A short version of the Food Cravings Questionnaire-Trait: the FCQ-T-reduced

Disentangling inhibition toward food and non-food stimuli across two hunger levels: An fNIRS study

While individuals tend to display poorer inhibitory control toward food-related than neutral stimuli, it is unclear whether this challenge is specific to food or extends to other pleasant stimuli. Uncertainty also remains regarding the general impact of hunger on inhibition. To address these questions, we used a within-subjects design whereby 44 healthy adults completed two go/no-go tasks including no-go images of highly palatable foods and no-go images of animals matched for valence and physical properties. Both tasks were completed one week apart in either a fed or a fasted state. Prefrontal cortex activity was measured using functional near-infrared spectroscopy. Poorer behavioral inhibition was observed when participants needed to withhold their response to images of food compared to animals, regardless of hunger state. In addition, more commission errors were made in the fasted compared to the fed condition, regardless of the type of image to avoid responding to. Responses to go trials were slower when these trials were interspersed with food compared to animal no-go trials. However, hunger did not influence go response time. Greater activation was observed in the dorsolateral prefrontal cortex during blocks of trials with (vs. without) no-go images, but brain activity did not differ according to the type of no-go image. The effect of hunger on prefrontal brain activity was also not significant. Exploratory correlations showed that food-related inhibition deficits were positively related to self-reported impulsivity, but unrelated to body mass index. This study suggests that even among healthy adults, food-related inhibitory control may have a unique behavioral signature beyond general inhibition toward pleasant stimuli. Hunger also exerts an independent influence on general inhibitory capabilities, highlighting the importance of carefully controlling hunger levels in inhibition studies.

The dual-feature approach-avoidance task: validity, training efficacy, and the role of contingency awareness in changing food preference

The approach-avoidance task (AAT) probes tendencies contributing to unwanted behaviours, like excessive snacking, by measuring RT differences between approach and avoidance responses to different stimuli. It retrains such tendencies using repeated avoidance of appetitive stimuli and approach of healthy alternatives. The most common paradigm, the irrelevant-feature AAT, conceals these stimulus-response contingencies by requiring approach or avoidance based on features irrelevant to the tendencies (e.g. frame colour). Unfortunately, it is an unreliable measure and not always successful as a training, likely because the stimuli can be ignored. In the novel dual-feature AAT, the combination of stimulus and irrelevant feature determines responses: participants approach foods and avoid objects surrounded by frame A, and vice versa given frame B. We trained 219 online participants to approach fruit and avoid chocolate using active (7:1 stimulus-to-frame contingency) and sham (1:1 stimulus-to-frame contingency) versions of these two trainings. Compared to sham, active irrelevant-feature training was associated with more selection and desire to eat fruit, and active dual-feature training increased approach bias for fruit. Participants' perceived rate of approaching fruit versus chocolate correlated with many outcome measures, suggesting contingency awareness plays a major role in AAT training effectiveness, challenging implicit accounts. While the dual-feature paradigm shows potential, its high error rates, RTs, and difficulty mandate improvement.

Tackling Cravings in Medical Weight Management: An Update on Pathophysiology and an Integrated Approach to Treatment

Background/Objectives: Food cravings involve a strong drive to consume palatable foods irrespective of nutritional status. Importantly, cravings contribute substantially to the obesity epidemic. Managing hunger alone is insufficient for weight management as this relates only to homeostatic eating and does not address the complex aetiology of hedonic eating and its crucial role in food cravings. Medical weight management clinics and anti-obesity medication trials do not routinely identify and address food cravings. Methods: We conducted a narrative review of the literature consisting of 115 peer-reviewed articles (original articles and reviews). We included articles focused on food craving pathophysiology, assessment, and management strategies providing contrasts against the current medical model of weight management seen in obesity pharmacotherapy trials as well as the current standard of practise. Results: We outline the neurohormonal and psychological drivers of cravings, which lead to a spectrum of eating behaviours, from comfort food eating to binge eating disorders. We provide an overview of ways of identification and measurement options, including their strengths and weaknesses, and an overview of management strategies and their cravings control efficacy, spanning lifestyle modifications like nutrition and sleep, psychological therapies (i.e., cognitive behavioural therapy [CBT], acceptance-based therapies such as mindfulness) and, last but not least, medications that not only are approved for weight reduction but reduce cravings. Finally, based on these findings, we provide a proposed integrated and iterative model that is able to evolve and adapt to the individual over time in tackling cravings for long-term weight loss maintenance. Conclusions: The findings emphasise the importance of cravings management and provide a synthesis on how cravings can be identified in a medical weight management setting, which can be practically implemented in an integrated iterative model spanning anti-obesity medications that have craving control data to evidence-based lifestyle and psychological interventions.

Motor impulsivity and spicy food craving: A mediation analysis of insula-based resting state functional connectivity

In China, the rate of spicy food consumption is rising, and chili pepper is among the most popular spicy foods consumed nationwide. However, little effort has been made to understand the mechanism behind spicy food craving. This exploratory study aimed to investigate differences in insula-based resting state functional connectivity (rsFC) between spicy food cravers and non-cravers, and the association between rsFC, impulsivity and spicy food craving. A group of extreme cravers (n = 49) and a group of age- and sex-matched non-cravers (n = 46) completed a resting-state fMRI scan, during which participants were instructed to keep their eyes closed, to not think of anything in particular, and to remain awake. Participants completed the Spicy Food Craving Questionnaire, Barratt Impulsiveness Scale, Sensation Seeking Scale and Positive and Negative Affect Schedule, and rated the frequency of spicy food intake. Results revealed increased insula-occipital lobe resting-state functional connectivity in individuals with spicy food cravings, and the positive correlations between insula-middle occipital gyrus rsFC, impulsivity and spicy food craving. Specifically, the insula-middle occipital gyrus rsFC strength mediated the relationship between the motor impulsivity and spicy food craving. It is hoped that our exploratory findings may shed new insights into the neural mechanisms of spicy food craving and motivate further exploration of spicy food craving in diverse contexts and cultures.

Efficacy of Dichrostachys Glomerata Supplementation on Overweight and Mildly Obese Adult's Weight, Mood, and Health-Related Quality of Life: A Randomized Double-Blind Placebo-Controlled Trial

Despite their widespread use, research is needed to evaluate the weight loss and related health/wellness outcomes of herbal plants. Preliminary research found that the fruit of Dichrostachys glomerata is safe and has potential weight loss effects. This study aimed to examine the effect of a standardized powder of D. glomerata fruit pods (DYG-400®) on weight, food cravings, mood, and health-related quality of life of overweight and mildly obese adults. In this CONSORT-compliant double-blind placebo-controlled trial, 56 adults (Mean [M] age = 44.50, M [body mass index] BMI = 31.66) were randomized to either the D. glomerata Group (DG; 300 mg/d) or Placebo Group (PG; rice protein, 300 mg/d) for 60 days. Participants weight was assessed along with self-report assessments of the Food Cravings Questionnaire, CDC Health-related Quality of Life, Perceived Stress Scale, Trait Anxiety Inventory, and Profile of Mood States at Baseline, Day 30, and Day 60. The data were collected from March 2023 to June 2023 and stored electronically, and analyzed using general linear models with repeated measures. DG lost more weight at Day 60 compared to PG, p = .05 (4.11 vs. 2.19 lbs). DG had reduced food cravings from Baseline to Day 30 and Day 60 compared to PG, p < .001. Perceived stress, p < .001, and mood, p = .017, improved from Baseline to Day 60 for DG compared to PG. Anxiety decreased from Baseline to Day 60 for DG and from Baseline to Day 30 for PG, p < .001. Health-related Quality of Life improved for DG compared to PG, p < .001. D. glomerata (DYG-400®) may be an effective herbal intervention to promote weight loss and health. Extended clinical trials across diverse populations and settings are needed.

Clinical trial registry number and website: ISRCTN10099861, https://doi.org/10.1186/ISRCTN10099861.

Emotional food craving across the eating disorder spectrum: an ecological momentary assessment study

PURPOSE

Emotional eating during negative emotions might underlie disordered eating behavior (i.e., binge eating and food restriction). Positive emotions, by contrast, seem to promote healthier eating behavior. Naturalistic research on the links between emotions and eating across individuals with binge-eating disorder (BED), bulimia nervosa (BN), binge-purge anorexia nervosa (AN-BP), and restrictive anorexia nervosa (AN-R) is, however, lacking.

METHODS

Individuals without eating disorders (comparison group, CG, n = 85), and patients with BED (n = 41), BN (n = 50), AN-BP (n = 26), and AN-R (n = 29) participated in an ecological momentary assessment study. Six daily notifications over eight days prompted ratings of momentary food craving and emotional states differing in valence and arousal.

RESULTS

Results supported specific emotion-food-craving patterns in each group. Compared to the CG, arousing negative emotions and higher cravings co-occurred in patients with BN. In patients with AN-BP (at trend level also in patients with AN-R) less arousing negative emotions and lower cravings co-occurred. In patients with AN, positive emotions and higher cravings co-occurred whereas in patients with BED less arousing positive emotions and lower cravings co-occurred.

CONCLUSION

The found emotion-craving associations may underlie group-specific (dys-)functional eating behaviors, i.e., binge eating and food restriction during negative emotions in patients with BN and AN, and normalized appetitive responses during positive emotions in patients with BED and AN. Therapeutic efforts could target arousing negative emotions in patients with BN, and less arousing negative emotions in patients with AN. Positive emotions could be used in a salutogenetic approach in patients with BED and AN.

