Overlap of food addiction and substance use disorders definitions: analysis of animal and human studies

Psychosocial risk and protective factors for youth problem behavior are associated with food addiction in the Generation Z

Objective

Food Addiction (FA) and other well-known risk behavior as substance misuse tend to co-occur and may share similar risk and protective factors. The aim of this study was to assess the association between the diagnosis/severity of FA and psychosocial domains typically related to risk behavior syndrome in a large, nationally representative community sample of Generation Z underage Italian students.

Method

The sample consisted of 8,755 students (3,623 from middle schools, 5,132 from high schools). A short version of the Yale Food Addiction Scale 2.0 was administered to evaluate FA. Risk and protective factors related to demographic, personality, behavior, and family variables were examined. Stepwise multivariate logistic and linear regressions were conducted.

Results

The prevalence of FA was 30.8%. Female gender, social anxiety and depression symptoms, social withdrawal risk, Internet gaming disorder, social media addiction, current substance use, social challenge engagement and experienced doxing boosted the chance of FA diagnosis, whereas eating fruit and vegetables, playing competitive sports and an average sleep duration of 7-8 h per night reduced these odds. FA severity was significantly and positively associated with trait impulsiveness, social anxiety and depressive symptoms, risk of social withdrawal, recent substance use, social media, and gaming addiction, doxing suffered and risky social challenges participation. Negative associations between the severity of FA and fruit and vegetable diet habits were found.

Conclusion

Our findings confirm that FA is widespread among Italian adolescents. The associations between the diagnosis and severity of FA and psychosocial risk factors for health, including, addictive and deviant behaviors related to digital misuse, suggest its belonging to the risk behavior constellation. Health promotion schemes based on a multicomponent strategy of intervention should consider the inclusion of FA and its psychosocial correlates.

Early introduction of ultra-processed foods is associated with overweight and anaemia in socially vulnerable Brazilian children

This study aimed to evaluate the early introduction of ultra-processed foods (UPF) and identify its association with overweight and anaemia in Brazilian children living in a situation of social vulnerability. A population-based cross-sectional study was conducted in a Brazilian capital. Children aged 12-59 months were included. The presence of overweight and anaemia was evaluated, as well as the introduction of twelve different UPF in children's first year of life. Association analysis was performed using Poisson regression, with robust estimates of variances. A total of 561 children were studied; 85·5 % had consumed at least one UPF evaluated in the first year of life; 19·1 % were overweight and 52·0 % were anaemic. Adjusted multivariate analyses identified that the early introduction of soft drinks (Prevalence Ratio (PR) = 1·18, 95 % CI (1·02, 1·38)), packaged snacks (PR = 1·17, 95 % CI (1·05, 1·30)) and powdered soft drinks (PR = 1·36, 95 % CI (1·16, 1·60)) increased the likelihood of children being overweight, and the early introduction of chocolate drink (PR = 1·25, 95 % CI (1·02, 1·53)) increased the likelihood of them being anaemic, when comparing children who consumed these UPF before reaching 1 year of age with those who consumed these foods at 12 months of age or older. From the results found, one can see the existing relationship between the early introduction of UPF with overweight and anaemia, being necessary to intensify public health policies to combat malnutrition, focusing on the promotion of proper and healthy eating, especially during the phase of food introduction, focusing on the population living in socially vulnerable situations.

Nutritional status changes in the treatment of substance use disorder: Relationship with substance craving

Tailored nutrition counseling enhances the efficacy of routine treatment for substance (alcohol/drugs) use disorders (SUDs). For this purpose, it is important to understand the current nutritional status of addicts and the changes in their nutritional status during the treatment process. Furthermore, the consumption of sweets to manage substance cravings is common among people with SUDs, but the evidence for the effectiveness of this practice is limited and conflicting. We therefore hypothesized SUD treatment would be associated with increases in appetite, nutrient intake, and anthropometric measurements in addicts, and that these changes, including changes in sweet consumption, would not be associated with decreased substance craving. Data for this prospective observational study were collected from 38 adult male patients who completed 21 days of inpatient SUD treatment. During the treatment, the participants' levels of appetite (P < 1.0 × 10-4), the frequency of main meals (P < 1.0 × 10-4), intake of macro- and micronutrients (P < .05 for each), and anthropometric measurements (P ≤ 5.9 × 10-4), significantly increased. Furthermore, it was found that the patients had a significant increase in sweets craving (P < 1.0 × 10-4) and sweets consumption (P = 1.2 × 10-3) during treatment. However, there was no significant difference between the individuals whose craving decreased and those whose craving did not decrease at the end of the treatment (P > .05 for both). The findings suggest the need to offer dietary counseling to individuals undergoing inpatient SUD treatment, given the substantial changes in nutritional status, and that increased consumption of sweets is not an effective strategy to reduce substance craving.

Food Addiction and Grazing-The Role of Difficulties in Emotion Regulation and Negative Urgency in University Students

University students are a vulnerable population to the development of disordered eating, such as food addiction (FA) and grazing. FA is an emerging concept characterized by an intense desire to eat hyper-palatable foods. Grazing is characterized by the repetitive and unplanned ingestion of food throughout a period of time. Both FA and grazing have been associated with increased scores of negative urgency (NU) and difficulties in emotion regulation (ER). This study aims to evaluate the frequency of FA and grazing in a university population and to test the direct, total, and indirect effects-via FA-of ER and NU on repetitive eating and compulsive grazing. A total of 338 participants responded to a set of psychological measures assessing these variables. Thirty-six (10.7%) participants met the criteria for FA diagnosis and 184 (54.4%) presented grazing. Confirmatory factor analysis showed acceptable fit indexes for the model tested (χ2(1695) = 3167.575; p < 0.001; CFI = 0.955; NFI = 0.908; TLI = 0.953; SRMR = 0.085; RMSEA = 0.051; CI 90% (0.048; 0.053); P[RMSEA ≤ 0.05] = 0.318) and suggested that FA partially mediated the effect of difficulties in ER and NU on grazing, specifically on compulsive grazing. The results indicate that individuals with difficulties in ER and impulse control under negative emotions are more likely to engage in grazing if food addiction scores are higher. These results highlight the importance of assessing these variables, particularly in at-risk populations such as university students.

Linking drug and food addiction: an overview of the shared neural circuits and behavioral phenotype

Despite a lack of agreement on its definition and inclusion as a specific diagnosable disturbance, the food addiction construct is supported by several neurobiological and behavioral clinical and preclinical findings. Recognizing food addiction is critical to understanding how and why it manifests. In this overview, we focused on those as follows: 1. the hyperpalatable food effects in food addiction development; 2. specific brain regions involved in both food and drug addiction; and 3. animal models highlighting commonalities between substance use disorders and food addiction. Although results collected through animal studies emerged from protocols differing in several ways, they clearly highlight commonalities in behavioral manifestations and neurobiological alterations between substance use disorders and food addiction characteristics. To develop improved food addiction models, this heterogeneity should be acknowledged and embraced so that research can systematically investigate the role of specific variables in the development of the different behavioral features of addiction-like behavior in preclinical models.

Treating Binge Eating Disorder With Physical Exercise: A Systematic Review and Meta-analysis

OBJECTIVE

This review aimed to collect evidence about the effectiveness of exercise programs for managing binge eating disorder (BED) (recurrent binge eating episodes).

METHODS

Meta-analysis was developed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Articles were searched in PubMed, Scopus, Web of Science, and Cochrane Library. Randomized controlled trials were eligible for inclusion if they reported the effect of an exercise-based program on BED symptoms in adults. Outcomes were changes in binge eating symptom severity, measured through validated assessment instruments, after an exercise-based intervention. Study results were pooled using the Bayesian model averaging for random and fixed effects meta-analysis.

RESULTS

Of 2,757 studies, 5 trials were included, with 264 participants. The mean age was 44.7 ± 8.1 years for the intervention group and 46.6 ± 8.5 years for the control group. All participants were female. A significant improvement was observed between groups (standardized mean difference, 0.94; 95% credibility interval, -1.46 to -0.31). Patients obtained significant improvements either following supervised exercise programs or home-based exercise prescriptions.

