonsmokers

The inverse relationship between smoking and body weight may be due in part to nicotine's effects on reducing hunger and eating. Male smokers and nonsmokers (n = 10 each), abstinent overnight from smoking and food, participated in four sessions, involving consumption of a liquid caloric load or water followed by nicotine (15 micrograms/kg) or placebo via nasal spray every 20 min for 2 h. Hunger and satiety ("fullness") ratings were obtained prior to each dose presentation. At the end of the two sessions involving the caloric load (simulating breakfast), subjects were also presented with typical lunch/snack food items varying in sweet taste and fat content for ad lib consumption. Results indicated that, for both smokers and nonsmokers, the hunger-reducing effects of nicotine occurred only following caloric load consumption, and there was no effect of nicotine on hunger afer water consumption. Smokers unexpectedly reported greater satiation than nonsmokers following the caloric load regardless of nicotine or placebo condition. Nicotine also resulted in less caloric intake during the meal, and the decrease was not specific to consumption of sweet, high-fat foods. These results indicate that nicotine reduces appetite, possibly helping to explain the influence of smoking on body weight.

Hunger ratings are not a valid proxy measure of reported food intake in humans

Hunger ratings have been used as proxy measures of food intake although their validity has not been established. To address this issue, 12 female and 12 male adults of normal weight recorded food intake and hunger ratings every waking hour for 7 consecutive days. Discrepancies were noted in the correlation between hunger ratings and computed energy intake on weekdays vs. weekends, and no significant correlations were observed for individual subjects. Eating often occurred when hunger ratings were low or had not increased, and few individuals displayed a significant correlation between hunger ratings and number of eating occurrences. It was concluded that hunger ratings are not a valid index of energy intake computed from food records or number of eating occurrences.

Effects of aspartame and sucrose on hunger and energy intake in humans

Physiological and behavioral responses to high intensity sweeteners have been poorly characterized, leading to questions regarding their utility in weight management regimens. To address this issue, studies must independently control attributes such as the taste properties, chemical composition and energy contribution of a given sweetener, as well as subject expectations of its effects. In the present study, 24 adults of normal weight consumed breakfasts including unsweetened or sweetened (sucrose or aspartame) cereal for 5 days, during which hunger and energy intake were monitored. The cereals were rated as equally sweet and pleasant and were equicaloric. Half of the subjects were aware of the cereal composition. Neither sweet taste nor aspartame alone significantly affected reported hunger, daily energy intake or subsequent selection of foods with varying taste qualities. Energy intake tended to be more strongly influenced by perceptions of the energy value of the experimental breakfast. Thus, this study failed to find an appetite stimulating effect of either sweetness or sweetener (aspartame or sucrose).

Cognitive restraint and sensitivity to cues for hunger and satiety

The present study provides experimental evidence for the effects of cognitive restraint on sensitivity to internal and external cues of hunger. The design involved four experimental conditions. In each condition the subjects were given either a high calorie or a low calorie early morning drink, and either correctly or incorrectly told its calorie content. The subjects, 10 restrained and 10 nonrestrained normal weight women, then rated their subjective hunger and satiety responses and had a test meal. All subjects reported lower sensations of hunger and higher sensations of fullness after the high calorie drink than the low calorie drink, indicating sensitivity to internal cues. However, the restrained eaters' ratings of hunger were also influenced by the believed content of the drink, indicating sensitivity to external cues. The implications of the results are analysed in terms of current theories of restrained eating and their relevance to further research into pathological eating regulation is discussed.

Hunger and food intake following consumption of low-calorie foods

Although high-intensity sweeteners are widely used to decrease the energy density of foods, little is known about how this affects hunger and food intake. We have studied the effects of consumption of commercially available foods sweetened with either sucrose or aspartame on subjective appetite ratings and food intake. When normal-weight non-dieting males and females were given large portions of either a high- or low-calorie pudding or jello and instructed to eat as much as they liked, they ate similar weights of the different caloric versions of each food. Despite the resulting difference in caloric intake (up to 206 kcal), subjects showed only a non-significant trend towards caloric compensation when presented with a variety of foods 2 h later. Total caloric intake (preload plus test meal) did not differ between conditions. Ratings of hunger, desire to eat, the amount subjects wanted to eat, and the pleasantness of the taste of the eaten food were similarly decreased and fullness similarly increased by consumption of the different caloric versions of the foods. Awareness of the caloric content of the foods did not influence intake or appetite in that both informed and uniformed subjects responded similarly in the tests. Thus reduced calorie foods suppressed ratings of hunger for several hours after consumption, but were not associated with a significant reduction in total energy intake.

Sensory stimulation and energy density in the development of satiety

To determine the contribution of sensory stimulation to the changing hedonic response to foods, the effects of consuming very low-calorie and higher calorie versions of soup and jello on the subjective pleasantness of foods were compared. Subjects were 24 normal weight females with low dietary restraint. Half the subjects were given test meals of low- and high-calorie tomato soup and half were given low- and high-calorie orange jello. They rated the pleasantness of the appearance, smell, texture and taste of nine sample foods as well as hunger and stomach fullness before and 2, 20, 40 and 60 min after consumption of the test meal. After the 60 min rating subjects were offered as much as they wanted to eat of a second course of cheese on crackers. Despite differences in the energy density of the test meals, there were no significant differences in the weights of food eaten in either the first or second course and no significant compensation in the second course for the energy differences of the first course. No differential effects of the caloric manipulation were observed in terms of hunger or fullness or in the development, time course and magnitude of sensory-specific satiety. That very low-calorie foods can produce sensory-specific satiety indicates that the sensory properties of foods are important for the changing hedonic response to foods as they are consumed.