Validity of the Addiction-like Eating Behavior Scale among Patients with Compulsive Eating

Food addiction (FA) and binge eating disorder (BED) co-occur and share compulsive eating symptoms. When using an FA measure, it is important to evaluate its performance in a population presenting compulsive eating. The study aims to validate the Addiction-like Eating Behavior Scale (AEBS) among a clinical sample characterized by compulsive eating and overweight/obesity and to evaluate its incremental validity over the Yale Food Addiction Scale 2.0 (YFAS). Patients seeking help for compulsive eating (n = 220), between January 2020 and July 2023, completed online questionnaires, including FA, compulsive eating, and BMI evaluations. The factor structure, internal consistency, and convergent, divergent, and incremental validity were tested. The sample had a mean age of 44.4 years old (SD = 12.7) and a mean BMI of 38.2 (SD = 8.0). The two-factor structure provided a good fit for the data, with factor loadings from 0.55 to 0.82 (except for item 15) and the internal consistency was high (ω = 0.84-0.89). The AEBS was positively correlated with the YFAS (r = 0.66), binge eating (r = 0.67), grazing (r = 0.47), craving (r = 0.74), and BMI (r = 0.26), and negatively correlated with dietary restraint (r = -0.37), supporting good convergent and divergent validity. For each measure of compulsive eating, linear regression showed that the AEBS "appetite drive" subscale had a unique contribution over the YFAS. This study provided evidence that the AEBS is a valid measure among a clinical sample of patients with compulsive eating and overweight/obesity. However, questions remain as to whether the AEBS is a measure of FA or compulsive eating.

Breadth of substance use is associated with the selection of a larger food portion size via elevated impulsivity

Substance use is associated with altered or elevated food consumption and disordered eating. In the present study we examined whether breadth (variety) of drug use was associated with elevated portion size in a general population sample as it was in persons in recovery from substance use disorder. Furthermore, measures of emotional eating, impulsivity, food misuse, food craving were taken as possible mediators and reward responsiveness was examined as a potential moderator of this association. 444 adults (48.6 % women, mean age of 47.8 years) completed an online study in which they were asked to make judgements of ideal portion size for 6 different foods using a validated online tool that allowed participants to adjust the portion size of images of foods. Ideal portion size has been identified as a strong predictor of actual consumption. Participants were also asked to report the number of substances used in the past and provide anthropometric information. The results confirmed that breadth of drug use was associated with selection of higher portion size. Reward responsiveness was not a moderator of this relationship. Of the tested mediators, only impulsivity mediated the association between breadth of drug use and portion size. The results show that impulsivity may underlie the association between eating and substance use.

Adding thread-embedding acupuncture to auricular acupuncture enhances short-term weight reduction in overweight and obesity: A double-blinded, randomized, sham-controlled trial

Background

Auricular acupuncture (AA) has been widely used in overweight and obesity management due to its safety and effectiveness. The combination of other acupuncture therapies with thread-embedding acupuncture (TEA) has shown enhanced effects. However, there is a lack of evidence regarding AA plus TEA for overweight and obesity. This study was conducted to address this question.

Methods

A randomized placebo-controlled trial was conducted involving 66 overweight or obese participants, divided into two groups: 33 received AA plus TEA, and 33 received AA plus sham TEA over eight weeks. The primary outcome was body weight (BW) reduction. Secondary outcomes included changes in body mass index (BMI) and waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), food cravings questionnaire-trait-reduced (FCQ-Tr) and food craving visual analog scale (VAS) scores. Safety outcomes were adverse events (AEs).

Results

After eight weeks, BW decreased by a mean (SD) of -4.45 (1.29) kg and -2.05 (1.33) kg in the AA plus TEA and AA plus sham TEA groups, respectively (MD [95 % CI]: 2.40 [1.75; 3.05]). BMI, WC, WHR, and food craving VAS score decreased significantly more in the AA plus TEA group than in the AA plus sham TEA group. No significant differences were found in FCQ-Tr and HC between groups. Seven AEs were recorded that were mild and resolved without treatment.

Conclusion

The addition of TEA to AA is a safe and effective management of overweight and obesity. Further studies should incorporate dietary and lifestyle modifications and follow-up after the intervention to assess long-term effectiveness.

Trial registration

The study protocol had been registered on ClinicalTrials.gov (NCT06091761).

Proof-of-concept testing of a mobile application-delivered mindfulness exercise for emotional eaters: RAIN delivered as a step-by-step image sequence

Background

Over fifty percent of individuals with overweight and obesity are emotional eaters. Emotional eating can be theorized as a conditioned response to eat for reasons that are not associated with physiological hunger. We conducted this proof-of-concept study to gather evidence that a mobile app that delivers a common non-meditative mindfulness exercise called RAIN, in a step-by-step image sequence can improve emotional eating and other outcomes over a 3-week period.

Methods

Forty-nine Canadian adults who self reported as emotional eaters (mean age =30.7 years) were recruited through social media and participated in a workshop in which RAIN and its use on the app were introduced. Participants were asked to use the app every time that they experienced a non-homeostatic craving to eat for three weeks. Emotional eating, reactivity to food cravings, perceived loss of control around food, distress tolerance, and eating-specific mindfulness were assessed pre- and post-intervention.

Results

Improvements on all outcomes were found (r-range, -0.58 to -0.28). The feasibility of the mobile application was demonstrated by a low attrition rate (8%), high user satisfaction, and strong app engagement metrics.

Conclusions

The data provide proof-of-concept evidence that a mobile app that delivers a mindfulness exercise in a step-by-step image sequence has potential to be effective and thus identifies a new approach that may reduce emotional eating in an accessible and affordable manner.

Domain-Specific Greed

Greed, the insatiable and excessive desire and striving for more even at the expense of others, may be directed toward various goods. In this article, we propose that greed may be conceptualized as a domain-specific construct. Based on a literature review and an expert survey, we identified 10 domains of greed which we operationalized with the DOmain-SPEcific Greed (DOSPEG) questionnaire. In Study 1 (N = 725), we found support for the proposed structure and convergent validity with related constructs. Bifactor-(S-1) models revealed that generic greed is differentially related to the greed domains, indicating that generic greed primarily captures a striving for money and material things. In the second study (N = 591), we found that greed domains had incremental validity beyond generic greed with regard to corresponding criteria assessed via self- and other-reports. We conclude that greed can be conceptualized as a domain-specific construct and propose an onion model reflecting this structure.

The Effect of Sleep on the Health and Dietary Behaviours of GAA Athletes

Decreased sleep quality and duration is associated with an array of negative health outcomes. Evidence suggests athletes are susceptible to sleep inadequacies that may in turn affect their health and dietary behaviours. This study aimed to explore the sleep profile of both male and female Gaelic games players, at an elite and sub-elite level and compare how poor sleep relates to subjective health complaints and food cravings. One hundred and seventy Gaelic games players completed the Pittsburgh Sleep Quality Index (PSQI), Subjective Health Complaints Inventory (SHC) and Food Cravings Questionnaire-Trait-Reduced (FCQ-T-r). Participants were categorised into two groups: poor sleepers (PSQI ≥ 5) and good sleepers (PSQI < 5). Outcome measures of health and food cravings were analysed across the groups, Mann-Whitney U tests were used to assess differences, and Spearman's rank-order correlations were used to determine relationships between variables. Sixty-seven % of athletes were categorised as poor sleepers. There were no significant differences in PSQI scores across genders (p = 0.088) or playing level (p = 0.072). Poor sleepers experienced significantly increased SHC (p < 0.001) and female athletes had significantly more SHC compared to males (p < 0.001). Female athletes experienced more food cravings than males (p = 0.013). However, there were no significant differences in food cravings between good and poor sleepers (p = 0.104). The findings suggest a high prevalence of poor sleepers amongst GAA athletes. Furthermore, a significant relationship exists between poor sleep and health complaints with females at a higher risk of worsened health complaints and higher food cravings. Sleep screening and education interventions to enhance sleep in GAA athletes are advocated.

A clinical trial protocol of a single-session self-guided acceptance-based online intervention targeting food cravings as predictors of disordered eating in pregnant people

BACKGROUND

Pregnancy is a time of heightened risk for disordered eating behaviors, which are linked to adverse health outcomes in gestation, delivery, and the postpartum. These adverse outcomes may be partially mediated by greater rates of deviation from recommended weight gain trajectories, especially in those who engage in binge and loss of control (LOC) eating. Food cravings are powerful and highly modifiable triggers of binge and LOC eating in non-pregnant populations with preliminary evidence linking cravings to disordered eating behaviors in pregnancy as well. Acceptance-based approaches have been shown to be feasible and effective in reducing the adverse impact of cravings on behavior.

PURPOSE

To test the feasibility, acceptability, and preliminary efficacy of a single-session, self-guided, acceptance-based online workshop targeting food cravings as predictors of binge and LOC eating in pregnancy.

METHODS

We will conduct a pilot randomized controlled trial of a single-session, self-guided online acceptance-based workshop targeting food cravings in pregnancy. Pregnant individuals in the second trimester (n ≥ 74) endorsing current food cravings will be randomly assigned to the intervention or an untreated control group. The intervention group will participate in a one-hour workshop that imparts skills grounded in Acceptance and Commitment Therapy, including acceptance, defusion, and present-moment awareness. Both groups will complete comprehensive self-report assessments of primary outcomes and hypothesized mediators and moderators of intervention efficacy at baseline, one-month follow-up, and at full-term.

CONCLUSION

Results will inform integration of acceptance-based skills targeting food cravings into routine prenatal care to prevent adverse outcomes associated with disordered eating behaviors in pregnancy.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT06129461; registered on November 10, 2023.