IMPLICATIONS FOR RESEARCH AND PRACTICE

These findings suggest that physical exercise, within a multidisciplinary clinical and psychotherapeutic approach, may be an effective intervention for managing BED symptoms. Further comparative studies are needed to clarify which exercise modality is associated with greater clinical benefits.

Eating Compulsivity in Inpatients with Severe Obesity and the General Population: The Italian Version of the Measure of Eating Compulsivity (MEC10-IT)

This study aimed to validate and investigate the psychometric properties of the Italian version of the Measure of Eating Compulsivity-10 (MEC10-IT) in a sample of inpatients with severe obesity (Study 1), and to test the measurement invariance of the measure across non-clinical and clinical samples (Study 2). In the first study, a confirmatory factorial analysis (CFA) was conducted among 452 patients in order to confirm the factorial structure of the MEC10-IT. In the second study, the psychometric properties of the MEC10-IT were tested on 453 inpatients with severe obesity and a community sample of 311 participants. The CFA confirmed the factorial structure of the MEC10-IT among an Italian sample of adult inpatients with severe obesity (Study 1). The MEC10-IT was also demonstrated to be invariant between the clinical and the community sample and to possess good psychometric properties, as well as excellent screening abilities for classifying individuals with problematic eating behaviors (Study 2). In conclusion, the MEC10-IT could be considered as a valid and reliable tool for the assessment of compulsive eating in both non-clinical and clinical samples and represents a psychometrically sound measure for clinical and research purposes.

Sex-dependent role of orexin deficiency in feeding behavior and affective state of mice following intermittent access to a Western diet - Implications for binge-like eating behavior

Binge eating disorder is a debilitating disease characterized by recurrent episodes of excessive food consumption and associated with psychiatric comorbidities. Despite a growing body of research investigating the neurobiological underpinnings of eating disorders, specific treatments are lacking. Given its fundamental role in feeding behaviors, we investigated the role of the orexin (hypocretin) neuropeptide system in binge-like eating and associated phenotypes. Specifically, we submitted female and male orexin-deficient mice to a paradigm of intermittent access (once weekly for 24 h) to a Western diet (WD) to induce binge-like eating. Additionally, we measured their anxiety-like behavior and plasma corticosterone levels. All mice showed binge-like eating in response to the intermittent WD access, but females did so to a greater extent than males. While orexin deficiency did not affect binge-like eating in this paradigm, we found that female orexin-deficient mice generally weighed more, and they expressed increased hypophagia and stress levels compared to wild-type mice following binge-like eating episodes. These detrimental effects of orexin deficiency were marginal or absent in males. Moreover, male wild-type mice expressed post-binge anxiety, but orexin-deficient mice did not. In conclusion, these results extend our knowledge of orexin's role in dysregulated eating and associated negative affective states, and contribute to the growing body of evidence indicating a sexual dimorphism of the orexin system. Considering that many human disorders, and especially eating disorders, have a strong sex bias, our findings further emphasize the importance of testing both female and male subjects.

Food addiction, orthorexia nervosa and dietary diversity among Bangladeshi university students: a large online survey during the COVID-19 pandemic

PURPOSE

Maladaptive eating behaviors like food addiction (FA) are common among students, and orthorexia nervosa (ON) is being evaluated as a new condition among eating disorders (EDs). Moreover, dietary diversity (DD) is recognized as an important component of a healthy diet. Thus, the current study sought to examine the prevalence of ON and FA as well as the factors associated with ON, FA, and DD among university students in Bangladesh during the COVID-19 pandemic.

METHODS

Four-thousand-and-seventy-six students were recruited and completed an online survey consisting of the Bratman Orthorexia test, the modified Yale Food Addiction Scale, and a questionnaire based on the Food and Agriculture Organizations' guidelines. Inferential statistics, bivariate and multivariable linear regression were used for analyzing data.

RESULTS

ON and FA were observed in 1.7% and 7.5% of participants, respectively, with 43.8% exhibiting Health Fanatic eating attitude. The mean DD score was 5.96 (SD = 1.56). Students with ON consumed more legumes, nuts, seeds, and vegetables including dark green leafy vegetables whereas students with FA consumed more organ meats and eggs. Students who were older-aged, married, formerly smoked, had fitness goals, and had guilty feelings about violating food rules were more likely to have ON, whereas those who were female, were married, actively smoked, and were overweight and obese were more likely to have FA.

CONCLUSIONS

The findings suggest that students from Bangladesh are at risk of FA, and less so for ON. These entities and low DD deserve more research attention in Bangladesh to increase awareness and ensure appropriate interventions.

Morphine and high-fat diet differentially alter the gut microbiota composition and metabolic function in lean versus obese mice

There are known associations between opioids, obesity, and the gut microbiome, but the molecular connection/mediation of these relationships is not understood. To better clarify the interplay of physiological, genetic, and microbial factors, this study investigated the microbiome and host inflammatory responses to chronic opioid administration in genetically obese, diet-induced obese, and lean mice. Samples of feces, urine, colon tissue, and plasma were analyzed using targeted LC-MS/MS quantification of metabolites, immunoassays of inflammatory cytokine levels, genome-resolved metagenomics, and metaproteomics. Genetic obesity, diet-induced obesity, and morphine treatment in lean mice each showed increases in distinct inflammatory cytokines. Metagenomic assembly and binning uncovered over 400 novel gut bacterial genomes and species. Morphine administration impacted the microbiome's composition and function, with the strongest effect observed in lean mice. This microbiome effect was less pronounced than either diet or genetically driven obesity. Based on inferred microbial physiology from the metaproteome datasets, a high-fat diet transitioned constituent microbes away from harvesting diet-derived nutrients and towards nutrients present in the host mucosal layer. Considered together, these results identified novel host-dependent phenotypes, differentiated the effects of genetic obesity versus diet induced obesity on gut microbiome composition and function, and showed that chronic morphine administration altered the gut microbiome.

Prevalence of food addiction using the Yale-C scale in Mexican children with overweight and obesity

Background

The prevalence of excess weight and obesity in children has increased significantly worldwide. The concept of food addiction (FA) has been associated with eating-related problems and obesity. Studies on this topic have primarily examined adult samples and little is known about addictive-like eating among Mexican children and adolescents.

Methods

We conducted this study to examinate the prevalence of FA in a group of 291 overweight and obese children and adolescents using YFAS scale for children (YFAS-C) in Mexico.

Results

According to the YFAS-C approximately 14.4% of participants met for FA diagnosis. Forty-two (14.4%) received a FA diagnosis: 14 children and 28 adolescents. The number of FA symptoms in participants who received an FA diagnosis (M = 4.35, SD = 1.07) compared to participants with no FA diagnosis (M = 1.70, SD = 1.53) was significantly higher (p ≤ 0.001). There were no statistically significant gender differences and the proportion of subjects with an FA diagnosis did not differ by age between children and adolescents. FA is a focus of interest in attempting to explain certain behaviors that may contribute to the development of obesity and explain the failure of the weight loose programs in children.

Weighing the Risk: Developmental Pathways and Processes Underlying Obesity to Substance Use in Adolescence

Research on co-occurring obesity and substance use in adolescence has grown substantially in the past decade, but questions on the pathways and processes underlying co-occurrence remain. This review first synthesizes empirical findings on the relationship between obesity and substance use (e.g., alcohol, cannabis, tobacco use). Multidisciplinary theoretical frameworks referencing behavioral medicine, neuroscience, psychology, and public health are then used to inform an interdisciplinary, conceptual model focused on pathways and processes by which obesity increases risk of substance use. Recommendations for future research underscore the importance of prospective studies that encompass multiple domains of development. Recommendations for practice include family-based interventions that promote adaptive self-regulation, targeted antibullying or victimization interventions, and increased attention by health professionals on risky behavior associated with adolescent obesity.

