Food addiction and obesity: unnecessary medicalization of hedonic overeating

1-Deoxynojirimycin containing Morus alba leaf-based food modulates the gut microbiome and expression of genes related to obesity

BACKGROUND

Obesity is a serious disease with an alarmingly high incidence that can lead to other complications in both humans and dogs. Similar to humans, obesity can cause metabolic diseases such as diabetes in dogs. Natural products may be the preferred intervention for metabolic diseases such as obesity. The compound 1-deoxynojirimycin, present in Morus leaves and other sources has antiobesity effects. The possible antiobesity effect of 1-deoxynojirimycin containing Morus alba leaf-based food was studied in healthy companion dogs (n = 46) visiting the veterinary clinic without a history of diseases. Body weight, body condition score (BCS), blood-related parameters, and other vital parameters of the dogs were studied. Whole-transcriptome of blood and gut microbiome analysis was also carried out to investigate the possible mechanisms of action and role of changes in the gut microbiome due to treatment.

RESULTS

After 90 days of treatment, a significant antiobesity effect of the treatment food was observed through the reduction of weight, BCS, and blood-related parameters. A whole-transcriptome study revealed differentially expressed target genes important in obesity and diabetes-related pathways such as MLXIPL, CREB3L1, EGR1, ACTA2, SERPINE1, NOTCH3, and CXCL8. Gut microbiome analysis also revealed a significant difference in alpha and beta-diversity parameters in the treatment group. Similarly, the microbiota known for their health-promoting effects such as Lactobacillus ruminis, and Weissella hellenica were abundant (increased) in the treatment group. The predicted functional pathways related to obesity were also differentially abundant between groups.

CONCLUSIONS

1-Deoxynojirimycin-containing treatment food have been shown to significantly improve obesity. The identified genes, pathways, and gut microbiome-related results may be pursued in further studies to develop 1-deoxynojirimycin-based products as candidates against obesity.

Obesity surgery and neural correlates of human eating behaviour: A systematic review of functional MRI studies

Changes in eating behaviour including reductions in appetite and food intake, and healthier food cue reactivity, reward, hedonics and potentially also preference, contribute to weight loss and its health benefits after obesity surgery. Functional magnetic resonance imaging (fMRI) has been increasingly used to interrogate the neural correlates of eating behaviour in obesity, including brain reward-cognitive systems, changes after obesity surgery, and links with alterations in the gut-hormone-brain axis. Neural responses to food cues can be measured by changes in blood oxygen level dependent (BOLD) signal in brain regions involved in reward processing, including caudate, putamen, nucleus accumbens, insula, amygdala, orbitofrontal cortex, and top-down inhibitory control, including dorsolateral prefrontal cortex (dlPFC). This systematic review aimed to examine: (i) results of human fMRI studies involving obesity surgery, (ii) important methodological differences in study design across studies, and (iii) correlations and associations of fMRI findings with clinical outcomes, other eating behaviour measures and mechanistic measures. Of 741 articles identified, 23 were eligible for inclusion: 16 (69.6%) longitudinal, two (8.7%) predictive, and five (21.7%) cross-sectional studies. Seventeen studies (77.3%) included patients having Roux-en-Y gastric bypass (RYGB) surgery, six (26.1%) vertical sleeve gastrectomy (VSG), and five (21.7%) laparoscopic adjustable gastric banding (LAGB). The majority of studies (86.0%) were identified as having a very low risk of bias, though only six (27.3%) were controlled interventional studies, with none including randomisation to surgical and control interventions. The remaining studies (14.0%) had a low risk of bias driven by their control groups not having an active treatment. After RYGB surgery, food cue reactivity often decreased or was unchanged in brain reward systems, and there were inconsistent findings as to whether reductions in food cue reactivity was greater for high-energy than low-energy foods. There was minimal evidence from studies of VSG and LAGB surgeries for changes in food cue reactivity in brain reward systems, though effects of VSG surgery on food cue reactivity in the dlPFC were more consistently found. There was consistent evidence for post-operative increases in satiety gut hormones glucagon-like-peptide 1 (GLP-1) and peptide YY (PYY) mediating reduced food cue reactivity after RYGB surgery, including two interventional studies. Methodological heterogeneity across studies, including nutritional state, nature of food cues, post-operative timing, lack of control groups for order effects and weight loss or dietary/psychological advice, and often small sample sizes, limited the conclusions that could be drawn, especially for correlational analyses with clinical outcomes, other eating behaviour measures and potential mediators. This systematic review provides a detailed data resource for those performing or analysing fMRI studies of obesity surgery and makes suggestions to help improve reporting and design of such studies, as well as future directions.

