Effects of manipulated palatability on appetite depend on restraint and disinhibition scores from the Three-Factor Eating Questionnaire

Do eating behavior traits predict energy intake and body mass index? A systematic review and meta-analysis

At present, it is unclear whether eating behavior traits (EBT) predict objectively measured short-term energy intake (EI) and longer-term energy balance as estimated by body mass index (BMI). This systematic review examined the impact of EBT on BMI and laboratory-based measures of EI in adults ( ≥ 18 years) in any BMI category, excluding self-report measures of EI. Articles were searched up until 28th October 2021 using MEDLINE, PsycINFO, EMBASE and Web of Science. Sixteen EBT were identified and the association between 10 EBT, EI and BMI were assessed using a random-effects meta-analysis. Other EBT outcomes were synthesized qualitatively. Risk of bias was assessed with the mixed methods appraisal tool. A total of 83 studies were included (mean BMI = 25.20 kg/m² , mean age = 27 years and mean sample size = 70). Study quality was rated moderately high overall, with some concerns in sampling strategy and statistical analyses. Susceptibility to hunger (n = 6) and binge eating (n = 7) were the strongest predictors of EI. Disinhibition (n = 8) was the strongest predictor of BMI. Overall, EBT may be useful as phenotypic markers of susceptibility to overconsume or develop obesity (PROSPERO: CRD42021288694).

Eating restraint is associated with reduced attentional capture by signals of valuable food reward

Previous paradigms used to examine attentional distraction by task-irrelevant food words and food images were not suited for the investigation of involuntary and automatic attentional capture. In the current experiments we adapted a well-established visual-search paradigm (with eye tracking) to investigate involuntary attentional capture by food and drink rewards. We first used a satiety procedure to manipulate relative preference for different food and drink outcomes (potato chips and water in Experiment 1 and popcorn and chocolate Smarties in Experiment 2). Participants then performed the visual-search task where a coloured distractor signalled on each trial which of the two food and drink rewards was available for successful identification of the target. The signalled reward was cancelled, however, if any eye gaze was registered on the distractor. Participants were therefore motivated to try and control the automatic orienting of attention towards cues signalling valuable outcomes, in order to earn those outcomes. In both experiments we found that attention was more often captured by the distractor signalling the valuable (non-sated) outcome, replicating previous studies using this paradigm with monetary rewards. We also found that those scoring high on eating restraint (as measured with the Dutch Eating Behavior Questionnaire) were better at controlling reflexive orienting of attention to desirable food rewards. This paradigm offers a novel approach for understanding how reflexive attention and control relate to conflicts in everyday life around distracting food cues, and the moderating role of dietary restraint.

The effect of restrained eating on acute stress-induced food intake in people with obesity

Restrained eating, defined as a form of intense dieting or restrictive food intake of specific macronutrients or types of food with sporadic episodes of overeating, results in an increased risk of overweight and obesity. Acute stress situations cause irregular eating patterns and are connected to restrained eating. Therefore, the present study investigates the effect of high/low restrained eating on eating behavior in people with obesity after standardized acute stress induction as well as resting condition. Fifty men and women with obesity (BMI: 33.62 ± 3.93 kg/m²) were categorized into high restrained eaters (HRE) and low restrained eaters (LRE). The total energy intake was measured during a standardized laboratory meal after a resting and stress condition (Trier Social Stress Test) on two separate days. HRE and LRE showed differences in the total energy intake in response to acute stress but not after resting condition (F_{(1, 47)} = 9.188, p = .004, η2 = 0.164). Lower total energy intake after stress compared to resting condition could be observed in HRE (t (23) = -2.617, p = .015). LRE showed higher total energy intake after stress than after resting condition (t (25) = 2.155, p = .041). The present data suggest that restrained eating behavior might be an influencing factor for stress-induced eating in obesity. It is highly necessary to understand the association between restrained eating behavior, acute stress and obesity for the improvement of the behavioral intervention of dietary restriction.