Associations between everyday exposure to food marketing and hunger and food craving in adults: An ecological momentary assessment study

Food marketing in television and digital media negatively affects appetitive sensations and eating behaviour in children, but effects are less well understood for outdoor food advertising and adults. This research used Ecological Momentary Assessment (EMA) to explore associations between exposures to food advertising in various contexts (television, digital, outdoors) and adults' hunger and craving for highly advertised food categories. Over one week, participants provided ratings of cravings for types of food (fast food, soft drinks, snacks/confectionery, other) and hunger on a smartphone app up to six times per day when they saw a food advertisement (reactive assessment) and at random intervals (random assessment). Fifty-four participants (70.4 % female; 21.24 ± 3.84 years) provided 1223 assessments (24.7 % reactive, 75.3 % random). Data were analysed in R using multilevel multivariable linear regression models. Participants reported feeling hungrier (X2(1) = 5.85, p = .016, ΔAIC = 3.9) and having stronger cravings (X2(1) = 20.64, p < .001, ΔAIC = 318.6) after seeing food advertisements vs. random assessments. This was driven by greater hunger following television advertising exposure vs. random assessments (β = 1.58, SE = 0.61, p = .010, 95 %CIs 0.38 to 2.78), food advertising via digital devices or outdoors was not associated with hunger. Participants experienced stronger craving after seeing a food advertisement on television (β = 0.52, SE = 0.19, p = .006, 95 %CIs 0.15 to 0.89), outdoors (β = 0.39, SE = 0.12, p < .001, 95 % CIs 0.16 to 0.62) and in digital media (β = 0.36, SE = 0.14, p = .012, 95 % CIs 0.08 to 0.64), vs. random assessments. Cravings were (largely) specific to the advertised food category. EMA can be effective for assessing food marketing associations in adults. The current study provides evidence that food marketing is associated with hunger and craving in adults, which may, with replication, have implications for public health policy.

Brazilian Version of the Yale Food Addiction Scale for Individuals with Severe Obesity

PURPOSE

Adapting and validating the Portuguese version of Br-YFAS 2.0-Obes to allow it to be used by the Brazilian candidates for bariatric surgery.

MATERIALS AND METHODS

This study included 329 individuals with body mass indexes (BMI) ≥ 30 kg/m2, candidates for bariatric surgery at a reference hospital in Brazil. They were given a questionnaire that identified sociodemographic data, and the YFAS 2.0 scale, Portuguese version (BR-YFAS2.0-Obes), was applied to assess their food dependence levels. The Food Craving Questionnaire - Trait: The FCQ-T-reduced was subsequently used for a correlation analysis.

RESULTS

The patients' average BMI was 41.6 ± 8.8 kg/m2. Br-YFAS2.0-Obes presented an average of 4.9 ± 3.1 for the FA diagnostic criteria. The resulting values of the Comparative Fit Index, Tucker Lewis Index, and Standardized Root Mean Square Residual were 0.990, 0.986, and 0.074, respectively. The internal consistency analysis of the 11 domains presented a Kuder-Richardson α of 0.82. The convergent validity, obtained through an analysis of the Pearson correlation coefficient, was r = 0.43 (p < 0.001). It was found that an increase in the number of Br-YFAS 2.0-Obes symptoms is associated with an increase in the FCQ-T-r mean.

CONCLUSION

Much like the YFAS 2.0 in other languages, the BR-YFAS 2.0-Obes presented adequate convergent validity, reliability, and one-factor structure results, which makes it suitable for Brazilian candidates for bariatric surgery or any individual who is within BMI >  = 30 kg/m2.

Imagine chocolate: The craving experience questionnaire in the food domain

Measurement of food craving has gained relevance in the current obesity epidemic. The Craving Experience Questionnaire (CEQ) considers not only craving intensity but also cognitive intrusiveness and imagery vividness as separate craving factors and could thus refine food craving assessment. It is available in two versions with ten items each. The CEQ-F assesses craving frequency across specific time periods and the CEQ-S time-point specific craving strength. Across three independent studies, N = 533 participants completed the German chocolate CEQ-F referenced at the past year to operationalise trait-like craving. Among them, N = 402 also completed the German chocolate CEQ-S referenced at the current moment to operationalise state-like craving. Four-week test-retest reliability was measured. For external validity, we assessed self-reported chocolate consumption, body-mass-index, trait approach motivation, general imagery vividness, and the most widely used food craving questionnaire, namely the Food Cravings Questionnaires in a trait (FCQ-T-r) and state version (FCQ-S), as well as behavioural approach bias (reaction time-based measurement). The three-factor structure was replicated with excellent internal consistency for both CEQ-F and CEQ-S. Test-retest reliability was moderate for both CEQ versions. CEQ-F scores were related to higher levels of chocolate consumption, approach motivation, and FCQ-T-r scores, but not to body-mass-index, imagery vividness, or approach bias. CEQ-S scores were associated with FCQ-S scores and partly with approach bias, but not with approach motivation and imagery vividness. The current results support the factor structure, validity and reliability of the German chocolate CEQ-S and CEQ-F with questions remaining regarding the ability of the CEQ-S to measure state craving. Thus, CEQ-F and CEQ-S usefully contribute to food craving assessment.

Near-infrared spectroscopy and electroencephalography neurofeedback for binge-eating disorder: an exploratory randomized trial

BACKGROUND

Binge-eating disorder (BED) co-occurs with neurobehavioral alterations in the processing of disorder-relevant content such as visual food stimuli. Whether neurofeedback (NF) directly targeting them is suited for treatment remains unclear. This study sought to determine feasibility and estimate effects of individualized, functional near-infrared spectroscopy-based real-time NF (rtfNIRS-NF) and high-beta electroencephalography-based NF (EEG-NF), assuming superiority over waitlist (WL).

METHODS

Single-center, assessor-blinded feasibility study with randomization to rtfNIRS-NF, EEG-NF, or WL and assessments at baseline (t0), postassessment (t1), and 6-month follow-up (t2). NF comprised 12 60-min food-specific rtfNIRS-NF or EEG-NF sessions over 8 weeks. Primary outcome was the binge-eating frequency at t1 assessed interview-based. Secondary outcomes included feasibility, eating disorder symptoms, mental and physical health, weight management-related behavior, executive functions, and brain activity at t1 and t2.

RESULTS

In 72 patients (intent-to-treat), the results showed feasibility of NF regarding recruitment, attrition, adherence, compliance, acceptance, and assessment completion. Binge eating improved at t1 by -8.0 episodes, without superiority of NF v. WL (-0.8 episodes, 95% CI -2.4 to 4.0), but with improved estimates in NF at t2 relative to t1. NF was better than WL for food craving, anxiety symptoms, and body mass index, but overall effects were mostly small. Brain activity changes were near zero.

CONCLUSIONS

The results show feasibility of food-specific rtfNIRS-NF and EEG-NF in BED, and no posttreatment differences v. WL, but possible continued improvement of binge eating. Confirmatory and mechanistic evidence is warranted in a double-blind randomized design with long-term follow-up, considering dose-response relationships and modes of delivery.

Food selection in a buffet scenario by persons in recovery from substance use disorder: Testing a parallel mediation model including impulsivity, food craving, and breadth of drug use

Elevated food cravings and higher food consumption and body weight have been reported in studies of people in recovery from substance use disorder (SUD). In a previous study, SUD recovery status predicted the energy from selected food images in a virtual buffet meal, most strongly in those with high reward responsiveness. The present study was conducted to determine which psychological variables might mediate the relationship between SUD recovery status and food selection and to replicate the finding that reward responsiveness moderated this relationship. In an online study, 216 women and men (109 in recovery from SUD) were asked to choose from among 16 food images in an all-you-can-eat buffet scenario. Food craving, impulsivity, "food addiction", irrational food beliefs, anhedonia, and breadth of drug use were examined as potential mediators while reward responsiveness was examined as a potential moderator. The amount of energy in the selected foods was the outcome variable. Results indicated that breadth of drug use was a mediator; being in SUD recovery predicted higher variety of drug use which predicted higher food selection. However, reward responsiveness did not moderate the relationship between SUD recovery status and energy from the selected foods. Exploratory analysis indicated that lack of premeditation, a measure of impulsivity, with food craving partially mediated the relationship between breadth of drug use and energy from selected foods and that lack of premeditation fully mediated it for sweet foods. The results confirm an association between substance use and food selection and suggest a mechanism via impulsivity.

Goal pursuit increases more after dietary success than after dietary failure: examining conflicting theories of self-regulation using ecological momentary assessment

BACKGROUND

Maintaining a healthy body weight and reaching long-term dietary goals requires ongoing self-monitoring and behavioral adjustments. How individuals respond to successes and failures is described in models of self-regulation: while cybernetic models propose that failures lead to increased self-regulatory efforts and successes permit a reduction of such efforts, motivational models (e.g., social-cognitive theory) make opposite predictions. Here, we tested these conflicting models in an ecological momentary assessment (EMA) context and explored whether effort adjustments are related to inter-individual differences in perceived self-regulatory success in dieting (i.e., weight management).

METHODS

Using linear mixed effects models, we tested in 174 diet-interested individuals whether current day dietary success or failure (e.g., on Monday) was followed by self-regulatory effort adjustment for the next day (e.g., on Tuesday) across 14 days. Success vs. failure was operationalized with two EMA items: first, whether food intake was higher vs. lower than usual and second, whether food intake was perceived as more vs. less goal-congruent than usual. Trait-level perceived self-regulatory success in dieting was measured on a questionnaire.

RESULTS

Intended self-regulatory effort increased more strongly after days with dietary success (i.e., eating less than usual / rating intake as goal-congruent) than after days with dietary failure (i.e., eating more than usual / rating intake as goal-incongruent), especially in those individuals with lower scores on perceived self-regulatory success in dieting.

CONCLUSIONS

Findings support mechanisms proposed by social-cognitive theory, especially in unsuccessful dieters. Thus, future dietary interventions could focus on preventing the decrease in self-regulatory effort after instances of dietary failures and thereby mitigate the potential risk that a single dietary failure initiates a downward spiral into unhealthy eating.

Psychometric validation of four-item exercise identity and healthy-eater identity scales and applications in weight loss maintenance

BACKGROUND

Identifying as someone who engages in health promoting behaviors like healthy eating and exercising may be associated with sustained engagement in those behaviors, but reliable and valid instruments are needed to improve the rigor of this research. Two studies were conducted to (1) examine the psychometric properties of a four-item exerciser identity measure (4-EI) and an adapted healthy-eater identity measure (4-HEI) and (2) examine differences in identity strengths across categories of weight loss success.