Factors increasing the risk for food addiction in Ecuadorian students

Background

Food addiction (FA) is a construct that has gained interest in recent years, but its relevance in the Ecuadorian population has not yet been explored. The aims of this study were to explore the differences in the psychological profile (including FA) between university students from Ecuador and to identify the underlying structure of the relationships of the FA severity level through a mediational model.

Methods

The sample consisted of 972 university students, women and men (mean age: 20.1 years old, SD = 2.6), recruited from four Ecuadorian regions. The assessment tools included a unidimensional scale of FA, eating-related measures, emotion regulation state, impulsivity, and psychopathology state. Path analysis modeled the direct and indirect effects explaining the FA severity level.

Results

The results indicated that higher psychopathological levels were associated with FA. Similarly, no differences in FA were observed between the Ecuadorian regions. The path analysis suggested that older age, female sex, and higher difficulties in emotional regulation, impulsivity, negative mood, and anxiety trigger disordered eating; subsequently, more impaired eating behavior impacted the FA level.

Conclusion

FA is a complex clinical entity that includes multiple components related to eating disorders (EDs) and other mental health problems. The results of this study provide empirical knowledge for designing evidence-based prevention and treatment strategies.

Metabolic interactions between organs in overweight and obesity using total-body positron emission tomography

BACKGROUND AND OBJECTIVES

Overweight and obesity is a complex condition resulting from unbalanced energy homeostasis among various organs. However, systemic abnormalities in overweight and obese people are seldom explored in vivo by metabolic imaging techniques. The aim of this study was to determine metabolic abnormities throughout the body in overweight and obese adults using total-body positron emission tomography (PET) glucose uptake imaging.

METHODS

Thirty normal weight subjects [body mass index (BMI) < 25 kg/m2, 55.47 ± 13.94 years, 16 men and 14 women], and 26 overweight and obese subjects [BMI ≥ 25 kg/m2, 52.38 ± 9.52 years, 21 men and 5 women] received whole-body 18F-fluorodeoxyglucose PET imaging using the uEXPLORER. Whole-body standardized uptake value normalized by lean body mass (SUL) images were calculated. Metabolic networks were constructed based on the whole-body SUL images using covariance network approach. Both group-level and individual-level network differences between normal weight and overweight/obese subjects were evaluated. Correlation analysis was conducted between network properties and BMI for the overweight/obese subjects.

RESULTS

Compared with normal weight subjects, overweight/obese subjects exhibited altered network connectivity strength in four network nodes, namely the pancreas (p = 0.033), spleen (p = 0.021), visceral adipose tissue (VAT) (p = 1.12 × 10-5) and bone (p = 0.021). Network deviations of overweight/obese subjects from the normal weight were positively correlated with BMI (r = 0.718, p = 3.64 × 10-5). In addition, overweight/obese subjects experienced altered connections between organs, and some of the altered connections, including pancreas-right lung and VAT-bilateral lung connections were significantly correlated with BMI.

CONCLUSION

Overweight/obese individuals exhibit metabolic alterations in organ level, and altered metabolic interactions at the systemic level. The proposed approach using total-body PET imaging can reveal individual metabolic variability and metabolic deviations between organs, which would open up a new path for understanding metabolic alterations in overweight and obesity.