Food Reward and Food Choice. An Inquiry Through The Liking and Wanting Model

What if consumers are getting obese because eating less calories is more difficult for persons that have a higher pleasure and desire towards food (Ikeda et al., 2005) and food companies do not help given only a two extreme option choice to satisfy their needs (i.e., low calories vs. high calories or healthy vs. unhealthy)? Reward systems are being described with a new conceptual approach where liking—the pleasure derived from eating a given food—and wanting—motivational value, desire, or craving—can be seen as the significant forces guiding eating behavior. Our work shows that pleasure (liking), desire (wanting), and the interaction between them influence and are good predictors of food choice and food intake. Reward responses to food are closely linked to food choice, inducing to caloric overconsumption. Based on the responses given to a self-administered questionnaire measuring liking and wanting attitudes, we found three different segments named ‘Reward lovers,’ ‘Half epicurious,’ and ‘Non indulgents’. Their behavior when choosing food is quite different. Results show differential effects on caloric consumption depending on segments. The introduction of more food choices that try to balance their content is a win-win strategy for consumers, companies, and society.

A dual-process psychobiological model of temperament predicts liking and wanting for food and trait disinhibition

A dual-process model of temperament, incorporating the Behavioural Inhibition System (BIS), Behavioural Activation System (BAS) and effortful control (EC), may help to predict hedonic responses to palatable food and trait disinhibition.

PURPOSE

This study aimed to determine if the BIS, BAS and EC predicted liking and wanting for high-fat, sweet foods in adults with overweight and obesity, and if collectively, these variables predicted the eating behaviour trait of Disinhibition.

METHODS

168 adults (104 females, mean BMI = 33.3 kg/m²) completed the Three Factor Eating Questionnaire, the Carver and White BIS/BAS scales, the Adult Temperament Questionnaire-Effortful Control Scale - Short Form and the Leeds Food Preference Questionnaire. The strength of the BIS, BAS and EC in predicting wanting and liking for high-fat sweet foods, and trait Disinhibition was assessed using hierarchical multiple regression.

RESULTS

Both the BIS and EC predicted liking, F (6, 161) = 5.05, p < .001, R² = 0.16, and EC inversely predicted wanting, F (6, 161) = 3.28, p = .005, R² = 0.11. The BIS, EC and liking predicted, F (8, 159) = 11.0, p < .001, R² = 0.36, and explained 36% of Disinhibition. The BAS did not predict wanting, liking or Disinhibition.

CONCLUSIONS

These results demonstrate that a sensitive BIS and a lower level of effortful control predicts food reward and Disinhibition in overweight and obese adults. Consequently, interventions that aim to increase effortful control and reduce BIS reactivity may be beneficial for reducing hedonically motivated, disinhibited eating behaviour.

Validation of a child version of the Three-Factor Eating Questionnaire in a Canadian sample: a psychometric tool for the evaluation of eating behaviour

OBJECTIVE

To examine score validity and reliability of a child version of the twenty-one-item Three-Factor Eating Questionnaire (CTFEQ-R21) in a sample of Canadian children and adolescents and its relationship with BMI Z-score and food/taste preferences.

DESIGN

Cross-sectional study.

SETTING

School-based.

PARTICIPANTS

Children (n 158), sixty-three boys (mean age 11·5 (sd 1·6) years) and ninety-five girls (11·9 (sd 1·9) years).

RESULTS

Exploratory factor analysis revealed that the CTFEQ-R21 was best represented by four factors with item 17 removed (CFFEQ-R20), representing Cognitive Restraint (CR), Cognitive Uncontrolled Eating (UE 1), External Uncontrolled Eating (UE 2) and Emotional Eating (EE), accounting for 41·2 % of the total common variance with good scale reliability. ANOVA revealed that younger children reported higher UE 1 and CR scores than older children, and boys who reported high UE 1 scores had significantly higher BMI Z-scores. Children with high UE 1 scores reported a greater preference for high-protein and -fat foods, and high-fat savoury (HFSA) and high-fat sweet (HFSW) foods. Higher preference for high-protein, -fat and -carbohydrate foods, and HFSA, HFSW and low-fat savoury foods was found in children with high UE 2 scores.

CONCLUSIONS

The study suggests that the CFFEQ-R20 can be used to measure eating behaviour traits and associations with BMI Z-score and food/taste preferences in Canadian children and adolescents. Future research is needed to examine the validity of the questionnaire in larger samples and other geographical locations, as well as the inclusion of extraneous variables such as parental eating or socio-economic status.

Changes in food reward during weight management interventions - a systematic review

BACKGROUND

Does food reward increase or decrease during weight management attempts? Excessive food intake is the main behavioural determinant of obesity; therefore, a better understanding of food reward and its relationship with food intake and weight outcomes could contribute to more effective weight management solutions.

