Food for Thought: Reward Mechanisms and Hedonic Overeating in Obesity

PURPOSE OF REVIEW

This review examines the food addiction model and the role of food hedonic pathways in the pathogenesis and treatment of obesity.

RECENT FINDINGS

The hedonic pathway interacts with the obesogenic environment to override homeostatic mechanisms to cause increase in body weight. Weight gain sustained over time leads to "upward setting" of defended level of body-fat mass. There are neurobiological and phenotypic similarities and differences between hedonic pathways triggered by food compared with other addictive substances, and the entity of food addiction remains controversial. Treatment for obesity including pharmacotherapy and bariatric surgery impacts on neural pathways governing appetite and hedonic control of food intake. The food addiction model may also have significant impact on public health policy, regulation of certain foods, and weight stigma and bias. Recent rapid progress in delineation of food hedonic pathways advances our understanding of obesity and facilitates development of effective treatment measures against the disease.

Dietary disinhibition mediates the relationship between poor sleep quality and body weight

BACKGROUND

Inadequate sleep independently influences eating habits and weight status. However, the relationship between these three factors has not been well quantified. The objective of this study was to examine if eating behavior (i.e. dietary restraint, disinhibition and hunger) mediates the relationship between sleep and body mass index (BMI) in a large sample of American adults.

METHOD

Cross-sectional data from the Nathan Kline Institute Rockland sample were assessed (n = 602; 38.9 ± 14.5 years). Self-reported sleep and eating behavior were measured using the Pittsburgh Sleep Quality Index and Three Factor Eating Questionnaire, respectively. Path analysis was used to examine relationships amongst the construct, with mediation tested via bootstrapped confidence intervals.

RESULTS

Poorer sleep quality was associated with both greater hunger (P = 0.03) and higher disinhibited eating (overeating in the presence of palatable foods or other disinhibiting stimuli like emotional stress; P < 0.001) behaviors. Higher disinhibited eating behavior was also associated with higher BMI (P < 0.001). There was a significant indirect relationship between sleep quality and BMI via disinhibition (b [95% CI] = 0.13 [0.06, 0.21], P = 0.001). No significant effects were found when total sleep time or time in bed were replaced as predictors in the mediation model.

CONCLUSION

Disinhibited eating behavior mediated the relationship between sleep quality and weight status in both males and females. This mediation was due to aspects of sleep quality other than duration. These results suggest that improving sleep quality may benefit weight loss by helping to reduce an individuals' susceptibility to overeating.

Mediation and modification of genetic susceptibility to obesity by eating behaviors

Background: Many genetic variants show highly robust associations with body mass index (BMI). However, the mechanisms through which genetic susceptibility to obesity operates are not well understood. Potentially modifiable mechanisms, including eating behaviors, are of particular interest to public health.Objective: Here we explore whether eating behaviors mediate or modify genetic susceptibility to obesity.Design: Genetic risk scores for BMI (BMI-GRSs) were calculated for 3515 and 2154 adults in the Fenland and EDEN (Etude des déterminants pré et postnatals de la santé et du développement de l'enfant) population-based cohort studies, respectively. The eating behaviors-emotional eating, uncontrolled eating, and cognitive restraint-were measured through the use of a validated questionnaire. The mediating effect of each eating behavior on the association between the BMI-GRS and measured BMI was assessed by using the Sobel test. In addition, we tested for interactions between each eating behavior and the BMI-GRS on BMI.Results: The association between the BMI-GRS and BMI was mediated by both emotional eating (EDEN: P-Sobel = 0.01; Fenland: P-Sobel = 0.02) and uncontrolled eating (EDEN: P-Sobel = 0.04; Fenland: P-Sobel = 0.0006) in both sexes combined. Cognitive restraint did not mediate this association (P-Sobel > 0.10), except among EDEN women (P-Sobel = 0.0009). Cognitive restraint modified the relation between the BMI-GRS and BMI among men (EDEN: P-interaction = 0.0001; Fenland: P-interaction = 0.04) and Fenland women (P-interaction = 0.0004). By tertiles of cognitive restraint, the association between the BMI-GRS and BMI was strongest in the lowest tertile of cognitive restraint, and weakest in the highest tertile.Conclusions: Genetic susceptibility to obesity was partially mediated by the "appetitive" eating behavior traits (uncontrolled and emotional eating) and, in 3 of the 4 population groups studied, was modified by cognitive restraint. High levels of cognitive control over eating appear to attenuate the genetic susceptibility to obesity. Future research into interventions designed to support restraint may help to protect genetically susceptible individuals from weight gain.