Are healthiness and pleasure dimensions perceived similarly by people with food addiction in Brazil? A case study using holistic sensory methodologies

The relationship between the consumption of hyper-palatable ultra-processed foods and the process of addiction gains notoriety due to its relationship with obesity. Food addiction is a complex phenomenon intrinsically related to the individual's behavioral, emotional, and subjective aspects. Therefore, using classical approaches to sensory science may be insufficient to understand better the individual's sensory experience with hyper-palatable foods. In this context, sensory and consumer science techniques with holistic approaches have been aimed at accessing more subjective consumer perceptions. This study used the Yale Food Addiction Scale (YFAS 2.0) to investigate the prevalence of food addiction and the Structured Projective Mapping (S-MP) and Sorting techniques to verify how individuals with and without food addiction perceive and understand different types of food. The prevalence of food addiction was 21.77% (n = 59 out of 271) and was associated with a higher BMI but not with sociodemographic aspects. Projective Mapping (RV = 0.937) and Sorting (RV = 0.934) indicated that perception in relation to attributes such as health and pleasure was similar for all investigated foods in individuals with or without food addiction. The presence of addictive eating behavior does not seem to be related to the way individuals perceive foods from different categories, for example, minimally or highly processed and hyper-palatable foods.

Sex Differences in the Relationship between Chronotype and Eating Behaviour: A Focus on Binge Eating and Food Addiction

BACKGROUND

Men are more likely than women to have subthreshold overeating disorders. Lifestyle plays a role as a determinant, while chronotype is an emerging factor. Chronotype explains the natural preferences of wakefulness and activity throughout the day: evening chronotypes (E-Types), those most productive in the evening, have been linked with unhealthy dietary patterns and a higher propensity to substance addiction than morning types (M-Types).

METHODS

We carried out a cross-sectional study on 750 overweight or obese adults (70% females, 48 ± 10 years, BMI 31.7 ± 5.8 kg/m2). The Binge-Eating Scale, the Yale Food Addiction Scale 2.0 (YFAS 2.0), the reduced Morningness-Eveningness Questionnaire (rMEQ), and the MEDAS questionnaire were used to assess binge eating, food addiction, chronotype, and adherence to the Mediterranean diet, respectively.

RESULTS

No differences in BES binge-eating and FA food-addiction scores occurred between chronotypes, but we found significant interactions between sex × rMEQ score. While women showed the same prevalence for binge eating and food addiction across all chronotypes, binge eating and food addiction risk increased with reducing rMEQ score in men, indicating that being male and E-Type increases the risk association of binge eating and/or food addiction prevalence.

CONCLUSIONS

chronotype is associated with binge eating and food addiction in men, emphasizing the link between chronobiology and sex differences as determinants in appetite and eating behaviour dysregulation and in overweight and obesity.

Exploring Psychological Constructs in People Receiving Treatment for Addictive Eating Behaviours: "I Hate Loving Food as Much as I Do"

Research into the complexities of addictive eating behaviours continues to develop, as a deeper understanding of this construct beyond self-report diagnostic tools emerges. In this study, we undertook structured interviews with 40 participants engaged in a personality-based management program for addictive eating, to gain insight into what situations lead people with addictive eating behaviours to overeat, and how they believe their lives would be different if they had control over their eating. A phenomenological analysis to explore compulsion and control in the context of food experiences for participants was used to construct two main themes of the addictive eating paradox and striving to transition from 'other' to 'normal'. The addictive eating paradox identified multiple contradictory experiences of a situation, e.g., 'loving food' but 'hating food'. Striving to transition from 'other' to 'normal' encompassed the idea that participants envisaged that by gaining control over their eating they could become 'normal'. This study emphasises the need to provide support and strategies to help people navigate paradoxical thoughts and presents new ideas to increase the effectiveness of interventions for individuals struggling with the complex self-beliefs held by those with addictive eating behaviours.

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.