METHODS

This systematic review assessed the role of changes in food reward (directly or indirectly measured) during weight management interventions. Four databases were searched for articles published until April 2018 involving weight management interventions (all types and designs) in healthy adults with overweight or obesity.

RESULTS

Of 239 full-text articles assessed, 17 longitudinal studies were included. Twelve studies reported a significant change in food reward over time. When compared with control interventions, dietary, pharmacological, behavioural and cognitive interventions were effective in decreasing liking and/or wanting for high-energy food using a range of methodologies to assess food reward. Three studies reported that decreased food reward was associated with improved weight management outcomes.

CONCLUSION

Food reward appears to decrease rather than increase during weight management interventions. Future studies specifically targeting the hedonic aspects of food intake (liking/wanting) are needed to gain a better understanding of how to uncouple the obesogenic relationship between food reward and overeating.

Effects of meal palatability on postprandial sensations

BACKGROUND

Food palatability has been shown to influence satiation and meal consumption; our aim was to determine its effects on postprandial satisfaction, ie digestive well-being (primary outcome), and homeostatic sensations (satiety, fullness).

METHODS

Randomized, cross-over trial comparing the postprandial responses to conventional (potato-cheese cream followed by vanilla cream) vs unconventional test meals (mixture of both creams) with identical composition and physical characteristics (color, texture, consistency, temperature) but distinctively different palatability. In 22 non-obese healthy men sensations were measured on 10 cm scales before and during the 60-min postprandial period (-5 to +5 score scales for palatability, satiety, well-being, and mood, and 0-10 score scales for fullness and discomfort). Comparisons between meals were performed with a 2-way repeated measures ANCOVA with premeal data as co-variate.

KEY RESULTS

As compared to the palatable conventional meal, the unconventional meal was rated unpalatable (-1.8 ± 0.4 score vs 2.8 ± 0.1 score potato cream and 2.9 ± 0.2 vanilla cream; P < .001 for both), induced significantly more fullness sensation [meal effect F (1, 19) = 7.389; P = .014] but had less effect on digestive well-being [meal effect F (1, 19) = 47.016; P < .001] and mood [meal-effect F (1, 19) = 6.609; P = .019]. The difference in satiety was not significantly different.

CONCLUSION & INFERENCES

Meal palatability influences the postprandial experience: it bears a direct relation to the hedonic response (well-being/mood) but an inverse relation to homeostatic sensations (fullness). These relations could be applicable to influence eating behavior, because at equal conditions, more palatable meals induce less fullness but more satisfaction, and vice-versa.

Dietary self-control influences top-down guidance of attention to food cues

Motivational objects attract attention due to their rewarding properties, but less is known about the role that top–down cognitive processes play in the attention paid to motivationally relevant objects and how this is affected by relevant behavioral traits. Here we assess how thinking about food affects attentional guidance to food items and how this is modulated by traits relating to dietary self-control. Participants completed two tasks in which they were presented with an initial cue (food or non-food) to either hold in working memory (memory task) or to merely attend to (priming task). Holding food items in working memory strongly affected attention when the memorized cue re-appeared in the search display. Tendency towards disinhibited eating was associated with greater attention to food versus non-food pictures in both the priming and working memory tasks, consistent with greater attention to food cues per se. Successful dieters, defined as those high in dietary restraint and low in tendency to disinhibition, showed reduced attention to food when holding food-related information in working memory. These data suggest a strong top–down effect of thinking about food on attention to food items and indicate that the suppression of food items in working memory could be a marker of dieting success.

Food reinforcement, dietary disinhibition and weight gain in nonobese adults

OBJECTIVE

Food reinforcement is cross-sectionally related to BMI and energy intake in adults, and prospectively predicts weight gain in children, but there has not been any research studying food reinforcement as a predictor of adult weight gain.

DESIGN AND METHODS

This study examined whether the relative reinforcing value of food versus sedentary activities, as measured on a progressive ratio schedule, predicts 12-month weight gain in a sample of 115 nonobese (BMI < 30) adults. Dietary disinhibition and dietary restraint were also examined as potential moderators of this relationship.