Appetitive traits associated with higher and lower body mass index: evaluating the validity of the adult eating behaviour questionnaire in an Australian sample

BACKGROUND

The aims of this study were to evaluate the factor structure of the newly developed Adult Eating Behaviour Questionnaire (AEBQ) (Hunot et al., Appetite 105:356-63, 2016) in an Australian sample, and examine associations between the four food approach and four food avoidance appetitive traits with body mass index (BMI).

METHODS

Participants (N = 998) recruited between May and October 2016 via a university research participation scheme and online social network sites completed an online version of the AEBQ and self-reported demographic and anthropometric data. Of the sample, 84.8% were females, 29.6% had completed a university degree and the overall mean age was 24.32 years (SD = 8.32). Confirmatory factor analysis (CFA) was used to test three alternative factor structures (derived from issues raised in the original development study): the original 8 factor model, a 7 factor model with Food Responsiveness and Hunger scales combined, and a 7 factor model with the Hunger scale removed.

RESULTS

The CFA revealed that the original 8 factor model was a better fit to the data than the 7 factor model in which Food Responsiveness and Hunger scales were combined. However, while reliability estimates for 7 of the 8 scales were good (Cronbach's α between 0.70-0.86), the reliability of the Hunger scale was modest (0.67) and dropping this factor resulted in a good fitting model. All food avoidance scales (except Food Fussiness) were negatively associated with body mass index (BMI) whereas Emotional Overeating was the only food approach scale positively associated with BMI.

CONCLUSIONS

The study supports the use of the AEBQ as a reliable and valid measure of food approach and avoidance appetitive traits in adults. Longitudinal studies that examine continuity and stability of appetitive traits across the lifespan will be facilitated by the addition of this measurement tool to the literature.

Food addiction and obesity: unnecessary medicalization of hedonic overeating

The concept of addiction is loaded with connotations and is often used for its political as much as its medical utility. The scientific case for 'food addiction' as a clinical phenotype currently rests on its association with generic diagnostic criteria for substance-related disorders being applied to everyday foods and eating-related problems. This has fused the concept of obesity with addiction regardless of whether it fits the definition. The hedonic, or reward, system can account for the ingestion of foods and drugs, confirming that they share neural substrates that differentiate liking and wanting. These are normal processes that are recruited for natural homeostatic behaviours and can explain the phenomenon of hedonic overeating as a consequence of human motivation pushed to extremes by an obesogenic environment. Food addiction constitutes a medicalization of common eating behaviours, taking on the properties of a disease. The use of this medical language has implications for the way in which society views overeating and obesity.

Television food advertisement exposure and FTO rs9939609 genotype in relation to excess consumption in children

BACKGROUND/OBJECTIVE

Exposure to food advertisements may cue overeating among children, especially among those genetically predisposed to respond to food cues. We aimed to assess how television food advertisements affect eating in the absence of hunger among children in a randomized trial. We hypothesized that the fat mass and obesity-associated gene (FTO) rs9939609 single-nucleotide polymorphism would modify the effect of food advertisements.

SUBJECTS/METHODS

In this randomized experiment, 200 children aged 9-10 years were served a standardized lunch and then shown a 34-min television show embedded with either food or toy advertisements. Children were provided with snack food to consume ad libitum while watching the show and we measured caloric intake. Children were genotyped for rs9939609 and analyses were conducted in the overall sample and stratified by genotype. A formal test for interaction of the food advertisement effect on consumption by rs9939609 was conducted.