Regulator of G-Protein Signalling 9: A New Candidate Gene for Sweet Food Liking?

Genetics plays an important role in individual differences in food liking, which influences food choices and health. Sweet food liking is a complex trait and has been associated with increased body mass index (BMI) and related comorbidities. This genome-wide association study (GWAS) aimed to investigate the genetics of sweet food liking using two adult discovery cohorts (n = 1109, n = 373) and an independent replication cohort (n = 1073). In addition, we tested the association of our strongest result on parameters related to behaviour (food adventurousness (FA) and reward dependence (RD) and health status (BMI and blood glucose). The results demonstrate a novel strong association between the Regulator of G-Protein Signalling 9 (RGS9I) gene, strongest single nucleotide polymorphism (SNP) rs58931966 (p-value 7.05 × 10^-9 in the combined sample of discovery and replication), and sweet food liking, with the minor allele (A) being associated with a decreased sweet food liking. We also found that the A allele of the rs58931966 SNP was associated with decreased FA and RD, and increased BMI and blood glucose (p-values < 0.05). Differences were highlighted in sex-specific analysis on BMI and glucose. Our results highlight a novel genetic association with food liking and are indicative of genetic variation influencing the psychological-biological drivers of food preference. If confirmed in other studies, such genetic associations could allow a greater understanding of chronic disease management from both a habitual dietary intake and reward-related perspective.

Highly processed foods can be considered addictive substances based on established scientific criteria

BACKGROUND

There is growing evidence that an addictive-eating phenotype may exist. There is significant debate regarding whether highly processed foods (HPFs; foods with refined carbohydrates and/or added fats) are addictive. The lack of scientifically grounded criteria to evaluate the addictive nature of HPFs has hindered the resolution of this debate.

ANALYSIS

The most recent scientific debate regarding a substance's addictive potential centered around tobacco. In 1988, the Surgeon General issued a report identifying tobacco products as addictive based on three primary scientific criteria: their ability to (1) cause highly controlled or compulsive use, (2) cause psychoactive (i.e. mood-altering) effects via their effect on the brain and (3) reinforce behavior. Scientific advances have now identified the ability of tobacco products to (4) trigger strong urges or craving as another important indicator of addictive potential. Here, we propose that these four criteria provide scientifically valid benchmarks that can be used to evaluate the addictiveness of HPFs. Then, we review the evidence regarding whether HPFs meet each criterion. Finally, we consider the implications of labeling HPFs as addictive.

CONCLUSION

Highly processed foods (HPFs) can meet the criteria to be labeled as addictive substances using the standards set for tobacco products. The addictive potential of HPFs may be a key factor contributing to the high public health costs associated with a food environment dominated by cheap, accessible and heavily marketed HPFs.

Signaling pathways in obesity: mechanisms and therapeutic interventions

Obesity is a complex, chronic disease and global public health challenge. Characterized by excessive fat accumulation in the body, obesity sharply increases the risk of several diseases, such as type 2 diabetes, cardiovascular disease, and nonalcoholic fatty liver disease, and is linked to lower life expectancy. Although lifestyle intervention (diet and exercise) has remarkable effects on weight management, achieving long-term success at weight loss is extremely challenging, and the prevalence of obesity continues to rise worldwide. Over the past decades, the pathophysiology of obesity has been extensively investigated, and an increasing number of signal transduction pathways have been implicated in obesity, making it possible to fight obesity in a more effective and precise way. In this review, we summarize recent advances in the pathogenesis of obesity from both experimental and clinical studies, focusing on signaling pathways and their roles in the regulation of food intake, glucose homeostasis, adipogenesis, thermogenesis, and chronic inflammation. We also discuss the current anti-obesity drugs, as well as weight loss compounds in clinical trials, that target these signals. The evolving knowledge of signaling transduction may shed light on the future direction of obesity research, as we move into a new era of precision medicine.