RESULTS

In a hierarchical regression controlling for baseline age and weight, dietary hunger, income, sex, and minority status, food reinforcement and predicted weight gain (P = 0.01) significantly increased the variance from 6.3% to 11.7% (P = 0.01). Dietary disinhibition moderated this relationship (P = 0.02) and increased the variance an additional 4.7% (P = 0.02), such that individuals with high food reinforcement had greater weight gain if they were also high in disinhibition.

CONCLUSIONS

These results suggest that food reinforcement is a significant contributor to weight change over time, and food reinforcement may have the biggest effect on those who are most responsive to food cues.

Estimating food portions. Influence of unit number, meal type and energy density

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University staff/students showed poor awareness of appropriate portion sizes.

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Unit number and meal classification affected portion size estimation.

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Portion sizes in sugary drinks, pizza and pasta were underestimated by 30–46%.

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Women were better at estimating food portion sizes than men.

Estimating how much is appropriate to consume can be difficult, especially for foods presented in multiple units, those with ambiguous energy content and for snacks. This study tested the hypothesis that the number of units (single vs. multi-unit), meal type and food energy density disrupts accurate estimates of portion size. Thirty-two healthy weight men and women attended the laboratory on 3 separate occasions to assess the number of portions contained in 33 foods or beverages of varying energy density (1.7–26.8 kJ/g). Items included 12 multi-unit and 21 single unit foods; 13 were labelled “meal”, 4 “drink” and 16 “snack”. Departures in portion estimates from reference amounts were analysed with negative binomial regression. Overall participants tended to underestimate the number of portions displayed. Males showed greater errors in estimation than females (p = 0.01). Single unit foods and those labelled as ‘meal’ or ‘beverage’ were estimated with greater error than multi-unit and ‘snack’ foods (p = 0.02 and p < 0.001 respectively). The number of portions of high energy density foods was overestimated while the number of portions of beverages and medium energy density foods were underestimated by 30–46%. In conclusion, participants tended to underestimate the reference portion size for a range of food and beverages, especially single unit foods and foods of low energy density and, unexpectedly, overestimated the reference portion of high energy density items. There is a need for better consumer education of appropriate portion sizes to aid adherence to a healthy diet.

Verbal descriptors influence hypothalamic response to low-calorie drinks

Messages describing foods constitute a pervasive form of reward cueing. Different descriptions may produce particular appeal depending upon the individual. To examine the extent to which verbal descriptors and individual differences interact to influence food preferences, we used functional magnetic resonance imaging to measure brain responses to the same low-calorie drinks preceded by the spoken verbal descriptor "treat" or "healthy" in 27 subjects varying in BMI, eating style and reward sensitivity. Subjects also sampled a prototypical milkshake treat. Despite the fact that the verbal descriptor had no influence on pleasantness ratings, preferential responses to the low-calorie drinks labeled "treat" vs. "healthy" were observed in the midbrain and hypothalamus. These same regions were also preferentially responsive to the prototypical treat. These results reveal a previously undocumented influence of verbal descriptors on brain circuits regulating energy homeostasis.

Satiety-relevant sensory qualities enhance the satiating effects of mixed carbohydrate-protein preloads

BACKGROUND

Orosensory cues such as food texture and flavor have been shown to play a role in satiation, but their role in satiety remains less clear.

OBJECTIVE

The objective was to determine whether satiety-relevant orosensory cues enhance the satiating effects of energy in the context of beverage preloads.

DESIGN

The effects of 6 drink preloads that combined 2 amounts of energy [high energy (HE): 279 kcal; low energy (LE): 78 kcal] and 3 satiety-relevant sensory contexts [low sensory (LS), medium sensory (MS), and high sensory (HS)] on subsequent appetite and test meal intake were assessed in 36 healthy nonobese volunteers.

RESULTS

The ability of the preloads to modify appetite 30 min after consumption depended on both energy content and sensory context (P-interaction < 0.05), with hunger significantly being lower after consumption of the HE than after the LE preload in the HS context (P < 0.001), tending to be lower in the MS context (P = 0.08), but not different in the LS context. Food intake at lunch was lower after the HE than after the LE preloads (effect of energy P < 0.001), but this effect depended on sensory context (P < 0.005). The degree to which reduced test meal intake compensated for the added energy in the HE preloads was 88% in the HS context, which was significantly greater than in the MS (47%) and LS (18%) contexts.