RESULTS

About 172 unrelated participants were included in this analysis. Children consumed on average 453 (s.d.=185) kcals during lunch and 482 (s.d.=274) kcals during the experimental exposure. Children who viewed food advertisements consumed an average of 48 kcals (95% confidence interval: 10, 85; P=0.01) more of a recently advertised food than those who viewed toy advertisements. There was a statistically significant interaction between genotype and food advertisement condition (P for interaction=0.02), where the difference in consumption of a recently advertised food related to food advertisement exposure increased linearly with each additional FTO risk allele, even after controlling for body mass index percentile.

CONCLUSIONS

Food advertisement exposure was associated with greater caloric consumption of a recently advertised food, and this effect was modified by an FTO genotype. Future research is needed to understand the neurological mechanism underlying these associations.

Prevalence of 'Food Addiction' as Measured with the Yale Food Addiction Scale 2.0 in a Representative German Sample and Its Association with Sex, Age and Weight Categories

BACKGROUND/AIMS

To assess the prevalence and correlates of addictive-like eating behavior in Germany.

METHODS

The German version of the Yale Food Addiction Scale (YFAS) 2.0 was used to investigate, for the first time, the prevalence of 'food addiction' in a representative sample aged 18-65 years (N = 1,034).

RESULTS

The prevalence of 'food addiction' measured by the YFAS 2.0 was 7.9%. Individuals meeting criteria for 'food addiction' had higher BMI and were younger than individuals not meeting the threshold. Underweight (15.0%) and obese (17.2%) individuals exhibited the highest prevalence rate of 'food addiction'. Addictive-like eating was not associated with sex, education level, or place of residence.

CONCLUSION

YFAS 2.0 'food addiction' was met by nearly 8% of the population. There is a non-linear relationship between addictive-like eating and BMI, with the highest prevalence among underweight and obese persons. These findings suggest that 'food addiction' may be a contributor to overeating but may also reflect a distinct phenotype of problematic eating behavior not synonymous with obesity. Further, the elevated prevalence of YFAS 2.0 'food addiction' among underweight individuals may reflect an overlap with eating disorders and warrants attention in future research.

Overeat today, skip the scale tomorrow: An examination of caloric intake predicting nonadherence to daily self-weighing

OBJECTIVE

Daily self-weighing is an effective weight loss strategy. Little is known about "micro" factors influencing nonadherence to self-weighing (e.g., daily overeating). It was hypothesized that increased caloric intake on a given day would increase odds of not self-weighing the following day.

METHODS

Daily self-reports of weight and caloric intake were collected from 74 adults with overweight and obesity (mean BMI = 31.2 ± 4.5 kg/m² , age = 50.6 ± 10 years, 69% female, 87% Caucasian) throughout a 12-week Internet-based weight management intervention. Multilevel logistic regression investigated odds of nonadherence to self-weighing on a given day based on the previous day's caloric intake.

RESULTS

Self-monitoring adherence was high (weights: 87%; calories: 85%); adherence was associated with greater 12-week weight loss (weighing: r = -0.24, P = 0.04; calories: r = -0.26, P = 0.04). Increased caloric intake on a given day, relative to the individual's average intake, was associated with increased odds of nonadherence to self-weighing the next day (F_(1,5106)  = 12.66, P = 0.0004, β = 0.001). For example, following a day of eating 300 calories more than usual, odds of not self-weighing increased by 1.33.

CONCLUSIONS

Odds of nonadherence to self-weighing increased following a day with higher-than-usual caloric intake. Weight management interventions collecting daily self-monitoring data could provide support to participants who report increased caloric intake to prevent self-weighing nonadherence.

Uninvolved Maternal Feeding Style Moderates the Association of Emotional Overeating to Preschoolers' Body Mass Index z-Scores

OBJECTIVE

To examine the relation between preschoolers' eating behaviors and body mass index (BMI) z-scores (BMIz) and the moderating role of permissive parent feeding styles in these associations.

DESIGN

Cross-sectional study involving mothers' report of food-related parenting styles and child eating behaviors.

SETTING

Small city in southern Mississippi.

PARTICIPANTS

Mother-preschooler dyads (n = 104).

MAIN OUTCOME MEASURE

Child body BMIz.

ANALYSIS

Moderated multiple regression.

RESULTS

An uninvolved feeding style moderated the relationship between emotional eating and BMIz such that children with higher emotional overeating scores had higher a BMIz in the presence of an uninvolved feeding style (B = 2.16; P = .01).