Development of the Hedonic Overeating–Questionnaire (HEDO–Q)

Addictive-like eating is prevalent, but a clear conceptualization and operationalization outside of an addiction framework is lacking. By adopting a biopsychological framework of food reward, this study sought to develop and evaluate a brief self-report questionnaire for the trait assessment of hedonic overeating and dyscontrol. Items in the Hedonic Overeating–Questionnaire (HEDO–Q) were constructed following a rational approach and psychometrically evaluated in a large random sample from the German population (N = 2531). A confirmatory factor analysis supported the unidimensional nature of the six-item HEDO–Q with the three postulated components of wanting, liking, and dyscontrol. Psychometric properties were favorable with good corrected item-total correlations, acceptable item difficulty and homogeneity, and high internal consistency. Population norms were provided. The HEDO–Q revealed strict measurement invariance for sex and partial invariance for age and weight status. Discriminant validity was demonstrated in distinguishing participants with versus without eating disturbances or obesity. Associations with the established measures of eating disorder and general psychopathology supported the convergent and divergent validity of the HEDO–Q. This first evaluation indicates good psychometric properties of the HEDO–Q in the general population. Future validation work is warranted on the HEDO–Q’s stability, sensitivity to change, and predictive and construct validity.

Motivation to consume palatable foods as a predictor of body image dissatisfaction: Using the Power of Food Scale in a Brazilian sample

The Power of Food Scale (PFS) is a questionnaire for self-assessing the motivation to consume palatable foods, especially in environments where food is abundant and constantly available. This study aimed to a) assess the factorial structure of the PFS in a Brazilian sample and b) examine the relationship between the power of food and body image dissatisfaction and BMI. The PFS and Body Shape Questionnaire (BSQ) were applied to a sample of 300 adults. Data were analysed using confirmatory factor analysis. Composite reliability (CR) was used to verify factor reliability. A partial least squares structural equation model was used to verify the effect of the PFS score on body image dissatisfaction. The PFS had an adequate factorial structure in this Brazilian sample, showing three well-defined factors: food available (CR = 0.91), food tasted (CR = 0.84), and food present (CR = 0.87). The BSQ showed one reliable factor (CR = 0.97). The power of the food aggregate factor significantly predicted body mass index (β = 0.16; p = .01) and body image dissatisfaction (β = 0.46; p < .001). The effect size was small for body mass index (f² = 0.02) and medium for body image dissatisfaction (f² = 0.26). The food present factor also had a slightly higher average among the three PFS factors. Women had higher PFS scores than men. Understanding the role that this motivation plays in physical and psychological outcomes such as body dissatisfaction can contribute to developing treatment strategies and support health professionals' performance in clinical settings.

Integrative Hedonic and Homeostatic Food Intake Regulation by the Central Nervous System: Insights from Neuroimaging

Food intake regulation in humans is a complex process controlled by the dynamic interaction of homeostatic and hedonic systems. Homeostatic regulation is controlled by appetitive signals from the gut, adipose tissue, and the vagus nerve, while conscious and unconscious reward processes orchestrate hedonic regulation. On the one hand, sight, smell, taste, and texture perception deliver potent food-related feedback to the central nervous system (CNS) and influence brain areas related to food reward. On the other hand, macronutrient composition stimulates the release of appetite signals from the gut, which are translated in the CNS into unconscious reward processes. This multi-level regulation process of food intake shapes and regulates human ingestive behavior. Identifying the interface between hormones, neurotransmitters, and brain areas is critical to advance our understanding of conditions like obesity and develop better therapeutical interventions. Neuroimaging studies allow us to take a glance into the central nervous system (CNS) while these processes take place. This review focuses on the available neuroimaging evidence to describe this interaction between the homeostatic and hedonic components in human food intake regulation.