Substance use disorder and obesogenic eating: Does working memory training strengthen ability to abstain from unwanted behaviors? A systematic review

INTRODUCTION

Abstaining from unwanted behaviors requires a sufficient balance between the executive and impulsive cognitive systems. Working memory (WM) is a vital component of both systems, identified in a wide range of research as the central and dominant component of executive function. WM potentially modulates the desires, tendencies, and behaviors specific to and seen in individuals with substance use disorder (SUD) and obesogenic eating (OE). Compared to healthy populations, research has shown individuals with SUD, as well as those who display OE, to have some degree of executive dysfunction, and both conditions have far-reaching health care implications. Additionally, these deficits are associated with impulsive behavior. Research has proposed that impulsive and so-called reward-driven responses could be altered through cognitive therapy and that both SUD and OE could benefit from working memory training (WMT).

METHOD

In this narrative review, we systematically align extant empirical reasoning and evidence with these assumptions. Our main aim is to ascertain and summarize the value of WMT for the treatment of both SUD and food reward consummatory behaviors. As a means to include detailed narrative accounts of all papers of potential value, our thresholds for meaningful improvements in both WM and unwanted behaviors are broad.

RESULTS

The results from the eleven qualifying studies are as follows: Nine of ten studies show a significant positive training effect of WMT on one or more components of WM capacity; three of six eligible papers (two on alcohol and one on opioid addiction) deliver notable improvements in SUD in response to WMT. One of two suitable studies showed WMT to be a moderately efficacious form of therapy for OE. Conversely, WMT appears to have negligible therapeutic benefit for cognitive function deficits or psychopathology unrelated to WM, suggesting that WMT has unique treatment efficacy for impulsive human behaviors.

CONCLUSION

In conclusion, more rigorous and uniform studies on WMT and impulsive harmful behaviors are required to give proof of the benefits of this potential useful treatment.

The impact of food addiction behaviours on the treatment of overweight students

The present study evaluated the association of food addiction (FA), the change of the BMI/age z-score and the consumption of ultra-processed foods in overweight students undergoing a 16-month, multicomponent intervention in the school environment. FA was investigated using the Yale Food Addiction Scale for Children, and the dietary assessment was estimated using the semi-quantitative FFQ in overweight 9-11-year-old students (BMI/age z-score ≥ 1) of both sexes at their baseline and after the intervention (n 120). Among the schoolchildren, 33·4 % had FA in at least one of the two assessments. The analysis of mixed-effects models to assess the effect of the intervention and the change of the BMI/age z-score between evaluations showed that the occurrence of FA influenced the maintenance of weight (time#FA, β = 0·30, 95 % CI 0·05, 0·54, P = 0·016). Weight loss was observed only in individuals who did not present FA (BMI/age z-score = -0·3). When evaluating the effect of the intervention and the dietary variables, we verified a reduction in the consumption of sugary milk-based drinks -71·13 kJ (-17 kcal), P = 0·04 only in non-FA students at the end of the study. FA has been identified as an underlying factor with therapeutic relevance, and an enhanced understanding of FA can open new paths for the prevention and management of obesity.

Foods and Nutritional Characteristics Associated With Addictive-Like Eating

Emerging literature is exploring the contribution of specific nutritional characteristics and food additives to the development of addictive-like eating, implicating highly processed foods and those high in fat and sugar in its pathophysiology. To our knowledge, no mixed methods study has yet aimed to investigate the relationship between food characteristics and addictive-like eating. Towards this end, we applied an a priori classification scheme to open-ended answers to enable us to use quantitative methods to analyze qualitative data. A sample of individuals who endorsed self-perceived "food addiction" (N = 182; 50% female; M_age = 34.1) reported the foods to which they believed they were "addicted." We classified these foods according to their levels of fat, carbohydrates, sugar, and sodium, and evaluated their predictive power on addictive-like eating. Pizza, chocolate, hamburgers, and pasta respectively, were the most reported food items to which participants felt they were addicted. Addictive-like eating was significantly predicted by endorsement of "addiction" to high-sodium foods. In contrast, "addiction" to high-sugar foods negatively predicted addictive-like eating symptoms. Findings support an association between highly processed and high-sodium foods with addictive-like eating behavior among humans, consistent in large part with prior human and animal literature. Results also suggest that people are readily able to report on their experiences of addiction to foods; specifically, they can freely endorse the experience of addictive-like eating and offer experiences of addictive foods that are largely consistent with theory and the literature.

The FODRAT study (FOod addiction, DRugs, Alcohol and Tobacco): first data on food addiction prevalence among patients with addiction to drugs, tobacco and alcohol

OBJECTIVES

The main focus of this study was to evaluate the prevalence of food addiction (FA) in a population of 575 subjects, all affected by drugs, alcohol and/or tobacco addiction.

METHODS

Patients were enrolled in Addiction Service Centers and 25 items YFAS questionnaire was administered. Prevalence of FA was studied among patients who already have an addiction and then this prevalence was compared between groups of abusers (by type of substance), comparing mono abusers with polyabusers, as well as regressions by age, BMI, sex, through multiple regression analysis.

RESULTS

Prevalence of FA in the sample is 20.17%. Risk of FA increases with the number of substances used (polyabuse). Results show a positive correlation, in addicted people, between BMI values and FA, with significant values (OR 1.08; 95% CI 1.04-1.13; p = 0.006). Age is inversely correlated with FA (OR 0.97; 95% CI 0.95-0.99; p = 0.01). Female sex is positively associated (OR 2.60; 95% CI 1.59-4.27, p = 0.000). No significant association appears with any substance, even if the highest prevalence is recorded among cannabis users (31.03%), and heroin (21.07%), followed by cocaine (18.53%), alcohol (14.49%) and tobacco (11.61%). A comparison between the FA prevalence in our study and that from another study in the Italian general population (11%) shows a significant difference (p < 0.001).

CONCLUSIONS

Prevalence of FA among addicted people is greater than in the general population. Risk of FA increases with the increase in number of used substances (polyabuse). Age is inversely correlated with FA. There is a positive and significant correlation between BMI and FA among substance/tobacco abusers.

LEVEL OF EVIDENCE

Level V, observational cross-sectional descriptive study.

Associations of Body Weight and Waist Circumference with Psychopathology, Substance Use, and Well-Being in an Adult Transdiagnostic Sample

BACKGROUND

Prior studies have established inconsistent associations between body weight and mental health. However, most work has relied on body mass index (BMI) and examination of a single mental health variable. The present study examined associations of BMI and waist circumference with multiple mental health variables in a transdiagnostic psychiatric sample.

METHODS

Nursing staff measured waist circumference and calculated the BMI of 742 adults (54.6% female, 45.4% male) presenting for psychiatric treatment. Participants completed the Patient Health Questionnaire (PHQ-9), Generalized Anxiety Disorder Scale (GAD-7), Behavior and Symptom Identification Scale (BASIS-24), and Mental Health Continuum-Short Form (MHC-SF) as part of standard clinical monitoring. Suicide risk was assessed using the clinician-administered Mini International Neuropsychiatric Interview (M.I.N.I.). For curve fit estimation regression models, we entered BMI and waist circumference as independent variables separately; we entered seven dependent variables separately: 1) depression, 2) anxiety, 3) substance use, 4) self-harm, 5) interpersonal functioning, 6) well-being, and 7) suicide risk.

RESULTS

Increased BMI was associated with decreased well-being and increased depression. Increased waist circumference was associated with worse interpersonal functioning. Non-linear (quadratic) associations were observed between weight and depression, substance use, self-harm, and suicide.

LIMITATIONS

Most of the sample was White and only 2.6% was in the underweight category, limiting broad applicability of findings. Cross-sectional design precludes causal attributions.

CONCLUSIONS

Given associations between well-being, depression, interpersonal functioning, substance use, self-harm, and suicide with weight, findings may be used to inform mental health treatment, particularly by tailoring interventions to high-risk weight categories (underweight, obese) in psychiatric populations.