CONCLUSION

Small changes in the sensory characteristics of drinks altered the degree to which added energy was satiating, which implies that nutrients become more satiating when they are predicted by relevant sensory cues such as thickness and creaminess. This trial was registered at http://www.controlled-trials.com as ISRCTN36258511.

Evaluation of Healthy Choices: A commercial weight loss programme commissioned by the NHS

Aim: The aim of this study is to identify factors that influence successful weight loss in an NHS-funded commercial weight loss programme.

Methods: Baseline height, weight, body mass index (BMI), age, gender, address, date of referral, referrer and 12-week attendance and weight were measured. Participants were classified as having achieved successful weight loss if they had > 5% weight loss and ‘completers’ if they had attended at least 10 of the 12 free sessions. Logistic regression analysis was used to estimate predictors of successful weight loss. Predictors tested in regression analyses were initial weight, number of meetings attended, deprivation, age and gender.

Results: In total, 2,456 (87%) of referred participants were given vouchers to attend a commercial weight loss programme for 12 weeks. The majority of the participants were female and the mean age group was 45–54 years. Almost half (44%) of all patients referred had > 5% weight loss at 12 weeks. A statistically significant difference was found in the mean weight loss between completers (6.1 kg, SD 3.7) and drop outs (2.2 kg, SD 2.5). Participants who had successful weight loss were significantly more likely to be older, male and in obese class I. They were also significantly more likely to have attended more meetings.

Conclusions: Commercial weight loss programmes produce successful weight loss in the short term. There was no difference in successful weight loss between providers and deprivation quintiles. Age, gender, initial BMI and number of meetings attended are all predictors of successful weight loss.

Estimated portion sizes of snacks and beverages differ from reference amounts and are affected by appetite status in non-obese men

Objective

To explore the extent to which appetite status influences portion size estimation in men under laboratory conditions and to quantify how much participants’ portion estimates differed from the recommended portion sizes defined by authoritative bodies (i.e. government and health professionals’ reference amounts).

Design

Repeated, randomized cross-over trial with each participant attending the laboratory on four separate occasions. At each session, participants rated the number of portions of eight foods and beverages displayed in front of them. Participants rated portions twice after consuming breakfast (full conditions) and twice after an overnight fast (hungry conditions). Portion estimates were compared with reference amounts from the British and American Dietetic Associations, from the UK Food Standards Agency and from the US Food and Drug Administration.

Setting

Food skills laboratory, University of Chester, UK.

Subjects

Twenty-seven non-obese men (mean age 24·9 (sd 6·5) years).

Results

Portion size estimates for all items were significantly smaller under hungry than under full conditions (P < 0·01). Relative to reference instruments, estimates were significantly smaller for all foods except banana, irrespective of appetite status (P < 0·001).

Conclusions

In this data set, appetite status altered the perception of food amounts. There were large discrepancies between participants’ perception of a portion and recommendations from health professionals and government standards. Nutritional educational strategies should take into account the role of hunger along with a person's familiarity with existing portion size systems when advising on portion sizes.

Weight outcomes audit for 34,271 adults referred to a primary care/commercial weight management partnership scheme

OBJECTIVE

This project audited rate and extent of weight loss in a primary care/commercial weight management organisation partnership scheme.

METHODS

34,271 patients were referred to Slimming World for 12 weekly sessions. Data were analysed using individual weekly weight records.

RESULTS

Average (SD) BMI change was -1.5 kg/m² (1.3), weight change -4.0 kg (3.7), percent weight change -4.0% (3.6), rate of weight change -0.3 kg/week, and number of sessions attended 8.9 (3.6) of 12. For patients attending at least 10 of 12 sessions (n = 19,907 or 58.1%), average (SD) BMI change was -2.0 kg/m² (1.3), weight change -5.5 kg (3.8), percent weight change -5.5% (3.5), rate of weight change -0.4 kg/week, and average number of sessions attended was 11.5 (0.7) (p < 0.001, compared to all patients). Weight loss was greater in men (n = 3,651) than in women (n = 30,620) (p < 0.001). 35.8% of all patients enrolled and 54.7% in patients attending 10 or more sessions achieved at least 5% weight loss. Weight gain was prevented in 92.1% of all patients referred. Attendance explained 29.6% and percent weight lost in week 1 explained 18.4% of the variance in weight loss.