CONCLUSIONS AND IMPLICATIONS

An uninvolved feeding style may be a risk factor for higher BMIz in preschoolers who tend to overeat to cope with negative emotions. For other children in this population, self-regulatory aspects of eating may be more important than mothers' feeding style in the maintenance of healthy weight.

Behavioral consequences of exposure to a high fat diet during the post-weaning period in rats

We explored the impact of exposure to an obesogenic diet (High Fat-High Sucrose; HFS) during the post-weaning period on sweet preference and behaviors linked to reward and anxiety. All rats were fed chow. In addition a HFS-transient group had access to this diet for 10days from post-natal (PN) day 22 and a HFS-continuous group continued access until adult. Behavioral tests were conducted immediately after PN 32 (adolescence) or after PN 60 (adult) and included: the condition place preference (CPP) test for chocolate, sugar and saccharin preference (anhedonia), the elevated plus maze (anxiety-like behavior) and the locomotor response to quinpirole in the open field. Behavior was unaltered in adult rats in the HFS-transient group, suggesting that a short exposure to this obesogenic food does not induce long-term effects in food preferences, reward perception and value of palatable food, anxiety or locomotor activity. Nevertheless, rats that continued to have access to HFS ate less chocolate during CPP training and consumed less saccharin and sucrose when tested in adolescence, effects that were attenuated when these rats became adult. Moreover, behavioral effects linked to transient HFS exposure in adolescence were not sustained if the rats did not remain on that diet until adult. Collectively our data demonstrate that exposure to fat and sucrose in adolescence can induce immediate reward hypofunction after only 10days on the diet. Moreover, this effect is attenuated when the diet is extended until the adult period, and completely reversed when the HFS diet is removed.

Brazilian version of food cravings questionnaires: Psychometric properties and sex differences

The Food Cravings Questionnaires, State (FCQ-State) and Trait (FCQ-Trait), are commonly used to assess food-craving behavior. This study aimed to develop and validate the Brazilian version of these questionnaires, and to explore potential gender differences in the trait version scores. Data were collected from (n = 611) undergraduate students. Confirmatory factor analysis was conducted to examine the questionnaires structure, and construct validity was assessed. The FCQ-State-Br and FCQ-Trait-Br presented good psychometric properties, adequate model fit, and internal consistency, in general and by gender. A conservation of original structure of the Food Cravings Questionnaires was verified in the Brazilian versions. A good performance in the evaluations concerning the discriminant and convergent validity seem to corroborate these structures. Overweight individuals showed an increase in food-craving behavior. In females, this increase occurred in the guilt dimension, whereas in males, the increase was in the lack of control dimension. In addition, female dieters presented higher scores on the guilt dimension compared with female non-dieters. FCQ-State-Br and FCQ-Trait-Br constitute valid instruments for measuring food-craving behavior in the Brazilian population. Moreover, these findings suggest that food cravings may be an important aspect to be considered in clinical management of overweight individuals, and may require a sex-specific approach.

Food addiction associations with psychological distress among people with type 2 diabetes

AIMS

To assess the relationship between a food addiction (FA) model and psychological distress among a type 2 diabetes (t2d) sample.

METHODS

A cross-sectional study of 334 participants with t2d diagnoses were invited to complete a web-based questionnaire. We measured variables of psychological distress implementing the Depression Anxiety and Stress Scale (DASS-21), the Yale Food Addiction Scale (YFAS), and other factors associated with t2d.

RESULTS

In our study a novel finding highlighted people with t2d meeting the FA criterion had significantly higher depression, anxiety, and stress scores as compared to participants who did not meet the FA criterion. Moreover, FA symptomology explained 35% of the unique variance in depression scores, 34% of the unique variance in anxiety scores, and 34% of the unique variance in stress scores, while surprisingly, BMI explained less than 1% of the unique variance in scores.

CONCLUSION

We identified that psychological distress among people with t2d was associated with the FA model, apparently more so than BMI, thereby indicating further research being necessary lending support for future research in this realm. Moreover the FA model may be beneficial when addressing treatment approaches for psychological distress among people with t2d.