Breaking It Down: Investigation of Binge Eating Components in Animal Models to Enhance Translation

Binge eating (BE) is a core eating disorder behavior that is present across nearly all eating disorder diagnoses (e. g., bulimia nervosa, binge eating disorder, anorexia nervosa binge/purge subtype), and is also widely present in the general population. Despite the prevalence of BE, limited treatment options exist and there are often high rates of relapse after treatment. There is evidence showing that genetic factors contribute to the heritability of BE and support for biological contributions to BE. However, more work is needed to fully understand neurobiological mechanisms underlying BE. One approach to target this problem is to separate BE into its distinct clinical components that can be more easily modeled using pre-clinical approaches. To date, a variety of animal models for BE have been used in pre-clinical studies; but there have been challenges translating this work to human BE. Here, we review these pre-clinical approaches by breaking them down into three clinically-significant component parts (1) consumption of a large amount of food; (2) food consumption within a short period of time; and (3) loss of control over eating. We propose that this rubric identifies the most frequently used and effective ways to model components of BE behavior using pre-clinical approaches with the strongest clinical relevance. Finally, we discuss how current pre-clinical models have been integrated with techniques using targeted neurobiological approaches and propose ways to improve translation of pre-clinical work to human investigations of BE that could enhance our understanding of BE behavior.

Current Status of Evidence for a New Diagnosis: Food Addiction-A Literature Review

Food addiction is considered an important link for a better understanding of psychiatric and medical problems triggered by dysfunctions of eating behaviors, e. g., obesity, metabolic syndrome, binge eating disorder, or bulimia nervosa. At behavioral level, food addiction has high degrees of similarity with other eating disorders, a phenomenon that creates difficulties in finding specific diagnostic criteria. Food addiction has been also described as "eating addiction" or "eating dependence" by several researchers, who placed the emphasis on the behavior and not on the food itself. High-sodium foods, artificially flavored-foods, rich carbohydrate- and saturated fats-containing foods are triggers for the activation of the same neural pathways, therefore they act similarly to any drug of abuse. Food addiction is considered a disorder based on functional negative consequences, associated distress and potential risks to both psychological well-being and physical health. A clinical scale was validated for the quantification of the eating addiction severity, namely the Yale Food Addiction Severity Scale (YFAS), constructed to match DSM IV criteria for substance dependence. Using this instrument, a high prevalence of food addiction was found in the general population, up to 20% according to a meta-analytic research. The pathogenesis of this entity is still uncertain, but reward dysfunction, impulsivity and emotion dysregulation have been considered basic mechanisms that trigger both eating dysfunctions and addictive behaviors. Genetic factors may be involved in this dependence, as modulators of higher carbohydrate and saturate fat craving. Regarding the existence of potential therapeutic solutions, lorcaserin, antiepileptic drugs, opioid antagonists, antiaddictive agents are recommended for obesity and eating disorders, and they may be intuitively used in food addiction, but clinical trials are necessary to confirm their efficacy. In conclusion, a better understanding of food addiction's clinical profile and pathogenesis may help clinicians in finding prevention- and therapeutic-focused interventions in the near future.

Brain-gut-microbiome interactions in obesity and food addiction

Normal eating behaviour is coordinated by the tightly regulated balance between intestinal and extra-intestinal homeostatic and hedonic mechanisms. By contrast, food addiction is a complex, maladaptive eating behaviour that reflects alterations in brain-gut-microbiome (BGM) interactions and a shift of this balance towards hedonic mechanisms. Each component of the BGM axis has been implicated in the development of food addiction, with both brain to gut and gut to brain signalling playing a role. Early-life influences can prime the infant gut microbiome and brain for food addiction, which might be further reinforced by increased antibiotic usage and dietary patterns throughout adulthood. The ubiquitous availability and marketing of inexpensive, highly palatable and calorie-dense food can further shift this balance towards hedonic eating through both central (disruptions in dopaminergic signalling) and intestinal (vagal afferent function, metabolic endotoxaemia, systemic immune activation, changes to gut microbiome and metabolome) mechanisms. In this Review, we propose a systems biology model of BGM interactions, which incorporates published reports on food addiction, and provides novel insights into treatment targets aimed at each level of the BGM axis.

A Meta-Analysis of Transcranial Direct Current Stimulation on Substance and Food Craving: What Effect Do Modulators Have?

Substance addiction and food addiction are significant social problems worldwide. In previous studies of substance addiction, transcranial direct current stimulation (tDCS) has been used to influence craving of substance or food. However, the reported effects are not always consistent due to inconsistent experimental settings. The way modulators influence the effect of tDCS on substance addiction is worth exploring. This meta-analysis was conducted to estimate the effect size of tDCS on substance and food craving and to investigate the influence of potential modulators. We systemically identified and reviewed studies on substance/food craving using tDCS that were published between January 2008 to January 2020. A total of 32 eligible studies were identified. Hedges' g was computed as an indicator of the effect of tDCS and some potential moderators (substance type, stimulation sites, current intensities, number of sessions, duration of stimulation, and study design) were examined using subgroup analysis. Random effects analysis revealed a total medium effect size [Hedges' g = 0.536, 95% confidence interval (CI): 0.389-0.683, after adjusting Hedges' g = 0.416, 95% CI: 0.262-0.570] preferring active over sham stimulation to reduce craving. A significant difference was observed between the number of sessions (repeated stimulation was better than single stimulation). The duration of stimulation may have a positive influence on the effects of tDCS. No other significant differences were found in other subgroups analysis. In conclusion, our results provided evidence that tDCS can be an effective way to reduce craving of substance or food, and longer multiple stimulus durations in all can more effectively reduce craving; however, the influences of modulators still need be to be examined in depth in future.

Pre-clinical models of reward deficiency syndrome: A behavioral octopus

Individuals with mood disorders or with addiction, impulsivity and some personality disorders can share in common a dysfunction in how the brain perceives reward, where processing of natural endorphins or the response to exogenous dopamine stimulants is impaired. Reward Deficiency Syndrome (RDS) is a polygenic trait with implications that suggest cross-talk between different neurological systems that include the known reward pathway, neuroendocrine systems, and motivational systems. In this review we evaluate well-characterized animal models for their construct validity and as potential models for RDS. Animal models used to study substance use disorder, major depressive disorder (MDD), early life stress, immune dysregulation, attention deficit hyperactivity disorder (ADHD), post traumatic stress disorder (PTSD), compulsive gambling and compulsive eating disorders are discussed. These disorders recruit underlying reward deficiency mechanisms in multiple brain centers. Because of the widespread and remarkable array of associated/overlapping behavioral manifestations with a common root of hypodopaminergia, the basic endophenotype recognized as RDS is indeed likened to a behavioral octopus. We conclude this review with a look ahead on how these models can be used to investigate potential therapeutics that target the underlying common deficiency.

Anthocyanin Metabolites in Human Urine after the Intake of New Functional Beverages

Sugar intake abuse is directly related with the increase of metabolic diseases such as type 2 diabetes, obesity, and insulin resistance. Along this line, the development of new beverages using alternative sweeteners could help with combatting the pathophysiological disorders associated to the consumption of sugar. To provide evidence on this issue, in the present work, the bioavailability of anthocyanins was evaluated after the acute ingestion of a new maqui-citrus-based functional beverage rich in polyphenols, and supplemented with a range of sweeteners including sucrose (natural high caloric), stevia (natural non-caloric), and sucralose (artificial non-caloric), as an approach that would allow reducing the intake of sugars while providing bioactive phenolic compounds (anthocyanins). This approach allowed the evaluation of the maximum absorption and the diversity of metabolites excreted through urine. The beverages created were ingested by volunteers (n = 20) and the resulting anthocyanin metabolites in their urine were analyzed by UHPLC-ESI-MS/MS. A total of 29 degradation metabolites were detected: Caffeic acid, catechol, 3,4-dihidroxifenilacetic acid, hippuric acid, trans-ferulic acid, 2,4,6-trihydroxybenzaldehyde, trans-isoferulic acid, and vanillic acid derivatives, where peak concentrations were attained at 3.5 h after beverage intake. Sucralose was the sweetener that provided a higher bioavailability for most compounds, followed by stevia. Sucrose did not provide a remarkably higher bioavailability of any compounds in comparison with sucralose or stevia. The results propose two sweetener alternatives (sucralose and stevia) to sucrose, an overused high calorie sweetener that promotes some metabolic diseases.