CONCLUSIONS

Referral to a commercial organisation is a practical option for National Health Service (NHS) weight management strategies, which achieves clinically safe and effective weight loss.

Appetite control: methodological aspects of the evaluation of foods

This report describes a set of scientific procedures used to assess the impact of foods and food ingredients on the expression of appetite (psychological and behavioural). An overarching priority has been to enable potential evaluators of health claims about foods to identify justified claims and to exclude claims that are not supported by scientific evidence for the effect cited. This priority follows precisely from the principles set down in the PASSCLAIM report. The report allows the evaluation of the strength of health claims, about the effects of foods on appetite, which can be sustained on the basis of the commonly used scientific designs and experimental procedures. The report includes different designs for assessing effects on satiation as opposed to satiety, detailed coverage of the extent to which a change in hunger can stand alone as a measure of appetite control and an extensive discussion of the statistical procedures appropriate for handling data in this field of research. Because research in this area is continually evolving, new improved methodologies may emerge over time and will need to be incorporated into the framework. One main objective of the report has been to produce guidance on good practice in carrying out appetite research, and not to set down a series of commandments that must be followed.

Interaction between disinhibition and restraint: Implications for body weight and eating disturbance

An increase in obesity is usually accompanied by an increase in eating disturbances. Susceptibility to these states may arise from different combinations of underlying traits: Three Factor Eating Questionnaire (TFEQ) Restraint and Disinhibition. Two studies were conducted to examine the interaction between these traits; one on-line study (n=351) and one laboratory-based study (n=120). Participants completed a battery of questionnaires and provided self-report measures of body weight and physical activity. A combination of high Disinhibition and high Restraint was associated with a problematic eating behaviour profile (EAT-26), and a higher rate of smoking and alcohol consumption. A combination of high Disinhibition and low Restraint was associated with a higher susceptibility to weight gain and a higher sedentary behaviour. These data show that different combinations of Disinhibition and Restraint are associated with distinct weight and behaviour outcomes.

Disinhibition: its effects on appetite and weight regulation

Over the past 30 years, the understanding of eating behaviour has been dominated by the concept of dietary restraint. However, the development of the Three Factor Eating Questionnaire introduced two other factors, Disinhibition and Hunger, which have not received as much recognition in the literature. The objective of this review was to explore the relationship of the Disinhibition factor with weight regulation, food choice and eating disorders, and to consider its aetiology. The review indicates that Disinhibition is an important eating behaviour trait. It is associated not only with a higher body mass index and obesity, but also with mediating variables, such as less healthful food choices, which contribute to overweight/obesity and poorer health. Disinhibition is also implicated in eating disorders and contributes to eating disorder severity. It has been demonstrated that Disinhibition is predictive of poorer success at weight loss, and of weight regain after weight loss regimes and is associated with lower self-esteem, low physical activity and poor psychological health. Disinhibition therefore emerges as an important and dynamic trait, with influences that go beyond eating behaviour and incorporate other behaviours which contribute to weight regulation and obesity. The characteristics of Disinhibition itself therefore reflect many components representative of a thrifty type of physiology. We propose that the trait of Disinhibition be more appropriately renamed as 'opportunistic eating' or 'thrifty behaviour'.

Leptin-adiposity relationship changes, plus behavioral and parental factors, are involved in the development of body weight in a Dutch children cohort

BACKGROUND

The development of body weight is determined by different factors, namely genetic, behavioral, parental and physiological.

OBJECTIVE

To investigate whether genetic, behavioral, parental and physiological factors are involved and the extent of involvement in the development of body weight at ages 12 and 13 y in a Dutch children cohort.

METHODS

In a Dutch cohort of 94 children at ages 12 and 13 y, we determined anthropometric measurements, body composition, leptin concentrations, TFEQ scores, physical activity, as well as 3 polymorphisms, and in the parents we determined anthropometric measurements and TFEQ scores.

RESULTS

11% of the children in the cohort were classified as overweight. The genotype frequency distributions of the PPARy2, GRL and CNTF genes at ages 12 and 13 y were not significantly different for the overweight children compared to the lean children. Overweight children showed higher dietary restraint and disinhibition scores. Overweight children's parents had a higher BMI, dietary restraint and disinhibition scores, compared to lean children's parents. A peak in leptin concentrations between 7 and 13 y was shown at 12 y. In lean boys, the decrease in leptin concentrations between 12 and 13 y was related to an increase in fat free mass. At the age of 12 y predominantly the physiological factors were predictors for body weight, and at the age of 13 y both the physiological and behavioral factors were predictors for body weight.