The Effect of Artificial Sweeteners Use on Sweet Taste Perception and Weight Loss Efficacy: A Review

Excessive consumption of sugar-rich foods is currently one of the most important factors that has led to the development of the global pandemic of obesity. On the other hand, there is evidence that obesity contributes to reduced sensitivity to sweet taste and hormonal changes affecting appetite, leading to an increased craving for sweets. A high intake of sugars increases the caloric value of the diet and, consequently, leads to weight gain. Moreover, attention is drawn to the concept of the addictive properties of sugar and sugary foods. A potential method to reduce the energy value of diet while maintaining the sweet taste is using non-nutritive sweeteners (NNS). NNS are commonly used as table sugar substitutes. This wide group of chemical compounds features high sweetness almost without calories due to its high sweetening strength. NNS include aspartame, acesulfame-K, sucralose, saccharin, cyclamate, neohesperidin dihydrochalcone (neohesperidin DC), neotame, taumatin, and advantame. The available evidence suggests that replacing sugar with NNS may support weight control. However, the effect of NNS on the regulation of appetite and sweet taste perception is not clear. Therefore, the review aimed to summarize the current knowledge about the use of NNS as a potential strategy for weight loss and their impact on sweet taste perception. Most studies have demonstrated that consumption of NNS-sweetened foods does not increase sweetness preference orenergy intake. Nonetheless, further research is required to determine the long-term effects of NNS on weight management.

Taste of Fat and Obesity: Different Hypotheses and Our Point of View

Obesity results from a temporary or prolonged positive energy balance due to an alteration in the homeostatic feedback of energy balance. Food, with its discriminative and hedonic qualities, is a key element of reward-based energy intake. An alteration in the brain reward system for highly palatable energy-rich foods, comprised of fat and carbohydrates, could be one of the main factors involved in the development of obesity by increasing the attractiveness and consumption of fat-rich foods. This would induce, in turn, a decrease in the taste of fat. A better understanding of the altered reward system in obesity may open the door to a new era for the diagnosis, management and treatment of this disease.

Behavioral Interventions to Attenuate Driven Overeating and Weight Regain After Bariatric Surgery

Weight regain after bariatric surgery is associated with problematic eating behaviors that have either recurred after a period of improvement or are new-onset behaviors. Problematic eating behaviors after bariatric surgery have been conceptualized in different ways in the literature, such as having a food addiction and experiencing a loss of control of eating. The intersection of these constructs appears to be driven overeating defined as patients' experiences of reduced control of their eating which results in overeating behavior. The purpose of this review is to define patient experiences of driven overeating through the behavioral expression of emotion-based eating, reward-based eating, and executive functioning deficits-namely impulsivity-which is associated with weight regain after having bariatric surgery. Delineating concepts in this way and determining treatment strategies accordingly may reduce distress related to the inevitable return of increased hunger, cravings, portion sizes, and tolerance for highly palatable foods after surgery. Along with standard behavioral weight maintenance strategies, topics including acceptance, motivation, emotion-based eating, reward-based/impulsive eating, physical activity, and self-compassion are discussed. These concepts have been adapted for patients experiencing weight regain after having bariatric surgery and may be particularly helpful in attenuating driven overeating and weight regain.

Cognitive function in binge eating disorder and food addiction: A systematic review and three-level meta-analysis

BACKGROUND

An extensive body of recent research has focused on the contribution of cognitive functioning to eating behaviors. In binge eating disorder (BED) and food addiction (FA), the extent of cognitive impairment is still unclear. This study aimed to characterize, among those with BED and FA, neurocognitive functions using performances based on neuropsychological tasks in the context of neutral stimuli in adults.

METHOD

MEDLINE, Embase, PsycINFO, Cochrane Database of Systematic Reviews, CINAHL and gray literature (ProQuest and OpenGrey) were used to identify studies that reported neurocognitive assessments in BED or FA up to December 2019. A three-level meta-analysis was conducted.

RESULTS

A significant overall effect was found for global cognitive impairments, suggesting that individuals with BED or FA have poorer performances when completing cognitive tasks. Analyses for specific cognitive domains revealed that individuals with BED showed poorer performances at tasks assessing cognitive flexibility, inhibitory control, attention and planning. Analyses regarding FA were inconclusive due to a lack of studies. Thus, the results were described qualitatively.