METHODS

Data from 1,709 community dwelling adults in the International Weight Control Registry (IWCR) were used. A random half of the sample was used to assess the proposed unidimensional factor structure of the 4-EI and 4-HEI and examine convergent and discriminant validity using Spearman rank-order correlations. One-way ANOVA was used in the other random half of the sample to compare 4-EI and 4-HEI scores (-3 to + 3) across three self-defined weight loss categories ('Successful', 'Regain', and 'Unsuccessful') and those maintaining ≥ 5% weight loss for > 1 year vs. not.

RESULTS

Results support the unidimensional factor structure with all four items (eigenvalue scores > 2.89) as well as convergent and discriminant validity for both measures. Exercise identity was strongly correlated with self-reported physical activity (r (735) = 0.52, p <.001) and measures of autonomous motivation. Healthy eating identity was moderately correlated with cognitive restraint in eating (r (744) = 0.42, p <.001) and other measures predictive of eating behavior. 4-EI and 4-HEI are stronger in Successful (4-EI: M = 0.90, SD = 1.77; 4-HEI: M = 1.56 SD = 1.37) vs. Regain (4-EI: M=-0.18, SD = 1.68; 4-HEI: M =.57, SD = 1.48) and Unsuccessful (4-EI:M=-0.28, SD = 1.62; 4-HEI: M = 0.51, SD = 1.33) and those maintaining ≥ 5% weight loss (4-EI:M = 0.47, SD = 1.78; 4-HEI: M = 1.13, SD = 1.49) vs. not (4-EI:M=-0.27, SD = 1.66; 4-HEI: M = 0.53, SD = 1.47), p's < 0.001.

CONCLUSIONS

The 4-EI and 4-HEI have acceptable psychometric properties and can advance understanding of the role of identity in exercise and dietary behaviors and weight loss maintenance.

TRIAL REGISTRATION

The parent observational study, International Weight Control Registry (IWCR), for these sub-studies is registered in ClinicalTrials.gov (NCT04907396).

Noradrenergic control of neurobehavior in human binge-eating disorder and obesity (NOBEAD): A smartphone-supported behavioral emotion regulation intervention study protocol integrating molecular brain imaging

OBJECTIVE

The neurobehavioral underpinnings of binge-eating disorder (BED), co-occurring with obesity (OB), are largely unknown. This research project conceptualizes BED as a disorder with dysfunctional emotion regulation (ER) linked with changes in central noradrenaline (NA) transmission and NA-modulated neuronal networks.

METHODS

We expect abnormalities in NA activity in both BED and OB, but most pronounced in BED. We expect these abnormalities to be modifiable through state-of-the-art ER intervention, specifically in BED. To assess the role of NA transmission, we will quantify changes in NA transporter (NAT) availability using the highly NAT-specific [11 C]methylreboxetin (MRB) and positron emission tomography-magnetic resonance imaging (PET-MRI) that allows measuring molecular and neuronal changes before and after an ER intervention. Individual 12-session smartphone-supported acceptance-based behavioral therapy will be conducted to improve ER. Thirty individuals with OB and BED (OB + BED), 30 individuals with OB without BED (OB - BED), and 20 individuals with normal weight will undergo assessments of NAT availability and neuronal network activity under rest and stimulated conditions, clinical interviews, self-report questionnaires on eating behavior, ER, mental and physical health, and quality of life, and neuropsychological tests on executive function. Afterwards, in an experimental randomized-controlled design, individuals with OB + BED and OB - BED will be allocated to smartphone-supported ER intervention versus a waitlist and re-assessed after 10 weeks.

DISCUSSION

By obtaining biological and behavioral markers, the proposed study will disentangle the involvement of NAT and the central NA system in the modulation of emotion-supporting neuronal networks that influence eating behavior. Neurobehavioral mechanisms of change during an ER intervention will be determined.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS): DRKS00029367.

PUBLIC SIGNIFICANCE

This study investigates the central noradrenaline system by using hybrid brain imaging in conjunction with emotion regulation as a putative core biological mechanism in individuals with obesity with or without binge-eating disorder that is targeted by emotion regulation intervention. The results will provide a molecular signature beyond functional imaging biomarkers as a predictive biomarker toward precision medicine for tailoring treatments for individuals with binge-eating disorders and obesity.

The New Zealand eating behavior questionnaire - Validation study for a novel assessment tool to describe actionable eating behavior traits

Individualised management of obesity remains challenging and, to date, most treatment is based on clinical judgement. This study aimed to develop and validate a novel questionnaire-based tool to identify three pre-defined eating behavior (EB) traits, emotional eating, reduced satiety (constant hunger) and reduced satiation (feasters) that may predict selective medication response given their targeted actions. We recruited 977 individuals from a tertiary academic diabetes clinic to participate in this two-phase validation study. Participants self-reported weight management activities and were asked to self-assess their EB characteristics. The initial questionnaire included 42 visual analogue scale questions. In Phase I, 729 participants completed the questionnaire, including Māori (11.8%) and Pacific peoples (19.3%). After random division of the study sample, Exploratory Factor Analysis (EFA) confirmed a three-factor model as the best fit. Stepwise removal of items with inadequate factor loading retained 27 of 42 items, which accounted for 96% of the variance. Confirmatory Factor Analysis (CFA), performed on the second half of the sample, demonstrated good model fit with the final 27-item questionnaire. Internal consistency was high for factor (α = 0.82-0.95) and demographic subgroups, and similar to those obtained in the EFA. Test-retest reliability in a subset of 399 participants who repeated the questionnaire after a four-week interval (Phase II) showed moderate to good reliability. Participants classified into one of three EB types based on the highest median score among the factors. Test-retest reliability was robust for emotional eaters (71.25%) and constant hunger (68.9%). The correlation between aggregate EB score (sum of three EB scores) and BMI was significant (Spearman rho = 0.314, P = .0005). The questionnaire reliably identified three distinct EB traits, which may be informative for precision medicine applications for obesity management.

Predictors of neurofeedback treatment outcome in binge-eating disorder: An exploratory study

OBJECTIVE

Knowledge on predictors for treatment response to psychotherapy in binge-eating disorder (BED) is mixed and not yet available for increasingly popular neurofeedback (NF) treatment targeting self-regulation of aberrant brain activity. This study examined eating disorder- and psychopathology-related predictors for NF treatment success in BED.

METHOD

Patients with BED (N = 78) were randomized to 12 sessions of real-time functional near-infrared spectroscopy (rtfNIRS)-NF, targeting individual prefrontal cortex signal up-regulation, electroencephalography (EEG)-NF, targeting down-regulation of fronto-central beta activity, or waitlist (WL). The few studies assessing predictors for clinical outcomes after NF and evidenced predictors for psychotherapy guided the selection of baseline eating disorder-related predictors, including objective binge-eating (OBE) frequency, eating disorder psychopathology (EDP), food cravings, and body mass index (BMI), and general psychopathology-related predictors, including depressive and anxiety symptoms, impulsivity, emotion dysregulation, and self-efficacy. These questionnaire-based or objectively assessed (BMI) predictors were regressed on outcomes OBE frequency and EDP as key features of BED at post-treatment (t1) and 6-month follow-up (t2) in preregistered generalized mixed models (https://osf.io/4aktp).

RESULTS

Higher EDP, food cravings, and BMI predicted worse outcomes across all groups at t1 and t2. General psychopathology-related predictors did not predict outcomes at t1 and t2. Explorative analyses indicated that lower OBE frequency and higher self-efficacy predicted lower OBE frequency, and lower EDP predicted lower EDP after the waiting period in WL.

DISCUSSION

Consistent with findings for psychotherapy, higher eating disorder-related predictors were associated with higher EDP and OBE frequency. The specificity of psychopathological predictors for NF treatment success warrants further examination.

PUBLIC SIGNIFICANCE

This exploratory study firstly assessed eating disorder- and psychopathology-related predictors for neurofeedback treatment outcome in binge-eating disorder and overweight. Findings showed an association between higher eating disorder symptoms and worse neurofeedback outcomes, indicating special needs to be considered in neurofeedback treatment for patients with a higher binge-eating disorder symptom burden. In general, outcomes and assignment to neurofeedback treatment may be improved upon consideration of baseline psychological variables.

Temporal dynamics of mental imagery, craving and consumption of craved foods: an experience sampling study

Objective: According to the elaborated intrusion theory of desire, an initial thought about a wanted substance is elaborated with mental imagery, which increases craving and the probability of consuming the substance. We used an app-assisted experience sampling approach to test this theory in the context of food craving and eating.Design: Overall, 221 females (mean age = 21 years; mean body mass index = 22) reported craving, mental imagery, and food consumption six times per day (2 h intervals) for seven consecutive days. Additionally, two traits (general food craving and imagery ability) were assessed.Main outcome measures: craving intensity, food consumption.Results: The probability of eating a craved food increased if the vividness of the mental food image and craving intensity increased two hours before - independent of trait food craving and trait imagery ability. We also found evidence of controlled eating behavior, with participants consuming the food they craved in only 38% of the cases.Conclusion: Mental imagery vividness and craving intensity predict consumption of craved food. The association between craving and eating might be stronger in individuals who struggle with controlling their eating behavior. Therefore, future studies should examine these relationships in overweight/obese samples or patients with eating disorders.

The effects of intermittent fasting diet alone or in combination with probiotic supplementation in comparison with calorie-restricted diet on metabolic and hormonal profile in patients with polycystic ovary syndrome: study protocol for a randomized clinical trial

INTRODUCTION

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in females characterized by ovulatory dysfunction, hyperandrogenism, and other metabolic disorders. Both intermittent fasting and specific probiotics have been suggested to help improve patients with PCOS through changes in gut microbial composition, circadian clock, and metabolic regulation. Therefore, the present study aims to investigate the effects of intermittent fasting alone or in combination with probiotic supplementation compared to the calorie-restricted (CR) diet on anthropometric measures, metabolic status, inflammation, and oxidative stress in women with PCOS.