Effects of sugar rich diet on brain serotonin, hyperphagia and anxiety in animal model of both genders

Lower levels of 5-hydroxytryptamine (5-HT; serotonin) in the brain elicit sugar craving, while ingestion of sugar rich diet improves mood and alleviates anxiety. Gender differences occur not only in brain serotonin metabolism but also in a serotonin mediated functional responses. The present study was therefore designed to investigate gender related differences on the effects of long term consumption of sugar rich diet on the metabolism of serotonin in the hypothalamus and whole brain which may be relevant with the hyperphagic and anxiety reducing effects of sugar rich diet. Male and female rats were fed freely on a sugar rich diet for five weeks. Hyperphagic effects were monitored by measuring total food intake and body weights changes during the intervention. Anxiolytic effects of sugar rich diet was monitored in light-dark transition test. The results show that ingestion of sugar rich diet decreased serotonin metabolism more in female than male rats. Anxiolytic effects were elicited only in male rats. Hyperphagia was comparable in both male and female rats. Finings would help in understanding the role of sugar rich diet-induced greater decreases of serotonin in sweet craving in women during stress.

Contextual and environmental influences on reported dietary energy intake at evening eating occasions

OBJECTIVE

This study sought to determine the simultaneous effect of immediate eating environment variables; portion size, plate size, proximity to food, variety of food, side serves of salad/vegetables and presence of distraction on dietary energy intake (EI), of a reported evening meal, in the participants' real world setting.

DESIGN

A retrospective computer assisted telephone interview collected data on ten immediate eating environment variables, covariates and a 24-hour dietary recall of EI at an evening meal. Multiple regression analysis was conducted to determine relationships of these variables with EI. Significant (P<0.05) standardised beta coefficients (β) are reported.

SETTING

Australia wide, participants' homes.

SUBJECTS

Australian adult males and females (n 150) aged 18-65years.

RESULTS

Of the immediate eating environment variables, the absence of salads/vegetables (β=0.237), increased food variety (β=0.208), presence of music (β=0.207), and the consumption of pre-plated (as opposed to self-served) meals (β=0.195) had a positive association with EI, explaining 16.3% of the variance. Of the covariates, being male was the strongest predictor of EI (β=0.242); and hunger score also had a positive relationship with EI (β=0.190), explaining 17.5% of the variance.

CONCLUSION

This study provides evidence that some immediate food environment variables at an evening eating occasion are associated with EI. Findings suggest there are several strategies that people could implement to assist in controlling their EI and help address over consumption.

The relationship of alcohol use to weight loss in the context of behavioral weight loss treatment

Despite common wisdom that reducing alcohol intake will facilitate weight loss, little research has examined whether participants in behavioral weight loss treatments actually decrease their alcohol intake, or whether reduced alcohol intake relates to weight loss outcomes in this context. This study examined the relationship of alcohol use to energy intake excluding alcohol and to weight in 283 overweight and obese adults participating in a 26-session behavioral weight loss treatment. The majority of participants consumed low to moderate levels of alcohol at baseline. Participants who consumed alcohol at baseline meaningfully reduced their alcohol intake by end-of-treatment. Alcohol use did not relate to weight at baseline or end-of-treatment when controlling for relevant demographic variables, and change in alcohol use was unrelated to weight change in the overall sample during treatment. However, end-of-treatment alcohol intake did relate to end-of-treatment energy intake excluding alcohol. In addition, behavioral impulsivity and change in alcohol intake interacted to predict weight loss, such that decreases in alcohol intake were associated with greater percent weight loss at end-of-treatment for participants with higher levels of impulsivity. Alcohol consumption may lead to overeating episodes, and highly impulsive individuals may be at risk for increased energy intake during or after episodes of drinking. Therefore, the recommendation to reduce alcohol intake in the context of behavioral weight loss treatment seems warranted, particularly for individuals with high levels of impulsivity.