CONCLUSION

Our meta-analysis highlighted the cognitive weaknesses that seem to come with BED and the necessity to integrate them in the assessment and treatment of this condition. It also stressed the lack of quality studies surrounding the cognitive features of FA.

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.

Examining impairment and distress from food addiction across demographic and weight groups

Rates of food addiction (FA) vary across weight and demographic groups. Factors influencing discrepant prevalence rates are largely unknown. Rates of clinically significant distress or impairment also vary across demographic groups, yet prior studies have overlooked the diagnostic significance of distress/impairment in heterogenous groups. We tested if weight and demographic groups differed in their likelihood of endorsing distress/impairment from FA. Participants (N = 1832) recruited from Amazon Mechanical Turk completed the modified Yale Food Addiction Scale 2.0 (mYFAS). The mYFAS includes 11 dichotomous symptom indicators and one dichotomous distress/impairment indicator. Differences in distress/impairment were tested across weight, sex, racial/ethnic, and educational groups using logistic regression. FA severity was controlled for using FA symptom count. There were no differences among racial/ethnic and educational groups (p > 0.05). Compared to men, women were more likely to report distress/impairment (aOR = 1.96, 95% CI = 1.28-3.03). People with obesity were more likely to report distress/impairment compared to people with overweight (aOR = 2.20, 95% CI = 1.39-3.49) or normal weight (aOR = 1.99, 95% CI = 1.26-3.13). Individual characteristics (i.e., sex, weight) may influence reporting of distress/impairment from FA. Further inquiry may be appropriate for men and people with normal weight or overweight presenting with FA symptoms who otherwise deny distress/impairment.

The Relationship of Food Addiction With Other Eating Pathologies and Impulsivity: A Case-Control Study

The concept of food addiction (FA) has become central in recent years in understanding the psychological etiology of obesity. In this matched case-control study from Turkey, it was aimed to examine the prevalence of FA and related risk factors in four consecutive body mass index (BMI) categories. The case group consisted of pre-operative bariatric surgery patients with BMI over 35.0 kg/m2 (n = 40) and the control group was composed of age- and gender- matching individuals from the other categories, namely obese (n = 35), overweight (n = 40), and normal weight (n = 40). The Yale Food Addiction Scale (YFAS) and a standardized clinical interview using the DSM-5 substance use disorders criteria adopted for FA, the Eating Disorder Examination Questionnaire (EDEQ) and the Barratt Impulsivity Scale (BIS-11) were used as assessment instruments. It was found that FA was significantly associated with more serious eating pathologies, more frequent weight-cycling and earlier onset of dieting, higher impulsivity, and higher BMI. Motor and total impulsivity scores showed a positive albeit week correlation with the severity of FA but no significant correlation with BMI, indicating a relationship between impulsivity and weight gain in some but not all individuals. The severity of FA predicted the increase in BMI. Our findings suggest that FA is associated with weight gain in a group of individuals, plausibly through impulsive overeating. Emphasis on FA and its clinical implications such as addiction-based treatments may improve outcomes in obesity and facilitate health promotion.

Sleep dysregulation in binge eating disorder and "food addiction": the orexin (hypocretin) system as a potential neurobiological link