METHODS

We will carry out a randomized clinical trial for 8 weeks. Participants will be randomly assigned (1:1:1) to one of the three groups: (1) a 14:10 early time-restricted feeding (TRF) diet with probiotic supplementation (n = 30); (2) a 14:10 early TRF diet with placebo supplementation (n = 30); (3) a CR diet (energy-restricted 25% of required calories) with placebo supplementation as a control group (n = 30). The primary outcomes will be changes in body weight and insulin resistance. However, glycemic control, lipid profile, metabolic parameters, sex hormone-binding globulin, dehydroepiandrosterone, anti-Mullerian hormone, free androgen index, hirsutism, acne, antioxidant and oxidant status, inflammation, anthropometric measures, mental health, sleep quality, appetite, eating behavior, food craving, and blood pressure are secondary outcomes. All outcomes of this study will be evaluated in pre- and post-intervention.

DISCUSSION

We hypothesized that 10-h TRE administered alone or in combination with probiotic supplementation to overweight and obese PCOS subjects would lead to weight loss and improved metabolic, hormonal, inflammatory, and antioxidant markers compared to control subjects following a standard 3-meal-per-day CR diet.

ETHICAL ASPECTS

The current trial received approval from the Medical Ethics Committee of Tehran University of Medical Sciences, Tehran, Iran (IR.TUMS.MEDICNE.REC.1401.425).

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20121110011421N5. Registered on 3 October 2022.

Obesity and hyperandrogenism are implicated with anxiety, depression and food cravings in women with polycystic ovary syndrome

INTRODUCTION

PCOS is associated with mood/eating disorders. Negative body image due to obesity, acne, hirsutism seems to play significant role, but hormonal derangements are probably implicated.

AIM

To investigate the relation between insulin resistance (IR), obesity and hyperandrogenism with mood and eating disorders in women with PCOS.

METHODS

Forty-nine (60.5%) PCOS women and 32(39.5%) age- and BMI-matched healthy controls were enrolled. Emotional/food disorders were evaluated by using self-administered questionnaires: Eating Attitudes Test (EAT)-26, Beck Depression Inventory-II (BDI-II), Hamilton anxiety scale (HAS) and Food Craving Questionnaire-Trait (FCQ-T).

RESULTS

The two groups had no significant differences regarding age, BMI and HOMA2-IR. PCOS women had significantly higher DHEA-S (p < 0.0001), Δ4Α (p < 0.0001) and Testosterone (p < 0.0001). When the two groups were subclassified according to the BMI, in lean (BMI < 25 kg/m2) or overweight (BMI ≥ 25 kg/m2), no significant differences were found with respect to EAT-26 and HAS. BDI-II was associated with obesity (overweight vs lean PCOS: 20.5 ± 6.4 vs 9.8 ± 3.9; p = 0.037) and hyperandrogenism (overweight PCOS vs overweight controls: 20.5 ± 6.4 vs 14.8 ± 8.1; p < 0.0001; lean PCOS vs overweight controls: 16.7 ± 4.7 vs 14.8 ± 8.1; p = 0.01). Additionally, a significant correlation between BDI-II and DHEA-S (rho = 0.305; p = 0.006), Δ4Α (rho = 0.259; p = 0.02) and Testosterone (rho = 0.328; p = 0.003) was reported. FCQ-T was associated with obesity (overweight PCOS vs lean PCOS: 47.6 ± 9.9 vs 29.3 ± 8.9; p < 0.0001; overweight controls vs lean PCOS: 45.5 ± 15.7 vs 29.3 ± 8.9; p < 0.0001), whereas a correlation between FCQ-T and BMI (rho = 0.593; p = 0.0001), waist circumference (rho = 0.554; p = 0.0001) and HOMA2-IR (rho = 0.328; p = 0.003) was documented.

CONCLUSIONS

Obesity and hyperandrogenism increase the risk of depression and food cravings in women with PCOS, leading to a vicious circle of further aggravation of obesity and metabolic syndrome.

No effect of prefrontal transcranial direct current stimulation (tDCS) on food craving, food reward and subjective appetite in females displaying mild-to-moderate binge-type behaviour

Previous work suggests there may be an effect of transcranial direct current stimulation (tDCS) on appetite control in people at risk of overconsumption, however findings are inconsistent. This study aimed to further understand the potential eating behaviour trait-dependent effect of tDCS, specifically in those with binge-type behaviour. Seventeen females (23 ± 7 years, 25.4 ± 3.8 kg m-2) with mild-to-moderate binge eating behaviour completed two sessions of double-blind, randomised and counterbalanced anodal and sham tDCS applied over the right dorsolateral prefrontal cortex at 2.0 mA for 20 min. Subjective appetite visual analogue scales (VAS), the Food Craving Questionnaire-State (FCQ-S), and Leeds Food Preference Questionnaire (LFPQ) were completed pre- and post-tDCS. Participants then consumed a fixed-energy meal, followed by the VAS, FCQ-S and LFPQ. No difference between pre- and post-tDCS scores were found across fullness (p = 0.275, BF10 = 0.040), prospective consumption (p = 0.127, BF10 = 0.063), desire to eat (p = 0.247, BF10 = 0.054) or FCQ-S measures (p = 0.918, BF10 = 0.040) when comparing active and sham protocols. Only explicit liking and wanting for high-fat sweet foods were significantly different between conditions, with increased scores following active tDCS. When controlling for baseline hunger, the significant differences were removed (p = 0.138 to 0.161, BF10 = 0.810 to 1.074). The present data does not support the eating behaviour trait dependency of tDCS in a specific cohort of female participants with mild-to-moderate binge eating scores, and results align with those from individuals with healthy trait scores. This suggests participants with sub-clinical binge eating behaviour do not respond to tDCS. Future work should further explore effects in clinical and sub-clinical populations displaying susceptibility to overconsumption and weight gain.

Genetic Correlates as a Predictor of Bariatric Surgery Outcomes after 1 Year

This study analyzed genetic risk assessments in patients undergoing bariatric surgery to serve as a predictive factor for weight loss parameters 1 year after the operation. Thirty (30) patients were assessed for Genetic Addiction Risk Severity (GARS), which analyzes neurogenetic polymorphisms involved in addiction and reward deficiency. Genetic and psychosocial data collected before the operation were correlated with weight loss data, including changes in weight, body mass index (BMI), and percent of expected weight loss (%EWL). Results examined correlations between individual gene risk alleles, 1-year body weight data, and psychosocial trait scores. Spearman's correlations revealed that the OPRM1 (rs1799971) gene polymorphism had significant negative correlation with 1-year weight (rs = -0.4477, p < 0.01) and BMI (rs = -0.4477, p < 0.05). In addition, the DRD2 risk allele (rs1800497) was correlated negatively with BMI at 1 year (rs = -0.4927, p < 0.05), indicating that one risk allele copy was associated with lower BMI. However, this allele was positively correlated with both ∆Weight (rs = 0.4077, p < 0.05) and %EWL (rs = 0.5521, p < 0.05) at 1 year post-surgery. Moreover, the overall GARS score was correlated with %EWL (rs = 0.4236, p < 0.05), ∆Weight (rs = 0.3971, p < 0.05) and ∆BMI (rs = 0.3778, p < 0.05). Lastly, Food Cravings Questionnaire (FCQ) scores were negatively correlated with %EWL (rs = -0.4320, p < 0.05) and ∆Weight at 1 year post-surgery (rs = -0.4294, p < 0.05). This suggests that individuals with a higher genetic addiction risk are more responsive to weight loss treatment, especially in the case of the DRD2 polymorphism. These results should translate clinically to improve positivity and attitude related to weight management by those individuals born with the risk alleles (rs1800497; rs1799971).

Mindfulness-Based Mobile Health to Address Unhealthy Eating Among Middle-Aged Sexual Minority Women With Early Life Adversity: Mixed Methods Feasibility Trial

BACKGROUND

Sexual minority women (lesbian, gay, bisexual, pansexual, queer, and other nonheterosexual women) remain considerably underrepresented in health research despite being at a higher risk for diabetes and obesity as well as stigma and psychological distress than their heterosexual peers. In addition, early life adversity (ELA) is prevalent among sexual minority women, which further increases risks for obesity, psychological distress, and poor cardiovascular health. App-based mindfulness interventions are potentially promising for this group in mitigating the adverse health effects of ELA, reducing food craving and unhealthy eating, addressing the risks associated with obesity.

OBJECTIVE

This mixed methods feasibility trial aimed to test a mindfulness-based mobile health approach for middle-aged sexual minority women (aged 30-55 years) with ELA and overweight or obesity (BMI ≥25 kg/m2) to improve health outcomes.

METHODS

The single-arm trial was advertised on social media and various lesbian, gay, bisexual, transgender, and queer web-based groups. At baseline, after the intervention (2 months), and at the 4-month follow-up, participants completed assessments of primary outcomes (food craving, emotional eating, and weight via a mailed scale) and secondary outcomes (depression, anxiety, mindfulness, and emotion dysregulation). A standardized weight measure was mailed to participants for weight reporting. Feasibility and acceptability were assessed after the intervention via surveys and semistructured exit interviews.