[Deleterious Results of Safety Seeking Behaviours in Panic Disorder: Polydipsia and Diabetes Mellitus Type 2]

Panic disorder is an anxiety disorder that involves recurrent panic attacks, which emerge when a harmless stimulus is interpreted as "catastrophic". In an attempt to avoid the panic attack or prevent confrontation, the patient exhibits a dysfunctional attitude and behavior, such as evasion and safety-seeking behavior (SSB). Dysfunctional behavior leads to an increase in the recurrence of panic attacks and affects the patient's life in a negative way. According to the cognitive behavioral therapy model, SSB contributes to the continuation of unrealistic beliefs (e.g. physical experiences) regarding and prevents the patient from grasping new information that may potentially contradict the unrealistic cognitions. In this paper, we present a case with a primary diagnosis of panic disorder. Interestingly, this patient developed diabetes mellitus (DM) type 2 and psychogenic polydipsia (PPD) as a consequence of his SSB. PPD is a common occurrence in patients with psychiatric disorders, especially in schizophrenia. Up to now, no case of a panic disorder with either DM or PPD has been reported in the literature. While it is accepted that major depression poses a risk for DM type 2, panic disorder may also increase this risk. Treatment of the panic disorder with cognitive behavioral therapy (CBT) resulted in improvement of PPD and DM type 2. In conclusion, the role of SSB in medical disorders accompanied by psychiatric disorders should be kept in mind when treating these patients.

Inhibitory Control and Hedonic Response towards Food Interactively Predict Success in a Weight Loss Programme for Adults with Obesity

OBJECTIVE

Low inhibitory control and strong hedonic response towards food are considered to contribute to overeating and obesity. Based on previous research, the present study aimed at examining the potentially crucial interplay between these two factors in terms of long-term weight loss in people with obesity.

METHODS

BMI, inhibitory control towards food, and food liking were assessed in obese adults prior to a weight reduction programme (OPTIFAST® 52). After the weight reduction phase (week 13) and the weight loss maintenance phase (week 52), participants' BMI was re-assessed.

RESULTS

Baseline BMI, inhibitory control and food liking alone did not predict weight loss. As hypothesised, however, inhibitory control and food liking interactively predicted weight loss from baseline to week 13 and to week 52 (albeit the latter effect was less robust). Participants with low inhibitory control and marked food liking were less successful in weight reduction.

CONCLUSION

These findings underscore the relevance of the interplay between cognitive control and food reward valuation in the maintenance of obesity.

Roles of "Wanting" and "Liking" in Motivating Behavior: Gambling, Food, and Drug Addictions

The motivation to seek out and consume rewards has evolutionarily been driven by the urge to fulfill physiological needs. However in a modern society dominated more by plenty than scarcity, we tend to think of motivation as fueled by the search for pleasure. Here, we argue that two separate but interconnected subcortical and unconscious processes direct motivation: "wanting" and "liking." These two psychological and neuronal processes and their related brain structures typically work together, but can become dissociated, particularly in cases of addiction. In drug addiction, for example, repeated consumption of addictive drugs sensitizes the mesolimbic dopamine system, the primary component of the "wanting" system, resulting in excessive "wanting" for drugs and their cues. This sensitizing process is long-lasting and occurs independently of the "liking" system, which typically remains unchanged or may develop a blunted pleasure response to the drug. The result is excessive drug-taking despite minimal pleasure and intense cue-triggered craving that may promote relapse long after detoxification. Here, we describe the roles of "liking" and "wanting" in general motivation and review recent evidence for a dissociation of "liking" and "wanting" in drug addiction, known as the incentive sensitization theory (Robinson and Berridge 1993). We also make the case that sensitization of the "wanting" system and the resulting dissociation of "liking" and "wanting" occurs in both gambling disorder and food addiction.

Mothers' feeding behaviors in infancy: Do they predict child weight trajectories?

OBJECTIVE

To determine associations between mothers' feeding behaviors in infancy and children's weight from infancy through to toddlerhood in urban, low-income, minority families and to explore the contribution of concerns about infant eating/weight.

METHODS

One hundred sixty-nine mother-infant dyads (88% African-American) were recruited from an inner city pediatric practice. Questionnaires measuring restrictive feeding, pressuring to eat, and concerns about infant overeating/weight and undereating/weight were administered, and infants weighed and measured, at 6-12 months. Anthropometric data up to 30 months were obtained from multiple (8.9 ± 2.6) well-child visits, with 84% completing 11 visits.