Alternative Sweeteners Modify the Urinary Excretion of Flavanones Metabolites Ingested through a New Maqui-Berry Beverage

Dietary sugar has been largely related to the onset of metabolic diseases such as type 2 diabetes and obesity, among others. The growing awareness on the close relationship between the dietary habits and this health disturbance has encouraged the development of new beverages using alternative sweeteners that could contribute to combat the above referred pathophysiological disorders. To gain further insight into this issue, the present work, upon an acute dietary intervention, evaluated the urinary excretion of flavanones ingested through polyphenols-rich beverages composed of maqui berry and citrus, with the aim of establishing the highest urinary excretion rate and metabolite profiles. The functional beverages evaluated were supplemented with a range of sweeteners including sucrose (natural and high caloric), stevia (natural and non-caloric), and sucralose (artificial and non-caloric) as an approach that would allow reducing the intake of sugars and provide bioactive phenolics (flavanones). The juices developed were ingested by volunteers (n = 20) and the resulting flavanones and their phase II metabolites in urine were analyzed by Ultra-High Performance Liquid Chromatography ElectroSpray Ionization Mass Spectrometry (UHPLC-ESI-MS/MS). A total of 16 metabolites were detected: eriodyctiol, naringenin, and homoeriodyctiol derivatives, where peak concentrations were attained 3.5 h after beverage intake. Sucralose and stevia were the sweeteners that provided the highest urinary excretion for most compounds. Sucrose did not provide a remarkable higher elimination through urine of any compounds in comparison with sucralose or stevia. These results propose two alternative sweeteners to sucrose (sucralose and stevia), an overused, high caloric sweetener that promotes some metabolic diseases.

Turkish version of the Yale Food Addiction Scale: preliminary results of factorial structure, reliability, and construct validity

BACKGROUND

Yale Food Addiction Scale (YFAS) was established to identify individuals exhibiting signs of addiction towards certain types of food. This study aimed to develop a Turkish version of the Yale Food Addiction Scale and test its psychometric properties.

METHODS

The backward translation techniques were used to develop Turkish versions of the YFAS, and its reproducibility was assessed. Turkish version of the YFAS was administered to a total of 1033 participants (439 men and 594 women), aged 19-65 years. Exploratory factor analysis and confirmatory factor analysis were used to examine the factorial structure of the tool. Construct validity was assessed by principal component factor analysis with varimax rotation. Reliabilities were estimated with Cronbach's alpha coefficient. The criterion-related validity was tested by the administration of Eating Attitude Test-26 (EAT-26) to all participants.

RESULTS

The primary factor loadings for seven items were ranged between 0.45 and 0.79, and no items cross-loaded onto other factors. The fit indices showed that eight items of the YFAS were a good representation of the item responses and each item loaded significantly on the specified factor (p < 0.001 for each). YFAS subscales had a high internal consistency and test-retest reliability. The criterion-related validity of the tool showed a positive relationship with scales of the EAT-26.

CONCLUSION

Current study suggested that the Turkish version of the YFAS is a reliable, valid, and useful tool for assessing the signs of food addiction in a non-clinical sample.

Food addiction, eating addiction and eating disorders

The concept of food addiction is currently a highly debated subject within both the general public and the scientific communities. The term food addiction suggests that individuals may experience addictive-like responses to food, similar to those seen with classic substances of abuse. An increasing number of studies have established the prevalence and correlates of food addiction. Moreover, food addiction may be associated with obesity and disordered eating. Thus, intervening on food addiction may be helpful in the prevention and therapy of obesity and eating disorders. However, controversy exists about if this phenomenon is best defined through paradigms reflective of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) substance-related disorders (e.g. food addiction) or non-substance-related disorders (e.g. eating addiction) criteria. This review paper will give a brief summarisation of the current state of research on food addiction, a more precise definition of its classification, its differentiation from eating addiction and an overview on potential overlaps with eating disorders. Based on this review, there is evidence that food addiction may represent a distinct phenomenon from established eating disorders such as bulimia nervosa or binge-eating disorder. Future studies are needed to further examine and establish orthogonal diagnostic criteria specific to food addiction. Such criteria must differentiate the patterns of eating and symptoms that may be similar to those of eating disorders to further characterise food addiction and develop therapy options. To date, it is too premature to draw conclusions about the clinical significance of the concept of food addiction.

Fat Addiction: Psychological and Physiological Trajectory

Obesity has become a major public health concern worldwide due to its high social and economic burden, caused by its related comorbidities, impacting physical and mental health. Dietary fat is an important source of energy along with its rewarding and reinforcing properties. The nutritional recommendations for dietary fat vary from one country to another; however, the dietary reference intake (DRI) recommends not consuming more than 35% of total calories as fat. Food rich in fat is hyperpalatable, and is liable to be consumed in excess amounts. Food addiction as a concept has gained traction in recent years, as some aspects of addiction have been demonstrated for certain varieties of food. Fat addiction can be a diagnosable condition, which has similarities with the construct of addictive disorders, and is distinct from eating disorders or normal eating behaviors. Psychological vulnerabilities like attentional biases have been identified in individuals described to be having such addiction. Animal models have provided an opportunity to explore this concept in an experimental setting. This discussion sheds light on fat addiction, and explores its physiological and psychological implications. The discussion attempts to collate the emerging literature on addiction to fat rich diets as a prominent subset of food addiction. It aims at addressing the clinical relevance at the community level, the psychological correlates of such fat addiction, and the current physiological research directions.

Review: Non-Invasive Brain Stimulation in Behavioral Addictions: Insights from Direct Comparisons With Substance Use Disorders

BACKGROUND AND OBJECTIVES

Treatment models developed for substance use disorders (SUDs) are often applied to behavioral addictions (BAs), even though the correspondence between these forms of addiction is unclear. This is also the case for noninvasive brain stimulation (NIBS) techniques being investigated as potential treatment interventions for SUDs and BAs.

OBJECTIVES

to contribute to the development of more effective NIBS protocols for BAs.

METHODS

Two literature searches using PubMed and Google Scholar were conducted identifying a total of 35 studies. The first search identified 25 studies examining the cognitive and neurophysiological overlap between BAs and SUDs. The second search yielded 10 studies examining the effects of NIBS in BAs.

RESULTS

Impulsivity and cravings show behavioral and neurophysiologic overlaps between BAs and SUDs, however, other outcomes like working-memory abilities or striatal connectivity, differ between BAs and SUDs. The most-employed NIBS target in BAs was dorsolateral prefrontal cortex (DLPFC), which was associated with a decrease in cravings, and less frequently with a reduction of addiction severity.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Direct comparisons between BAs and SUDs revealed discrepancies between behavioral and neurophysiological outcomes, but overall, common and distinctive characteristics underlying each disorder. The lack of complete overlap between BAs and SUDs suggests that investigating the cognitive and neurophysiological features of BAs to create individual NIBS protocols that target risk-factors associated specifically with BAs, might be more effective than transferring protocols from SUDs to BAs. Individualizing NIBS protocols to target specific risk-factors associated with each BA might help to improve treatment interventions for BAs. (Am J Addict 2019;00:1-23).

Psychopathological disorders in Prader-Willi syndrome

Prader-Willi syndrome is a genetic disorder caused by chromosomal changes in segment 15q11-q13 including cognitive, mental, and behavioral symptoms, as well as a specific physical phenotype. Both the most common psychopathological changes (intellectual disability, obsessions, impulsivity, autism spectrum disorders, self-injuries) and the main psychiatric comorbidities (affective disorders, psychosis, obsessive-compulsive disorder, autism spectrum disorder) are characterized by a great heterogeneity, which warrants the need for better identification of their frequency and clinical signs. In addition to its effects on body compositionand hypotony, growth hormone has been shown to be useful for regulating patient behavior, and psychoactive drugs are also an option. Other alternatives have shown promising results in experimental trials. Adequate understanding of the psychopathology associated to Prader-Willi syndrome would allow for improving clinical approach, symptom identification, detection of comorbidities, and administration of more effective treatments, leading to better clinical outcomes.

A Critical Examination of the Practical Implications Derived from the Food Addiction Concept

PURPOSE OF REVIEW

Adopting an addiction perspective on eating disorders and obesity may have practical implications for diagnostic classification, prevention, and treatment of these disorders. The present article critically examines these implications derived from the food addiction concept.