RESULTS

We screened 442 individuals, among which 30 eligible sexual minority women (mean age 40.20, SD 7.15 years) from various US regions were enrolled in the study. At baseline, 86% (26/30) and 80% (24/30) of participants had elevated depressive and anxiety symptoms, respectively. Among the 30 enrolled participants, 20 (66%) completed all intervention modules, 25 (83%) were retained at the 2-month follow-up, and 20 (66%) were retained at the 4-month follow-up. None reported adverse effects. From baseline to the 4-month follow-up, large effects were found in food craving (Cohen d=1.64) and reward-based eating (Cohen d=1.56), whereas small effects were found with weight (Cohen d=0.20; 4.21 kg on average). Significant improvements were also found in the secondary outcomes (depression, Cohen d=0.98; anxiety, Cohen d=0.50; mindfulness, Cohen d=0.49; and emotion dysregulation, Cohen d=0.44; all P<.05). Participants with higher levels of parental verbal and emotional abuse were particularly responsive to the intervention. Participants reported that the program aligned with their goals and expectations, was easy to use, and facilitated changes in eating behavior and mental health. Barriers to engagement included the need for diverse teachers, individualized support, and body positive language.

CONCLUSIONS

This early phase feasibility trial provides proof-of-concept support for a mindfulness mobile health approach to improve obesity-related outcomes among sexual minority women and warrants a larger randomized controlled trial in the future. The findings also suggest the need to address trauma and psychological health when addressing weight-related outcomes among sexual minority women.

The First Exploratory Personalized Medicine Approach to Improve Bariatric Surgery Outcomes Utilizing Psychosocial and Genetic Risk Assessments: Encouraging Clinical Research

It is predicted that by 2030, globally, an estimated 2.16 billion adults will be overweight, and 1.12 billion will be obese. This study examined genetic data regarding Reward Deficiency Syndrome (RDS) to evaluate their usefulness in counselling patients undergoing bariatric surgery and gathered preliminary data on the potential use in predicting short term (6-month) weight loss outcomes. Methods: Patients undergoing bariatric surgery (n = 34) were examined for Genetic Addiction Risk Severity (GARS) [measures the presence of risk alleles associated with RDS]; as well as their psychosocial traits (questionnaires). BMI changes and sociodemographic data were abstracted from Electronic Health Records. Results: Subjects showed ∆BMI (M = 10.0 ± 1.05 kg/m2) and a mean % excess weight loss (56 ± 13.8%). In addition, 76% of subjects had GARS scores above seven. The homozygote risk alleles for MAO (rs768062321) and DRD1 (rs4532) showed a 38% and 47% prevalence among the subjects. Of the 11 risk alleles identified by GARS, the DRD4 risk allele (rs1800955), was significantly correlated with change in weight and BMI six months post-surgery. We identified correlations with individual risk alleles and psychosocial trait scores. The COMT risk allele (rs4680) showed a negative correlation with EEI scores (r = -0.4983, p < 0.05) and PSQI scores (r = -0.5482, p < 0.05). The GABRB3 risk allele (rs764926719) correlated positively with EEI (r = 0.6161, p < 0.01) and FCQ scores (r = 0.6373, p < 0.01). The OPRM1 risk allele showed a positive correlation with the DERS score (r = 0.5228, p < 0.05). We also identified correlations between DERS and BMI change (r = 0.61; p < 0.01). Conclusions: These data support the potential benefit of a personalized medicinal approach inclusive of genetic testing and psychosocial trait questionnaires when counselling patients with obesity considering bariatric surgery. Future research will explore epigenetic factors that contribute to outcomes of bariatric surgery.

Overlapping and distinct relationships between hedonic hunger, uncontrolled eating, food craving, and the obesogenic home food environment during and after a 12-month behavioral weight loss program

Hedonic hunger, reward-driven eating outside of biological need, is a newer construct in eating behavior research. During behavioral weight loss (BWL), greater improvements in hedonic hunger are associated with higher weight loss, but it remains unclear if hedonic hunger predicts weight loss independent of more well-established, similar constructs (uncontrolled eating and food craving). Research also is needed to understand how hedonic hunger interacts with contextual factors (e.g., obesogenic food environment) during weight loss. Adults (N = 283) in a 12-month randomized controlled trial of BWL were weighed at 0, 12, and 24 months, and completed questionnaires assessing hedonic hunger, food craving, uncontrolled eating, and the home food environment. All variables improved at 12 and 24 months. Decreases in hedonic hunger at 12 months were associated with higher concurrent weight loss, but not when accounting for improvements in craving and uncontrolled eating. At 24 months, reduction in craving was a stronger predictor of weight loss than hedonic hunger, but improvement in hedonic hunger was a stronger predictor of weight loss than change in uncontrolled eating. Changes to the obesogenic home food environment failed to predict weight loss, regardless of levels of hedonic hunger. This study adds novel information on the individual and contextual factors associated with short- and long-term weight control, which can help refine conceptual models and treatment strategies.

Brain responses to food viewing in women during pregnancy and post partum and their relationship with metabolic health: study protocol for the FOODY Brain Study, a prospective observational study

INTRODUCTION

Food cravings are common in pregnancy and along with emotional eating and eating in the absence of hunger, they are associated with excessive weight gain and adverse effects on metabolic health including gestational diabetes mellitus (GDM). Women with GDM also show poorer mental health, which further can contribute to dysregulated eating behaviour. Food cravings can lead to greater activity in brain centres known to be involved in food 'wanting' and reward valuation as well as emotional eating. They are also related to gestational weight gain. Thus, there is a great need to link implicit brain responses to food with explicit measures of food intake behaviour, especially in the perinatal period. The aim of this study is to investigate the spatiotemporal brain dynamics to visual presentations of food in women during pregnancy and in the post partum, and link these brain responses to the eating behaviour and metabolic health outcomes in women with and without GDM.

METHODS AND ANALYSIS

This prospective observational study will include 20 women with and 20 without GDM, that have valid data for the primary outcomes. Data will be assessed at 24-36 weeks gestational age and at 6 months post partum. The primary outcomes are brain responses to food pictures of varying carbohydrate and fat content during pregnancy and in the post partum using electroencephalography. Secondary outcomes including depressive symptoms, current mood and eating behaviours will be assessed with questionnaires, objective eating behaviours will be measured using Auracle and stress will be measured with heart rate and heart rate variability (Actiheart). Other secondary outcome measures include body composition and glycaemic control parameters.

ETHICS AND DISSEMINATION

The Human Research Ethics Committee of the Canton de Vaud approved the study protocol (2021-01976). Study results will be presented at public and scientific conferences and in peer-reviewed journals.

Healthy cravings? Impact of imagined healthy food consumption on craving for healthy foods and motivation to eat healthily - Results of an initial experimental study

Craving for high-calorie foods predicts consumption of high-calorie foods thereby contributing to unhealthy eating habits and, potentially in the long term, to the development of overweight, obesity, and eating disorder pathology. Thus, effective interventions tackling craving for unhealthy foods and motivating healthy eating behavior are needed. This initial study tested if an experimental mental imagery procedure could induce craving for healthy foods and increase the motivation to eat healthily. Participants (N = 82) were randomized to either a healthy craving mental imagery condition or to a neutral mental imagery control condition. Craving for healthy foods and motivation to eat healthily was assessed before and after the experimental manipulation via self-report. A (disguised) food choice for healthy versus unhealthy food was added as a behavioural measure at the end of the experiment. Repeated measures of variance analyses with time (pre vs. post experimental manipulation) and condition (healthy craving mental imagery versus neutral mental imagery) yielded significant interactions for healthy craving and motivation to eat healthily: Post-hoc tests showed that craving for healthy foods and motivation to eat healthily increased significantly after the experimental manipulation in the healthy craving mental imagery condition, but not in the neutral mental imagery condition. Results of this initial study suggest that an experimental mental imagery induction of craving for healthy food leads to an increase in healthy craving and motivation to eat healthily. Further experimental research is needed to rule out priming effects, to test the underlying mechanisms of this effect, and evaluate the potential of this mental imagery procedure in a clinical context.

Modified cue exposure for adolescents with binge eating behaviour: study protocol of a randomised pilot trial called EXI(ea)T

INTRODUCTION

Binge eating (BE) behaviour is highly prevalent in adolescents, and can result in serious metabolic derangements and overweight in the long term. Weakened functioning of the behavioural inhibition system is one potential pathway leading to BE. Food cue exposure focusing on expectancy violation (CE_EV) is a short intervention for BE that has proven effective in adults but has never been tested in adolescents. Thus, the current randomised pilot trial evaluates the feasibility of CE_EV for adolescents and its efficacy in reducing eating in the absence of hunger (EAH) of binge food items.

METHODS AND ANALYSIS

The trial will include N=76 female adolescents aged between 13 and 20 years with a diagnosis of bulimia nervosa, binge eating disorder (BED) or their subthreshold forms based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Participants will be randomly assigned to two sessions of CE_EV or behavioural analysis (BA), a classical cognitive-behavioural therapy-based intervention. The primary endpoint is the change in EAH measured according to ad libitum consumption of personally preferred binge food in a bogus taste test at post-test based on the intention-to-treat population. Key secondary endpoints are changes in EAH of standardised binge food at post-test, in EAH at 3-month follow-up (FU) and in food craving after induction of food cue reactivity at post-test and FU. To identify further valid outcome parameters, we will assess effects of CE_EV compared with BA on global ED psychopathology, BE frequency within the last 28 days, body weight, response inhibition and emotion regulation abilities. Treatment groups will be compared using analysis of covariance with intervention as fixed factor and body mass index at baseline as covariate.

ETHICS AND DISSEMINATION

This clinical trial has been approved by the Ethics Review Committee of the Medical Association of Rhineland-Palatinate and the Medical Faculty of the Ruhr-University Bochum. The collected data will be disseminated locally and internationally through publications in relevant peer-reviewed journals and will be presented at scientific and clinical conferences. Participants data will only be published in an anonymised form.

TRIAL REGISTRATION NUMBER

DRKS00024009.