RESULTS

Higher pressuring was associated with lower weight-for-length z-scores (WLZ) over the period from baseline out to 30 months and higher restriction with higher child WLZ over the same period. Pressuring and concern about infant undereating/weight were independently associated with WLZ, but the relationship between restrictive feeding and WLZ was reduced by accounting for concern about infant overeating/weight. Child weight trajectories were not influenced by feeding behavior.

CONCLUSIONS

Mothers restricted heavier infants and pressured leaner infants to eat, and the relationship between restriction and higher infant weight was mediated by concern about infant overeating/weight. Correcting misperceptions and discussing feeding with mothers reporting concern may help prevent excessive early weight gain.

Individuals with Smith-Magenis syndrome display profound neurodevelopmental behavioral deficiencies and exhibit food-related behaviors equivalent to Prader-Willi syndrome

Smith-Magenis syndrome (SMS) is a neurodevelopmental disorder associated with intellectual disability, sleep disturbances, early onset obesity and vast behavioral deficits. We used the Behavior Problems Inventory-01 to categorize the frequency and severity of behavioral abnormalities in a SMS cohort relative to individuals with intellectual disability of heterogeneous etiology. Self-injurious, stereotyped, and aggressive/destructive behavioral scores indicated that both frequency and severity were significantly higher among individuals with SMS relative to those with intellectual disability. Next, we categorized food behaviors in our SMS cohort across age using the Food Related Problems Questionnaire (FRPQ) and found that problems began to occur in SMS children as early as 5-11 years old, but children 12-18 years old and adults manifested the most severe problems. Furthermore, we evaluated the similarities of SMS adult food-related behaviors to those with intellectual disability and found that SMS adults had more severe behavioral problems. Many neurodevelopmental disorders exhibit syndromic obesity including SMS. Prader-Willi syndrome (PWS) is the most frequent neurodevelopmental disorder with syndromic obesity and has a well-established management and treatment plan. Using the FRPQ we found that SMS adults had similar scores relative to PWS adults. Both syndromes manifest weight gain early in development, and the FRPQ scores highlight specific areas in which behavioral similarities exist, including preoccupation with food, impaired satiety, and negative behavioral responses. SMS food-related behavior treatment paradigms are not as refined as PWS, suggesting that current PWS treatments for prevention of obesity may be beneficial for individuals with SMS.

Implications of learning theory for developing programs to decrease overeating

Childhood obesity is associated with medical and psychological comorbidities, and interventions targeting overeating could be pragmatic and have a significant impact on weight. Calorically dense foods are easily available, variable, and tasty which allows for effective opportunities to learn to associate behaviors and cues in the environment with food through fundamental conditioning processes, resulting in measurable psychological and physiological food cue reactivity in vulnerable children. Basic research suggests that initial learning is difficult to erase, and that it is vulnerable to a number of phenomena that will allow the original learning to re-emerge after it is suppressed or replaced. These processes may help explain why it may be difficult to change food cue reactivity and overeating over the long term. Extinction theory may be used to develop effective cue-exposure treatments to decrease food cue reactivity through inhibitory learning, although these processes are complex and require an integral understanding of the theory and individual differences. Additionally, learning theory can be used to develop other interventions that may prove to be useful. Through an integration of learning theory, basic and translational research, it may be possible to develop interventions that can decrease the urges to overeat, and improve the weight status of children.

Weak Satiety Responsiveness Is a Reliable Trait Associated with Hedonic Risk Factors for Overeating among Women

Some individuals exhibit a weak satiety response to food and may be susceptible to overconsumption. The current study identified women showing consistently low or high satiety responses to standardised servings of food across four separate days and compared them on behavioural, psychological and physiological risk factors for overeating and future weight gain. In a crossover design, 30 female participants (age: 28.0 ± 10.6; body mass index (BMI): 23.1 ± 3.0) recorded sensations of hunger in the post-prandial period following four graded energy level breakfasts. Satiety quotients were calculated to compare individuals on satiety responsiveness across conditions. Body composition, resting metabolic rate (RMR), energy intake, food reward and craving, and eating behaviour traits were assessed under controlled laboratory conditions. A distinct low satiety phenotype (LSP) was identified with good consistency across separate study days. These individuals had a higher RMR, greater levels of disinhibition and reported feeling lower control over food cravings. Further, they consumed more energy and exhibited greater wanting for high-fat food. The inverse pattern of characteristics was observed in those exhibiting a consistently high satiety phenotype (HSP). Weak satiety responsiveness is a reliable trait identifiable using the satiety quotient. The LSP was characterised by distinct behavioural and psychological characteristics indicating a risk for overeating, compared to HSP.