CONCLUSION

We conclude from this longitudinal study, that leptin appeared to play an important role in the development of body weight during puberty, in addition to behavioral and parental factors.

Novel calcium-gelled, alginate-pectin beverage reduced energy intake in nondieting overweight and obese women: interactions with dietary restraint status

BACKGROUND

Foods containing strong-gelling fibers may provide a safe and efficacious strategy for reducing food intake by stimulating endogenous satiety signaling.

OBJECTIVE

A novel, 2-part beverage, consisting of alginate-pectin and calcium components, that forms a stable, fibrous gel in the stomach was tested to determine its effects on subjective satiety and food intake in overweight and obese women.

DESIGN

The investigation was a within-subjects, double-blind, placebo-controlled study. Subjects (n = 29) ingested a 2-part beverage twice per day (once before breakfast and once midafternoon) for 7 d. Three alginate-pectin formulations were tested: 1.0 g, 2.8 g, and control (no fiber). Subjective satiety and ad libitum food intake were measured on days 1 and 7 of each 1-wk treatment period with a 1-wk washout between testings.

RESULTS

A significant reduction in food intake was observed at dinner for both formulations compared with the control formulation. The effects of the gel beverage differed as a function of rigid dietary restraint status. Women in the lower 50th percentile of rigid restraint consumed 12% less energy during the day and 22% less for the evening snack in the 2.8-g condition compared with the control condition. No effect was found for women in the upper 50th percentile of rigid restraint.

CONCLUSIONS

Consumption of a postingestion, calcium-gelled fiber beverage twice daily reduced energy intake in overweight and obese women with low rigid restraint scores. Use of foods designed to enhance satiety may be an effective adjunctive therapy for weight loss; however, more research is needed to determine how dietary restraint alters this response.

Hedonic hunger: A new dimension of appetite?

An increasing proportion of human food consumption appears to be driven by pleasure, not just by the need for calories. In addition to its effects on body mass and health, the food environment in affluent societies may be creating an appetitive counterpart to the psychological effects of other hedonically-driven activities such as drug use and compulsive gambling. This phenomenon is referred to here as "hedonic hunger." Animal literature is reviewed indicating that brain-based homeostatic and hedonic eating motives overlap but are nonetheless dissociable. In humans there is evidence that obese individuals prefer and consume high palatability foods more than those of normal weight. Among normal weight individuals it has long been assumed that the appetitive anomalies associated with restrained eating are due to diet-induced challenges to the homeostatic system, but we review evidence suggesting that they more likely stem from hedonic hunger (i.e., eating less than wanted rather than less than needed). Finally, a recently-developed measure (the Power of Food Scale; PFS) of individual differences in appetitive responsiveness to rewarding properties of the food environment is described. Preliminary evidence indicates that the PFS is reliable and valid and is related to clinically-relevant variables such as food cravings and binge eating. This measure, combined with environmental manipulations of food availability and palatability, may constitute a useful approach to studying hedonic hunger.

Liking vs. wanting food: importance for human appetite control and weight regulation

Current train of thought in appetite research is favouring an interest in non-homeostatic or hedonic (reward) mechanisms in relation to overconsumption and energy balance. This tendency is supported by advances in neurobiology that precede the emergence of a new conceptual approach to reward where affect and motivation (liking and wanting) can be seen as the major force in guiding human eating behaviour. In this review, current progress in applying processes of liking and wanting to the study of human appetite are examined by discussing the following issues: How can these concepts be operationalised for use in human research to reflect the neural mechanisms by which they may be influenced? Do liking and wanting operate independently to produce functionally significant changes in behaviour? Can liking and wanting be truly experimentally separated or will an expression of one inevitably contain elements of the other? The review contains a re-examination of selected human appetite research before exploring more recent methodological approaches to the study of liking and wanting in appetite control. In addition, some theoretical developments are described in four diverse models that may enhance current understanding of the role of these processes in guiding ingestive behaviour. Finally, the implications of a dual process modulation of food reward for weight gain and obesity are discussed. The review concludes that processes of liking and wanting are likely to have independent roles in characterising susceptibility to weight gain. Further research into the dissociation of liking and wanting through implicit and explicit levels of processing would help to disclose the relative importance of these components of reward for appetite control and weight regulation.