RECENT FINDINGS

Introducing food addiction as a new disorder in diagnostic classification system seems redundant as most individuals with an addiction-like eating behavior are already covered by established eating disorder diagnoses. Food addiction may be a useful metaphor in the treatment of binge eating, but would be inappropriate for the majority of obese individuals. Implying an addiction to certain foods is not necessary when applying certain approaches inspired by the addiction field for prevention and treatment of obesity. The usefulness of abstinence models in the treatment of eating disorders and obesity needs to be rigorously tested in future studies. Some practical implications derived from the food addiction concept provide promising avenues for future research (e.g., using an addiction framework in the treatment of binge eating or applying abstinence models). For others, however, the necessity of implying an addiction to some foods needs to be scrutinized.

Prevalence of food addiction and association with stress, sleep quality and chronotype: A cross-sectional survey among university students

AIMS

Food addiction (FA) is defined as an insatiable desire for the consumption of specific high-fat, high-sugar foods beyond the required energy needs for sustenance. The aims of this study were to determine FA prevalence and to assess associations between FA, stress, sleep quality and chronotype among university students.

DESIGN AND SETTING

A cross-sectional questionnaire-based survey conducted among students from 8 major Lebanese universities. Students were randomly selected and requested to fill the questionnaire. 644 agreed to participate. Data were collected via a face-to-face interview conducted by 2 trained research assistants.

PARTICIPANTS

University students above 18 years old and not presenting any cognitive or chronic illnesses, after signing a written consent form.

MEASUREMENTS

In addition to sociodemographic data, all participants filled the following self-administered standardized and validated questionnaires: Yale Food Addiction Scale (YFAS), Perceived Stress Scale (PSS), Morningness-Eveningness Questionnaire (MEQ) and Pittsburgh Sleep Quality Index (PSQI).

FINDINGS

FA prevalence was 10.1% with a 95% confidence interval of 7.8-12.4%. 56.5% of all the participants had a poor quality of sleep, whereas 81.2% of the participants presenting FA experienced a poor sleep quality (versus 57.2% when no FA is present). 70.2% of the students presented an intermediate chronotype, 20.5% an evening chronotype and 8.7% a morning chronotype. Age, smoking status, BMI, PSS and PSQI remained significantly correlated to the continuous YFAS score in multivariate analysis.

CONCLUSIONS

Our findings denote the importance of identifying and offering help to individuals presenting a FA because it is frequent among youth, associated to higher BMI and to smoking, seems to be a very intertwined and complex phenomenon coexisting with other neuropsychiatric problems, such as stress and poor sleep quality and therefore can have serious health implications.

Environmental Enrichment During Adulthood Reduces Sucrose Binge-Like Intake in a High Drinking in the Dark Phenotype (HD) in C57BL/6J Mice

Repetitive binge episodes favor transition to binge-eating disorders. Experimental evidence points to positive influence of environmental enrichment (EE) on drug/food addiction, although far less is known regarding EE effects over binge-like consumption. Here, we evaluate the following: (1) whether switching from nonenriched standard environment (SE) to EE housing conditions during adulthood alters a stable pattern of voluntary sucrose (10% w/v) binge-like intake in high (HD) vs. low (LD) drinking phenotypes under a drinking in the dark (DID) schedule; and (2) sucrose binge-like intake in a DID task in response to a pharmacological challenge with an OXr1 antagonist in HD/LD subpopulations after long-term exposure to SE or EE conditions. Adolescent (postnatal day 21; PND21) mice were housed in SE conditions. At PND65, all animals were long-term exposed to sucrose DID. On the first episode of DID (PND65), animals were divided into HD vs. LD subpopulations according to their sucrose intake. On PND85, an OXr1 antagonist test was conducted on HD and LD mice with SB-334867 (SB) administration. On PND95, HD and LD subpopulations were again randomly allocated into two subgroups, resulting in the following experimental conditions: HD-SE, HD-EE, LD-SE and LD-EE. Sucrose binge-like intake continued until PND116, when a second SB test was conducted. The main findings are: (1) a single 2 h episode of sucrose binge drinking in a DID procedure consistently segregates two behavioral subpopulations, HD and LD; (2) when adult mice in standard conditions and long-term exposed to sucrose DID were switched to EE conditions, an immediate reduction in sucrose binge-like intake was observed in HD mice, pointing to a therapeutic role of EE exposure; and (3) administration of the OXr1 antagonist caused an acute reduction in sucrose binge-like intake in HD and LD mice exposed to SE conditions. Importantly, exposure to EE conditions blunted the inhibitory effect of SB on sucrose binge consumption in both behavioral phenotypes, indirectly suggesting a potential EE/OXr1 signaling interaction. We propose the hypothesis that EE might regulate OX-dependent anxiety/compulsivity brain systems, which might secondarily modulate sucrose binge-like intake.

Exploring the consumption of ultra-processed foods and its association with food addiction in overweight children

The present study explored the consumption of ultra-processed foods and its association with food addiction in overweight children. The prevalence of food addiction was investigated using the Yale Food Addiction Scale for Children in overweight 9-11 year-old children (BMI/age ≥1 Z score) of both sexes from two schools (n = 139). Food intake was estimated by a food frequency questionnaire and the food items were classified into 4 categories: minimally processed, culinary ingredients, processed foods and ultra-processed foods (UPF), based on their degree of processing. Among the children, 95% showed at least one of the seven symptoms of food addiction and 24% presented with a diagnosis of food addiction. In analysis of covariance adjusted for age and sex, a tendency of higher consumption of added sugar (refined sugar, honey, corn syrup) and UPF was found among those diagnosed with food addiction. Multiple logistic regression adjusted for sugar, sodium and fat ingestion showed that consumption of cookies/biscuits (OR = 4.19, p = 0.015) and sausages (OR = 11.77, p = 0.029) were independently associated with food addiction. The identification of foods that may be associated with addictive behavior is very important for correctly treating and preventing childhood obesity, which continues to be one of the greatest health problems in the world.

Dopamine genetic risk is related to food addiction and body mass through reduced reward-related ventral striatum activity

The prevalence rate of obesity continues to rise in the U.S., but effective treatment options remain elusive resulting in increased emphasis on prevention. One such area of prevention research capitalizes on the relatively novel behavioral construct of food addiction, which has been implicated in obesity. Food addiction reflects an individual's propensity for compulsive eating despite negative consequences, and shares not only symptoms with both eating and substance use disorders but also genetic and neural correlates within neural reward-circuitry modulated by dopamine. Here, we examined associations between food addiction scores, body mass index (BMI), reward-related ventral striatum activity, and a polygenic score approximating dopamine signaling in 115 non-Hispanic Caucasian young adult university students. As predicted, polygenic dopamine scores were related to ventral striatum activity, which in turn was associated with higher food addiction scores. In addition, food addiction was related to BMI. An exploratory post-hoc path analysis further indicated that polygenic scores were indirectly related to both food addiction and BMI, in part, through ventral striatum activity. Collectively, our results provide evidence supporting the utility of food addiction in weight gain prevention research by establishing links with known risk-related neural and genetic biomarkers.

What Is the Evidence for "Food Addiction?" A Systematic Review

The diagnostic construct of “food addiction” is a highly controversial subject. The current systematic review is the first to evaluate empirical studies examining the construct of “food addiction” in humans and animals. Studies were included if they were quantitative, peer-reviewed, and in the English language. The 52 identified studies (35 articles) were qualitatively assessed to determine the extent to which their findings indicated the following addiction characteristics in relation to food: brain reward dysfunction, preoccupation, risky use, impaired control, tolerance/withdrawal, social impairment, chronicity, and relapse. Each pre-defined criterion was supported by at least one study. Brain reward dysfunction and impaired control were supported by the largest number of studies (n = 21 and n = 12, respectively); whereas risky use was supported by the fewest (n = 1). Overall, findings support food addiction as a unique construct consistent with criteria for other substance use disorder diagnoses. The evidence further suggests that certain foods, particularly processed foods with added sweeteners and fats, demonstrate the greatest addictive potential. Though both behavioral and substance-related factors are implicated in the addictive process, symptoms appear to better fit criteria for substance use disorder than behavioral addiction. Future research should explore social/role impairment, preoccupation, and risky use associated with food addiction and evaluate potential interventions for prevention and treatment.