The Effects of a Hatha Yoga Intervention on Facets of Distress Tolerance

Individuals with low distress tolerance (DT) experience negative emotion as particularly threatening and are highly motivated to reduce or avoid such affective experiences. Consequently, these individuals have difficulty regulating emotions and tend to engage in maladaptive strategies, such as overeating, as a means to reduce or avoid distress. Hatha yoga encourages one to implement present-centered awareness and non-reaction in the face of physical and psychological discomfort and, thus, emerges as a potential strategy for increasing DT. To test whether a hatha yoga intervention can enhance DT, a transdiagnostic risk and maintenance factor, this study randomly assigned females high in emotional eating in response to stress (N = 52) either to an 8-week, twice-weekly hatha (Bikram) yoga intervention or to a waitlist control condition. Self-reported DT and emotional eating were measured at baseline, weekly during treatment, and 1-week post-treatment. Consistent with prediction, participants in the yoga condition reported greater increases in DT over the course of the intervention relative to waitlist participants (Cohen's d = .82). Also consistent with prediction, the reduction in emotional eating was greater for the yoga condition than the waitlist condition (Cohen's d = .92). Importantly, reductions distress absorption, a specific sub-facet of DT, accounted for 15% of the variance in emotional eating, a hallmark behavior of eating pathology and risk factor for obesity.

Gene × cognition interaction on stress-induced eating: effect of rumination

People often crave for high-caloric sweet foods when facing stress and this 'emotional eating' is a most important cause for weight gain and obesity. Eating under stress contrasts with the normally expected response of a loss of appetite, yet in spite of intensive research from neurobiological and cognitive disciplines we still do not know why stress or negative affect triggers overeating in so many of us. Since the prevalence of overweight and obesity still rises, the discovery of crucial risk factors is a most desirable goal of today's research on sub-optimal eating habits. This paper summarizes the most relevant current knowledge from the (human) literature regarding cognitive and biological vulnerabilities for stress-induced emotional eating. A (non-systematic) review of the most relevant studies reveals that most studies contemplate a rather one-directional way of focusing on either cognitive or biological factors, showing inconsistent results. The current paper elaborates and/or integrates these findings into a biological-cognitive interaction model in which a specific combination of genetic and cognitive vulnerabilities are thought to increase our bio-behavioral response to stress, critically increasing the rewarding value of pleasant foods and, hence, emotional eating.

Behavioral, emotional, and situational context of purging episodes in anorexia nervosa

OBJECTIVE

The current study examined behavioral, emotional, and situational factors involved in purging among women with anorexia nervosa (AN).

METHOD

Women with AN (n=118) completed a two-week ecological momentary assessment protocol involving daily reports of eating disorder behaviors, mood, and stressful events. Generalized estimating equations examined the likelihood and context of purging following eating episodes involving both overeating and loss of control (binge eating; BE); loss of control only (LOC); overeating only (OE); and neither loss of control nor overeating (non-pathological eating; NE).

RESULTS

Relative to NE, purging was more likely to occur following BE, LOC, and OE (Wald chi-square = 18.05; p < .001). BE was more strongly associated with subsequent purging than LOC but not OE; the latter two did not differ from one another. Negative affect predicted purging following NE (Wald chi-square = 7.71; p = .005).

DISCUSSION

Binge eating involving large amounts of food was the strongest predictor of purging in AN, which challenges the notion that loss of control is the most salient aspect of experiencing distress in bulimia nervosa and BE disorder. Parallel to findings from the BE literature, negative affect strongly predicted purging following NE. Further research should clarify the function and triggers of purging in AN.