Real-time Assessment of the Bidirectional Relationship Between Affective States and Glucose: Protocol for a 14-Day Observational Study

BACKGROUND

Glucose variability increases cardiometabolic disease risk. While many factors can influence glucose levels, postprandial glucose response is the primary driver of glucose variability. Furthermore, affect may directly and indirectly impact glucose variability through its effect on eating behavior. Continuous glucose monitors (CGMs) facilitate the real-time evaluation of blood glucose, and ecological momentary assessment (EMA) can be used to assess affect in real time. Together, data collected from these sources provide the opportunity to further understand the role of affect in glucose levels.

OBJECTIVE

This paper presents the protocol for a study that aims to (1) evaluate the feasibility and acceptability of using CGMs along with EMA in nondiabetic populations and (2) examine the bidirectional relationship between affect and glucose in nondiabetic adults with overweight or obesity using a CGM and EMA.

METHODS

Eligibility criteria for the study include participants (1) aged 18 to 65 years old, (2) with a BMI of ≥25 kg/m², (3) who are able to read and write in English, and (4) who own a smartphone. Individuals will be excluded if they (1) have type 1 or 2 diabetes or have any other condition that requires glucose monitoring, (2) are pregnant, (3) use any medications that have the potential to alter blood glucose levels or interfere with the glucose sensing process, or (4) have a diagnosed gastrointestinal condition or eating disorder. In a 14-day observational study, participants will wear a FreeStyle Libre Pro CGM sensor (Abbott) and will receive mobile phone-based EMA prompts 6 times per day (randomly within six 2-hour windows between 8 AM and 8 PM) to assess positive and negative affect. Participants will also wear a Fitbit Inspire 2 (Fitbit) to continuously monitor physical activity and sleep, which will be included as covariates in the analysis. Multilevel linear regression models will be used to evaluate the acute relationship between glucose level and affect.

RESULTS

Recruitment started in October 2022 and is expected to be completed in March 2023. We will aim to recruit 100 participants. As of December 12, 2022, a total of 39 participants have been enrolled.

CONCLUSIONS

The results of this study will further elucidate the role of affect in glucose variability. By identifying affective states that may lead to glucose excursions, our findings could inform just-in-time behavioral interventions by indicating opportunities for intervention delivery.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/45104.

Reactivity to food cues in spicy food cravers: Physiological and behavioral responses

In China, the rate of spicy food consumption is rising, and chili pepper is among the most popular spicy foods consumed nationwide. According to the 'cued overeating' model, visual and olfactory cues of food can lead to changes in physiological responses and increase the likelihood and amount of food intake. However, no studies have explored the role of spicy food cues in cue reactivity among spicy food cravers. The exploratory study aimed to investigate cue-induced physiological responses, subjective cravings, eating behaviors and their associations in spicy food cravers. A group of spicy cravers (n = 59) and a group of age- and sex-matched non-cravers (n = 60) were exposed to food cues that contained or did not contain chili, during which physiological responses and food consumption were measured. The results revealed that spicy food cravers showed increased salivation and heart rate in response to food cues that contained chili compared to cues without chili and consumed significantly more chili oil after chili exposure. For cravers, heart rate during chili exposure was positively correlated with changes in subjective spicy food craving, and increases in subjective spicy food craving during chili exposure positively predicted subsequent chili oil consumption. The current exploratory study confirms the 'cued overeating' model and extends previous findings on food cravings, showing that even though chili peppers can elicit aversive oral burns and pain, they share the same physiological mechanism underlying cue reactivity as other kinds of cravings.

Long-term effects of imaginal retraining in overweight and obesity: A controlled study

BACKGROUND

Imaginal retraining (IR) is a self-help technique that targets automatic approach tendencies toward appetitive stimuli. In a randomized controlled trial (RCT; N = 384), IR reduced craving for high-calorie foods after a six-week intervention period (small effect). The aim of the present study was to evaluate long-term effects of IR in this sample.

METHODS

One year after baseline, participants from the initial RCT were recontacted. A visual analogue scale measuring craving, the Food Cravings Questionnaire-Trait-reduced (FCQ-T-r), the Three-Factor Eating Questionnaire, the Beck Depression Inventory, quality of life, and subjective appraisal of the intervention were assessed online. Participants were classified as users or nonusers based on self-reported usage of IR over the previous year.

RESULTS

Linear-mixed models showed no significant interaction effects of time and group for any outcome (trend level effects were found for two subscales of the FCQ-T-r). Yet, higher usage of IR was associated with greater symptom reduction. Although overall subjective appraisal of the intervention was comparably good to the initial study, usage of IR and completion rate were unsatisfactory.

LIMITATIONS

Main limitations of the present study include the nonrandomized group allocation and the low completion rate.

CONCLUSIONS

This study did not find evidence for the long-term efficacy of IR in individuals with craving for high-calorie foods. Only upon high usage of IR, improvement was found. However, low completion rate and usage of the intervention may have resulted in a Type-II error. Future studies may consider low-intensity professional guidance to increase adherence and assess the long-term effects of IR in RCTs.

Imaginal retraining reduces craving for high-calorie food

Imaginal retraining (IR) is a treatment derived from approach bias modification to reduce strong craving for high-calorie food. The push component (IR_push) seems to be the most effective element according to a recent dismantling trial. Conclusions derived from prior studies are limited, however, by small sample sizes and restriction of participants to women. The present study aimed to overcome these limitations and also tested a new variant of IR (3P; decoupling with the elements pull, pause, push), which has previously been found to be more effective than the standard protocol in individuals with problematic alcohol use. The study was conducted online. A total of 1,106 participants with strong craving for high-calorie food were randomized to different brief interventions of IR or a passive control group. Before and after the interventions, participants indicated their craving for high-calorie food and appraised food pictures. The main conditions of interest were IR_push and 3P. The other two experimental conditions did not contain a motor element and served as active control conditions. IR_push proved the most effective intervention and reduced craving by approximately 18%, which was significantly larger than in the passive control group. IR_push worked especially well for those with higher initial weight, higher cravings, and more dysfunctional eating behavior. The novel 3P technique significantly reduced craving across time and was especially effective for those with high BMI and craving. The study suggests that a simple self-help component of imaginal retraining, IR_push, can decrease craving for high-calorie food to a relevant extent. Future trials should elucidate whether different forms of substance-related and behavioral addictions require adapted IR or 3P protocols to increase effectiveness.

Taking Placebos as Needed to Reduce Appetite: A Randomized Controlled Trial with Ecological Momentary Assessment

Placebos can reduce appetite. However, when placebos are prescribed over a longer period of time, compliance and response rates are not always satisfactory. A new administration approach ‘as needed’ was tested to improve adherence to placebo treatment and its effectiveness. Participants could decide on the time of placebo intake (when their appetite had increased substantially). A randomized controlled trial was conducted over seven days. The participants were allocated to one of two groups: a placebo group (PG; n = 41) or a control group with no placebo treatment (CG; n = 34). During the intervention, participants used a mobile phone application to rate their daily appetite, mood, and the occurrence of binge-eating episodes in their normal environment. The placebo effect was short-lived; the placebo reduced self-reported appetite only on days 1 and 2 of the trial. The placebo neither influenced mood nor binge-eating frequency. This study found an app-assisted approach with continuous monitoring to be helpful for identifying the temporal course of the placebo response. Future placebo trials should implement this method.

Body shape perception in men and women without obesity during caloric restriction: a secondary analysis from the CALERIE study

OBJECTIVE

To examine body shape perception in 218 adults without obesity or history of eating disorders during caloric restriction (CR).

METHODS

Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) is a 2-year, randomized clinical trial using a 2:1 assignment (CR, 25% reduction in calories; Control, typical diet). For this secondary analysis, we examined perceived body shape using the Body Shape Questionnaire (BSQ). Analyses of BSQ scores are reported by group, over time, by sex, and by BMI. Data for body fat percentage, symptoms of depression, food cravings, maximal oxygen consumption, and stress were analyzed for their association with BSQ scores.

RESULTS

Compared to control, CR reduced BSQ scores. Women tended to have greater concern with body shape than men across all measurement times. There was no difference in change in BSQ scores at 12 or 24 months between those with a BMI < 25 kg/m² or ≥ 25 kg/m². Change in body fat percentage was most correlated with change in BSQ score from 0 to 12 (r = 0.39) and 0-24 months (r = 0.38). For change in BSQ score, Akaike/ Bayesian information criterion (AIC/BIC) found that the model of best fit included the following three change predictors: change in body fat percentage, depression symptoms, and food cravings. For 0-12 months, AIC/BIC = 1482.0/1505.6 and for 0-24 months AIC/BIC = 1364.8/1386.5.

CONCLUSIONS

CR is associated with reduced concern for body shape in men and women without obesity and with no history of eating disorders. Body shape perception among this sample was complex and influenced by multiple factors.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Emotional Eating Interventions for Adults Living with Overweight or Obesity: A Systematic Review and Meta-Analysis

BACKGROUND

Emotional eating (EE) may be defined as a tendency to eat in response to negative emotions and energy-dense and palatable foods, and is common amongst adults with overweight or obesity. There is limited evidence regarding the effectiveness of interventions that address EE.

OBJECTIVES

To synthesize evidence on the effectiveness of EE interventions for weight loss and EE in adults living with overweight or obesity.

METHODS

This is a systematic review and meta-analysis. Adhering to the PRISMA guidance, a comprehensive electronic search was completed up to February 2022. Random effects meta-analysis was carried out to determine the percentage change in weight and EE scores.

RESULTS

Thirty-four studies were included. The combined effect size for percentage weight change was -1.08% (95% CI: -1.66 to -0.49, I² = 64.65%, n = 37), once adjusted for publication bias. Similarly, the combined effect size for percentage change in EE was -2.37%, (95% CI: -3.76 to -0.99, I² = 87.77%, n = 46). Cognitive Behavioural Therapy showed the most promise for reducing weight and improving EE.

CONCLUSIONS

Interventions to address EE showed promise in reducing EE and promoted a small amount of weight loss in adults living with overweight or obesity.