Validation of the Italian Yale Food Addiction Scale in postgraduate university students

PURPOSE

This study was aimed to examine the structural and construct validity of the Italian version of the Yale Food Addiction Scale in a multisite sample of postgraduate students.

METHODS

Two hundred and fifty-six subjects (78.1% females) aged from 18 to 53 years (mean = 23.93, SD = 4.96) and attending different postgraduate university programs at multiple Italian universities completed the Italian YFAS, the Italian Binge Eating Scale (BES), the Italian Eating Attitudes Test-26 and the Italian Dutch Eating Behavior Questionnaire (DEBQ) online through Qualtrics.

RESULTS

Confirmatory Factor Analysis showed that the single-factor model of the Italian YFAS including all original items had adequate fit indexes (χ²252 = 454.183; p < 0.001; normed χ² = 1.802; RMSEA = 0.056; 90% CI 0.048-0.076; CFI = 0.761; WRMR = 1.592). However, item analysis revealed that item#25 had zero variance (all subjects were assigned the same score after item dichotomization) and item#24 had a low factor loading, and were thus removed. Furthermore, item#10 and item#11 showed to be almost perfectly correlated (r = 0.998) and were thus parceled. The resulting 19-item single-factor model revealed a better fit to the data (χ²152 = 235.69; p < 0.001; normed χ² = 1.556; RMSEA = 0.046; 90% CI 0.034-0.058; CFI = 0.858; WRMR = 1.236) and its internal consistency was acceptable (KR-20 = 0.72). Also, a single-factor model including the seven diagnostic symptoms was tested and showed adequate fit values (χ²20 = 41.911; p < 0.003; normed χ² = 2.09; RMSEA = 0.065; 90% CI 0.037-0.093; CFI = 0.946; WRMR = 1.132). Statistically significant and small-to-high correlations were found with all convergent measures, in particular with the BES.

CONCLUSION

The Italian 19-item YFAS resulted to be a valid and reliable tool for the assessment of food addiction in postgraduate students.

LEVEL OF EVIDENCE

Level V, descriptive study.

A Systematic Review of Physical Activity Interventions in Individuals with Binge Eating Disorders

PURPOSE OF REVIEW

Our systematic review aims to assess the overall evidence available in the literature regarding the role of physical activity (PA) in individuals with binge eating disorder (BED) and better understand the potential underlying mechanisms of action.

RECENT FINDINGS

Currently, the most effective and well-established psychological treatment for BED is cognitive behavioral therapy (CBT) with a remission rate around 80%. CBT is sometimes combined with pharmacotherapy targeting comorbidities associated with BED, such as obesity and depression. Another avenue of treatment that has been less studied is PA. It has been suggested that PA addresses the underlying mechanisms of BED and, thus, increases treatment efficiency. This systematic review provides additional knowledge concerning the benefits of PA in the treatment of individuals with BED including reduction of binge eating (BE) episodes and improvement in other associated comorbidities. Potential mechanisms of action of PA include neurochemical alterations affecting the reward system, reduction of negative affect, and its anorexigenic effects.

Trace Amine Associated Receptor 1 (TAAR1) Modulation of Food Reward

Eating disorders and some forms of obesity are characterized by addictive-like, compulsive eating behavior which contains numerous similarities with compulsive drug use. Food intake is in part mediated by reward and reinforcement processes that can become dysregulated in these disorders. Additionally, impairments in inhibitory control regulation of reward-related responding can cause or further exacerbate binge and compulsive eating. Dysfunctions in two neurotransmitter systems in the mesocorticolimbic pathway, dopamine and glutamate, are thought to contribute to maladaptive eating behaviors. The trace amine associated receptor 1 (TAAR1) system is a promising therapeutic target for compulsive eating behavior due to the role of TAAR1 in synaptic transmission and in the modulation of dopaminergic and glutamatergic signaling. In support of this notion, the TAAR1 agonist RO5256390 was found to decrease the reinforcing effects of palatable food-cues and to reduce binge-like and compulsive-like eating of palatable food. Additionally, prolonged, intermittent access to palatable food was shown to downregulate TAAR1 in the prefrontal cortex, suggesting a potential role for TAAR1 signaling in inhibitory control processes. Research into the role of TAAR1 in addiction, including TAAR1’s ability to modulate psychostimulant reward and reinforcement, bolsters support for TAAR1 agonism as a pharmacological treatment for compulsive eating and other addictive behaviors. This review summarizes the evidence for TAAR1 agonism as a promising therapeutic for compulsive eating behavior as well as the hypothesized mechanism responsible for these effects.

Food Addiction and Binge Eating: Lessons Learned from Animal Models

The feeding process is required for basic life, influenced by environment cues and tightly regulated according to demands of the internal milieu by regulatory brain circuits. Although eating behaviour cannot be considered "addictive" under normal circumstances, people can become "addicted" to this behaviour, similarly to how some people are addicted to drugs. The symptoms, cravings and causes of "eating addiction" are remarkably similar to those experienced by drug addicts, and both drug-seeking behaviour as eating addiction share the same neural pathways. However, while the drug addiction process has been highly characterised, eating addiction is a nascent field. In fact, there is still a great controversy over the concept of "food addiction". This review aims to summarize the most relevant animal models of "eating addictive behaviour", emphasising binge eating disorder, that could help us to understand the neurobiological mechanisms hidden under this behaviour, and to improve the psychotherapy and pharmacological treatment in patients suffering from these pathologies.

The effect of consumption temperature on the homeostatic and hedonic responses to glucose ingestion in the hypothalamus and the reward system

Background

Excessive consumption of sugar-sweetened beverages (SSBs) has been associated with obesity and related diseases. SSBs are often consumed cold, and both the energy content and temperature might influence the consumption behavior for SSBs.

Objective

The main aim of this study was to elucidate whether consumption temperature and energy (i.e., glucose) content modulate homeostatic (hypothalamus) and reward [ventral tegmental area (VTA)] responses.

Design

Sixteen healthy men participated in our study [aged 18-25 y; body mass index (kg/m2): 20-23]. High-resolution functional magnetic resonance imaging data were collected after ingestion of 4 different study stimuli: plain tap water at room temperature (22°C), plain tap water at 0°C, a glucose-containing beverage (75 g glucose dissolved in 300 mL water) at 22°C, and a similar glucose drink at 0°C. Blood oxygen level-dependent (BOLD) changes from baseline (7 min preingestion) were analyzed over time in the hypothalamus and VTA for individual stimulus effects and for effects between stimuli.

Results

In the hypothalamus, water at 22°C led to a significantly increased BOLD response; all other stimuli resulted in a direct, significant decrease in BOLD response compared with baseline. In the VTA, a significantly decreased BOLD response compared with baseline was found after the ingestion of stimuli containing glucose at 0°C and 22°C. These responses were not significantly modulated by consumption temperature. The consumption of plain water did not have a significant VTA BOLD effect.

Conclusions

Our data show that glucose at 22°C, glucose at 0°C, and water at 0°C lowered hypothalamic activity, which is associated with increased satiation. On the contrary, the consumption of water at room temperature increased activity. All stimuli led to a similar VTA response, which suggests that all drinks elicited a similar hedonic response. Our results indicate that, in addition to glucose, the low temperature at which SSBs are often consumed also leads to a response from the hypothalamus and might strengthen the response of the VTA. This trial was registered at www.clinicaltrials.gov as NCT03181217.

Sugars, exercise and health

BACKGROUND

There is a direct link between a variety of addictions and mood states to which exercise could be relieving. Sugar addiction has been recently counted as another binge/compulsive/addictive eating behavior, differently induced, leading to a high-significant health problem. Regularly exercising at moderate intensity has been shown to efficiently and positively impact upon physiological imbalances caused by several morbid conditions, including affective disorders. Even in a wider set of physchiatric diseases, physical exercise has been prescribed as a complementary therapeutic strategy.

METHOD

A comprehensive literature search was carried out in the Cochrane Library and MEDLINE databases (search terms: sugar addiction, food craving, exercise therapy, training, physical fitness, physical activity, rehabilitation and aerobic).

RESULTS

Seeking high-sugar diets, also in a reward- or craving-addiction fashion, can generate drastic metabolic derangements, often interpolated with affective disorders, for which exercise may represent a valuable, universal, non-pharmachological barrier.