Determinants of overweight in a cohort of Dutch children

BACKGROUND

To improve the effective prevention and treatment of obesity, it is important to focus on body weight (BW) development and its determinants during childhood.

OBJECTIVE

The aim of the present study was to investigate the effects of early development, parental and genetic variables, and behavioral determinants on overweight at 12 y.

DESIGN

In a Dutch cohort of 105 children, anthropometric measurements were conducted from birth until age 7 y. At age 12 y, anthropometric measurements were obtained again, as were measurements of body composition, leptin concentration, 3 polymorphisms, and physical activity, and the Three-Factor Eating Questionnaire was conducted. In addition, parental body mass indexes (BMIs, in kg/m2) and Three-Factor Eating Questionnaire scores were determined.

RESULTS

The children's mean (+/-SD) BMI at 12 y was 19.0 +/- 2.6, and 15.2% were classified as overweight. From the first year of life, BMI tracked significantly with BMI at age 12 y (r = 0.24, P < 0.05). Linear regression analyses showed that a rapid increase in BW during the first year of life, a high BMI of the father, and a high dietary restraint score of the mother were significantly associated with overweight at age 12 y (P < 0.05). No significant genetic relation was observed. In addition, overweight was positively associated with dietary restraint of the child, and percentage body fat was negatively associated with the child's activity score (P < 0.05).

CONCLUSIONS

In this homogeneous cohort of normal-weight to moderately overweight children, tracking of BMI during childhood took place from the first year of life. Overweight at age 12 y was predicted by an early rapid increase in BW and parental influences. Overweight during childhood may be maintained or even promoted by a high dietary restraint score and low physical activity.

Food intake and reward mechanisms in patients with schizophrenia: implications for metabolic disturbances and treatment with second-generation antipsychotic agents

Obesity is highly prevalent among patients with schizophrenia and is associated with detrimental health consequences. Although excessive consumption of fast food and pharmacotherapy with such second-generation antipsychotic agents (SGAs) as clozapine and olanzapine has been implicated in the schizophrenia/obesity comorbidity, the pathophysiology of this link remains unclear. Here, we propose a mechanism based on brain reward function, a relevant etiologic factor in both schizophrenia and overeating. A comprehensive literature search on neurobiology of schizophrenia and of eating behavior was performed. The collected articles were critically reviewed and relevant data were extracted and summarized within four key areas: (1) energy homeostasis, (2) food reward and hedonics, (3) reward function in schizophrenia, and (4) metabolic effects of the SGAs. A mesolimbic hyperdopaminergic state may render motivational/incentive reward system insensitive to low salience/palatability food. This, together with poor cognitive control from hypofunctional prefrontal cortex and enhanced hedonic impact of food, owing to exaggerated opioidergic drive (clinically manifested as pain insensitivity), may underlie unhealthy eating habits in patients with schizophrenia. Treatment with SGAs purportedly improves dopamine-mediated reward aspects, but at the cost of increased appetite and worsened or at least not improved opiodergic capacity. These effects can further deteriorate eating patterns. Pathophysiological and therapeutic implications of these insights need further validation via prospective clinical trials and neuroimaging studies.

Everyday dietary behaviour and the relationship between attention and meal size

Previously, it has been demonstrated that overeating can occur when an individual engages in a cognitive task during a meal. One possibility, therefore, is that task performance can provide a measure of attention to dietary control. To explore this idea we measured performance on an otherwise irrelevant task during a meal. In two experiments, we compared intake and performance across five groups of females; dieters, and four groups of non-dieters, each with contrasting high and low scores on the restraint scale of the Dutch Eating Behaviour Questionnaire and the disinhibition scale of the Three-Factor Eating Questionnaire. Our analysis suggests that a correspondence can exist between task performance and intake (Experiment 1) and this might be influenced by the extent to which foods are regarded as forbidden (Experiment 2). However, aspects of our data are difficult to reconcile with the idea that task performance reflects a simple measure of attention to dietary control. Instead, one possibility is that individuals differ in the way that they choose to allocate attention during a meal. In relation to this idea, we discuss the possibility that some individuals choose to avoid food-related cognition by engaging strategically with other aspects of their cognitive environment.