Tasting inhibition: A proof-of-concept study of the food stop-signal game

Self-Control is an important skill in everyday life when attention is automatically drawn toward certain stimuli. For instance, food stimuli automatically capture visual attention and are processed preferentially. Therefore, efficient response inhibition is crucial to refrain from careless overeating. In the present proof-of-concept study we use a novel adaptation of a previously evaluated Stop-Signal Game (SSG) to measure reactive, food-specific, response inhibition in healthy adults. We analyzed a sample of 83 participants (60 female, mean age=24.1, mean BMI=21.71kg/m2) split into three groups. In a gamified stop-signal task, participants navigated an avatar in an urban environment toward high-calorie food, low-calorie food, or non-food stimuli in go-trials and were asked to inhibit the approach reaction in stop-trials. Hunger, eating styles, food craving, and impulsivity were assessed via self-reports to investigate their relationship with (food-specific) response inhibition. Results showed that response inhibition (in terms of stop-signal reaction time, SSRT) did not differ between the high-calorie, low-calorie, and non-food SSG which might be explained by characteristics of the sample. However, impulsivity was positively correlated with SSRT in the low-calorie SSG, whereas food-craving and hunger were positively related to response inhibition in the high-calorie SSG. Future studies could build upon the food SSG to measure and train food-specific response inhibition in the treatment of overeating.

Differential Orbitofrontal Cortex Responses to Chocolate Images While Performing an Approach-Avoidance Task in the MRI Environment

Background: Chocolate is one of the most frequently craved foods, and it often challenges self-regulation. These cravings may be underpinned by a neural facilitation of approach behavior toward chocolate. This preregistered study investigated the behavioral and neural correlates of such a bias using functional magnetic resonance imaging (fMRI) and reaction times (RTs). Methods: A total of n = 30 frequent chocolate eaters performed a relevant-feature approach-avoidance task (AAT) in the MRI scanner using buttons to enlarge (approach) or to shrink (avoid) pictures of chocolate and inedible control objects. We tested (a) whether implicit RT-based approach biases could be measured in a supine position in the scanner, (b) whether those biases were associated with activity in reward-related brain regions such as the insula, amygdala, striatum, and orbitofrontal cortex (OFC), and (c) whether individual RT-based bias-scores correlated with measures of chocolate craving. Results: Behaviorally, we found a highly reliable approach bias toward chocolate, defined by faster RTs in the compatible conditions (approach chocolate, avoid objects) compared to the incompatible conditions (avoid chocolate, approach objects). Neurally, this compatibility effect involved activity in the left medial OFC, a neural response that was positively correlated with individual approach bias scores. Conclusions: This study shows that the relevant feature AAT can be implemented in an fMRI setting in a supine position using buttons. An approach bias toward chocolate seems related to medial OFC activation that might serve to devalue chocolate when it has to be avoided. Our demonstration of neural and behavioral approach biases for chocolate underscores the need for stimulus-specific cognitive trainings to support healthy consumption and successful self-regulation.

Hypothalamic integrity is necessary for sustained weight loss after bariatric surgery: A prospective, cross-sectional study

OBJECTIVE

The hypothalamus is the main integrator of peripheral and central signals in the control of energy homeostasis. Its functional relevance for the effectivity of bariatric surgery is not entirely elucidated. Studying the effects of bariatric surgery in patients with hypothalamic damage might provide insight.

SUMMARY BACKGROUND DATA

Prospective study to analyze the effects of bariatric surgery in patients with hypothalamic obesity (HO) vs. matched patients with common obesity (CO) with and without bariatric surgery.

METHODS

65 participants were included (HO-surgery: n = 8, HO-control: n = 10, CO-surgery: n = 12, CO-control: n = 12, Lean-control: n = 23). Body weight, levels of anorexic hormones, gut microbiota, as well as subjective well-being/health status, eating behavior, and brain activity (via functional MRI) were evaluated.

RESULTS

Patients with HO lost significantly less weight after bariatric surgery than CO-participants (total body weight loss %: 5.5 % vs. 26.2 %, p = 0.0004). After a mixed meal, satiety and abdominal fullness tended to be lowest in HO-surgery and did not correlate with levels of GLP-1 or PYY. Levels of PYY (11,151 ± 1667 pmol/l/h vs. 8099 ± 1235 pmol/l/h, p = 0.028) and GLP-1 (20,975 ± 2893 pmol/l/h vs. 13,060 ± 2357 pmol/l/h, p = 0.009) were significantly higher in the HO-surgery vs. CO-surgery group. Abundance of Enterobacteriaceae and Streptococcus was increased in feces of HO and CO after bariatric surgery. Comparing HO patients with lean-controls revealed an increased activation in insula and cerebellum to viewing high-caloric foods in left insula and cerebellum in fMRI.

CONCLUSIONS

Hypothalamic integrity is necessary for the effectiveness of bariatric surgery in humans. Peripheral changes after bariatric surgery are not sufficient to induce satiety and long-term weight loss in patients with hypothalamic damage.

The relationships between social media exposure, food craving, cognitive impulsivity and cognitive restraint

BACKGROUND

Young adults are increasingly exposed to social media and their image/video-based activities. They use these platforms to share images, videos and advice in different fields like food and nutrition with: recipe ideas, nutritional opinions or specific diets. Along with the rise of digital technologies, the prevalence of eating disorders in young adults continues to grow. The present study analyzes the psychological and eating processes through which exposure to social media may lead to the development of food craving and problematic eating behaviors.

METHODS

A total of 103 young adult men (n = 15) and women (n = 88) answered questionnaires measuring their impulsivity (Barratt Impulsiveness Scale), eating habits (Three-Factor Eating Questionnaire), food craving (Food Cravings Questionnaire-Trait-reduced), and time exposure to social media.

RESULTS

The results showed two significant serial mediations. We found a correlational link between time exposure to social media and food craving scores. This positive relation is indirectly mediated by cognitive impulsivity. We also found a positive correlation between cognitive impulsivity and food craving scores that was mediated by cognitive restraint.

CONCLUSION

A better understanding of the existing links between social media, food craving and eating behaviors such as cognitive restraint could help researchers and clinicians to better guide young adults in their use and appropriation of social media food contents.

How to pin a compulsive behavior down: A systematic review and conceptual synthesis of compulsivity-sensitive items in measures of behavioral addiction

Experimental models identify the transition from choice to compulsivity as the main mechanism underlying addiction. In behavioral addictions research, however, the adjective compulsive is used to describe virtually any kind of excessive or dysregulated behavior, which hinders the connection between experimental and clinical models. In this systematic review, we adopted a preliminary definition of compulsive behavior based on previous theoretical work. Subsequently, a systematic review following PRISMA guidelines was conducted (a) to identify the validated instruments, currently used in behavioral addictions research, that include items that are sensitive (intendedly or not) to compulsivity, and (b) to categorize those items into differentiable operationalizations of compulsivity. Six operationalizations of compulsivity emerged from item content analysis: 1. Automatic or habitual behavior occurring in absence of conscious instrumental goals; 2. Behavior insensitive to negative consequences despite conscious awareness of them; 3. Overwhelming urge or desire that impels the individual to initiate the activity and jeopardizes control attempts; 4. Bingeing, or inability to stop or interrupt the activity once initiated, resulting in an episode substantially longer or more intense than intended; 5. Attentional capture and cognitive hijacking; and 6. Inflexible rules, stereotyped behaviors, and rituals related to task completion or execution. Subsequently, a list of 15 representative items per operationalization was elaborated for independent assessment and identification of delimitation problems. A high degree of agreement was reached in assessing them as instantiating compulsivity, as well as in their assignment to the corresponding categories. However, many of them were also considered overinclusive, i.e., uncapable of distinguishing compulsivity from value-based momentary choice. To increase their discriminative value, items in future compulsivity scales should be refined to explicitly mention disconnection between behavior and declarative goals. Further research on factorial structure of a pool of items derived from these operational definitions is warranted. Such a factorial structure could be used as an intermediate link between specific behavioral items and explanatory psychobiological, learning, and cognitive mechanisms.

The effects of prefrontal vs. parietal cortex transcranial direct current stimulation on craving, inhibition, and measures of self-esteem

While prefrontal cortex dysfunction has been implicated in high food cravings, other cortical regions, like the parietal cortex, are potentially also involved in regulating craving. This study explored the effects of stimulating the inferior parietal lobule (IPL) and dorsolateral prefrontal cortex (DLPFC) on food craving state and trait. Transcranial direct current stimulation (tDCS) was administered at 1.5 mA for 5 consecutive days. Participants received 20 min of IPL, DLPFC, or sham stimulation (SHAM) each day which consisted of two rounds of 10-min stimulation, divided by a 10-min mindfulness task break. In addition, we studied inhibition and subjective psychological aspects like body image and self-esteem state and trait. To decompose immediate and cumulative effects, we measured the following on days 1 and 5: inhibition through the Go/No-go task; and food craving, self-esteem, and body appreciation through a battery of questionnaires. We found that false alarm errors decreased in the participants receiving active stimulation in the DLPFC (DLPFC-group). In contrast, false alarm errors increased in participants receiving active stimulation in the IPL (IPL-group). At the same time, no change was found in the participants receiving SHAM (SHAM-group). There was a trending reduction in craving trait in all groups. Momentary craving was decreased in the DLPFC-group and increased in IPL-group, yet a statistical difference was not reached. According to time and baseline, self-esteem and body perception improved in the IPL-group. Furthermore, self-esteem trait significantly improved over time in the DLPFC-group and IPL-group. These preliminary results indicate that tDCS modulates inhibition in frontoparietal areas with opposite effects, enhancing it in DLPFC and impairing it in IPL. Moreover, craving is moderately linked to inhibition, self-esteem, and body appreciation which seem not to be affected by neuromodulation but may rely instead on broader regions as more complex constructs. Finally, the fractionated protocol can effectively influence inhibition with milder effects on other constructs.