LIMITATIONS

More research in humans is needed to confirm potential exercise-mechanisms that may break the bond between sugar over-consumption and affective disorders.

CONCLUSIONS

The purpose of this review is to address the importance of physical exercise in reversing the gloomy scenario of unhealthy diets and sedentary lifestyles in our modern society.

Online effects of transcranial direct current stimulation on prefrontal metabolites in gambling disorder

Gambling disorder is characterized by persistent maladaptive gambling behaviors and is now considered among substance-related and addictive disorders. There is still unmet therapeutic need for these clinical populations, however recent advances indicate that interventions targeting the Glutamatergic/GABAergic system hold promise in reducing symptoms in substance-related and addictive disorders, including gambling disorder. There is some data indicating that transcranial direct current stimulation may hold clinical benefits in substance use disorders and modulate levels of brain metabolites including glutamate and GABA. The goal of the present work was to test whether this non-invasive neurostimulation method modulates key metabolites in gambling disorder. We conducted a sham-controlled, crossover, randomized study, blinded at two levels in order to characterize the effects of transcranial direct current stimulation over the dorsolateral prefrontal cortex on neural metabolites levels in sixteen patients with gambling disorder. Metabolite levels were measured with magnetic resonance spectroscopy from the right dorsolateral prefrontal cortex and the right striatum during active and sham stimulation. Active as compared to sham stimulation elevated prefrontal GABA levels. There were no significant changes between stimulation conditions in prefrontal glutamate + glutamine and N-acetyl Aspartate, or in striatal metabolite levels. Results also indicated positive correlations between metabolite levels during active, but not sham, stimulation and levels of risk taking, impulsivity and craving. Our findings suggest that transcranial direct current stimulation can modulate GABA levels in patients with gambling disorder which may represent an interesting future therapeutic avenue.

Evaluation of disordered eating tendencies in young adults

PURPOSE

It was aimed to determine the prevalence of high disordered eating tendencies and its relationship with food addiction, emotional eating and self esteem in participants at 18 and 33 years age group.

METHODS

This study was planned as a cross-sectional study and conducted with 1359 young adult volunteers (M = 386, F = 973) with an average age of 22.4 ± 2.84 years. Eating Attitudes Test-26 (EAT-26), Yale Food Addiction Scale (YFAS), Emotional Appetite Questionnaire (EMAQ) and Rosenberg Self-Esteem Scale (RSES) were used. EAT-26 score above 20 was considered as eating disorders risk cutoff.

RESULTS

Participants with disordered eating tendencies have higher rates (22.4%) of food addiction compared to participants without high disordered eating tendencies (7.2%). There is no difference for EMAQ and YFAS scores; however, there is a significant difference for RSES and EAT-26 scores according to gender. A positive association of EAT-26 with YFAS and EMAQ-negative scores and a negative association of EAT-26 with RSES and EMAQ-positive were found.

DISCUSSION

There is association among EAT-26, YFAS, and Rosenberg Self-Esteem Scale, and Emotional Appetite Questionnaire scores. This study provides information for future studies about high disordered eating tendencies, food addiction and mood that are thought to be important in young adults.

LEVEL OF EVIDENCE

Level V (cross-sectional descriptive study).

Assessment of the relationship between food addiction and nutritional status in schizophrenic patients

OBJECTIVE

Obesity is one of today's most important public health problems. It is suggested that overeating and substance addiction show similarities, and addiction to food may be an important factor in the obesity epidemic. This study aimed to determine the prevalence of food addiction among schizophrenic patients and to examine the relationship between food addiction and anthropometric measurements and dietary nutrient intake.

METHODS

Study participants included a total of 104 schizophrenic outpatients, 62 females and 42 males. Food addiction was assessed by using the Yale Food Addiction Scale, and the anthropometric measurements of participants and their three-day food consumption were recorded.

RESULTS

This study found that more than half of the schizophrenic patients (60.6%) had food addiction, and that female schizophrenic patients had a higher prevalence (62.9%) of food addiction than male patients (57.1%). More than one-third of the schizophrenic patients with food addiction (41.3%) were found to be obese and their BMI, body weight, waist circumference, and body-fat ratio were higher than those of schizophrenic patients who did not have food addiction (P > 0.05). Moreover, the schizophrenic patients with food addiction were found to take significantly more energy, carbohydrate, and fat in their diet (P < 0.05).

CONCLUSION

It was observed that the development of food addiction in schizophrenic patients increased the risk of obesity and cardiovascular diseases, which were found to be at higher levels in these patients. Educational programs should be planned for these patients to acquire health dietary habits and to increase their physical activity levels, and an additional psychosocial support should be provided for patients with food addiction.

Sex differences in addiction

Women exhibit more rapid escalation from casual drug taking to addiction, exhibit a greater withdrawal response with abstinence, and tend to exhibit greater vulnerability than men in terms of treatment outcome. In rodents, short-term estradiol intake in female rats enhances acquisition and escalation of drug taking, motivation for drugs of abuse, and relapse-like behaviors. There is also a sex difference in the dopamine response in the nucleus accumbens. Ovariectomized female rats exhibit a smaller initial dopamine increase after cocaine treatment than castrated males. Estradiol treatment of ovariectomized female rats enhances stimulated dopamine release in the dorsolateral striatum, but not in the nucleus accumbens, resulting in a sex difference in the balance between these two dopaminergic projections. In the situation where drug-taking behavior becomes habitual, dopamine release has been reported to be enhanced in the dorsolateral striatum and attenuated in the nucleus accumbens. The sex difference in the balance between these neural systems is proposed to underlie sex differences in addiction.

The prevalence of food addiction in a large sample of adolescents and its association with addictive substances

The prevalence of overweight and obesity is increasing, due to, among other factors, increased availability of highly palatable food (food high in fat, salt and/or sugar). It has been proposed that certain foods and/or eating behaviours may be addictive, to a degree comparable to substances of abuse. The Yale Food Addiction Scale (YFAS) measures 'food addiction' by translating the diagnostic criteria for substance use disorder to eating behaviour. So far, only a few studies have examined the prevalence of food addiction in children with the YFAS for children (YFAS-C). Large-scale studies, especially among adolescents, are lacking. Adolescence is of particular interest because it is a period wherein unhealthy eating behaviours or addictive tendencies are likely to develop. The current study examines the prevalence of food addiction using the YFAS-C in a large group of Dutch adolescents (N = 2653) aged 14-21 years. With Generalized Estimation Equation (GEE) analysis we tested the relationship between food addiction symptoms and smoking, cannabis use, alcohol use, and sugar intake through drinks, while controlling for gender, age, educational level and weight class. In the total sample 2.6% met the criteria for a food addiction 'diagnosis', and the average symptom count was 1.0 (SD = 1.3, range 0-7). Symptoms of food addiction were positively associated with smoking, alcohol use, cannabis use and sugar intake. We propose that future studies focus on possible genetic/(neuro)biological mechanisms involved in both food addiction and substance use and that longitudinal designs are needed to examine possible causal pathways.

Food addiction and obesity: unnecessary medicalization of hedonic overeating

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

Pathological Overeating: Emerging Evidence for a Compulsivity Construct

Compulsive eating behavior is a transdiagnostic construct that is characteristic of medical and psychiatric conditions such as forms of obesity and eating disorders. Although feeding research is moving toward a better understanding of the proposed addictive properties of food, the components and the mechanisms contributing to compulsive eating are not yet clearly defined or understood. Current understanding highlights three elements of compulsive behavior as it applies to pathological overeating: (1) habitual overeating; (2) overeating to relieve a negative emotional state; and (3) overeating despite aversive consequences. These elements emerge through mechanisms involving pathological habit formation through an aberrant learning process, the emergence of a negative emotional state, and dysfunctions in behavioral control. Dysfunctions in systems within neurocircuitries that comprise the basal ganglia, the extended amygdala, and the prefrontal cortex result in compulsive eating behaviors. Here, we present evidence to relate compulsive eating behavior and addiction and to characterize their underlying neurobiological mechanisms. A major need to improve understanding of compulsive eating through the integration of complex motivational, emotional, and cognitive constructs is warranted.