It has been proposed that binge eating reflects a pathological compulsion driven by the "addictive" properties of foods. Proponents of this argument highlight the large degree of phenomenological and diagnostic overlap between binge eating disorder (BED) and substance use disorders (SUDs), including loss of control over how much is consumed and repeated unsuccessful attempts to abstain from consumption, as well as commonalities in brain structures involved in food and drug craving. To date, very little attention has been given to an additional behavioral symptom that BED shares with SUDs-sleep dysregulation-and the extent to which this may contribute to the pathophysiology of BED. Here, we review studies examining sleep outcomes in patients with BED, which collectively point to a heightened incidence of sleep abnormalities in BED. We identify the orexin (hypocretin) system as a potential neurobiological link between compulsive eating and sleep dysregulation in BED, and provide a comprehensive update on the evidence linking this system to these processes. Finally, drawing on evidence from the SUD literature indicating that the orexin system exhibits significant plasticity in response to drugs of abuse, we hypothesize that chronic palatable food consumption likewise increases orexin system activity, resulting in dysregulated sleep/wake patterns. Poor sleep, in turn, is predicted to exacerbate binge eating, contributing to a cycle of uncontrolled food consumption. By extension, we suggest that pharmacotherapies normalizing orexin signaling, which are currently being trialed for the treatment of SUDs, might also have utility in the clinical management of BED.

Peter JV. Sugars and Sweet Taste: Addictive or Rewarding?

The notion of food "addiction" often focuses on the overconsumption of sweet tasting foods or so-called sugar "addiction". In the extreme, some have suggested that sugar and sweet tastes elicit neural and behavioral responses analogous to those observed with drugs of abuse. These concepts are complicated by the decades long uncertainty surrounding the validity and reproducibility of functional magnetic resonance imaging (fMRI) methodologies used to characterize neurobiological pathways related to sugar and sweet taste stimuli. There are also questions of whether sweet taste or post-ingestion metabolic consequences of sugar intake would lead to addiction or excessive caloric intake. Here, we present a focused narrative review of literature related to the reward value of sweet taste which suggests that reward value can be confounded with the construct of "addictive potential". Our review seeks to clarify some key distinctions between these constructs and questions the applicability of the addiction construct to human over-eating behaviors. To adequately frame this broad discussion requires the flexibility offered by the narrative review paradigm. We present selected literature on: techniques used to link sugar and sweet tastes to addiction neurobiology and behaviors; sugar and sweet taste "addiction"; the relationship of low calorie sweetener (LCS) intake to addictive behaviors and total calorie intake. Finally, we examined the reward value of sweet tastes and contrasted that with the literature describing addiction. The lack of reproducibility of fMRI data remains problematic for attributing a common neurobiological pathway activation of drugs and foods as conclusive evidence for sugar or sweet taste "addiction". Moreover, the complicated hedonics of sweet taste and reward value are suggested by validated population-level data which demonstrate that the consumption of sweet taste in the absence of calories does not increase total caloric intake. We believe the neurobiologies of reward value and addiction to be distinct and disagree with application of the addiction model to sweet food overconsumption. Most hypotheses of sugar "addiction" attribute the hedonics of sweet foods as the equivalent of "addiction". Further, when addictive behaviors and biology are critically examined in totality, they contrast dramatically from those associated with the desire for sweet taste. Finally, the evidence is strong that responses to the palatability of sweets rather than their metabolic consequences are the salient features for reward value. Thus, given the complexity of the controls of food intake in humans, we question the usefulness of the "addiction" model in dissecting the causes and effects of sweet food over-consumption.

Translation of the Chinese version of the modified Yale Food Addiction Scale 2.0 and its validation among college students

BACKGROUND

Obesity prevalence has substantially increased in China over the past decade. In China, over 1 in 7 individuals meet the criteria for overall obesity, and 1 in 3 meet the criteria for abdominal obesity, obesity has become a significant problem. Studies have shown that food addiction and obesity are inextricably linked. The modified Yale Food Addiction Scale 2.0 (mYFAS 2.0) is a brief measurement for assessing food addiction. This study aimed to explore the structure of the Chinese version of the mYFAS 2.0 and assess the occurrence of food addiction in a sample of college students in Northeast China.

METHODS

A cross-sectional design was conducted in a sample of 1099 undergraduate students in Northeast China. Participants completed the sociodemographic questionnaire, the Chinese version of the mYFAS 2.0, the Barratt Impulsiveness Scale (BIS-8), and the Self-Esteem Scale (SES) to test the hypothesis. Exploratory factor analysis and confirmatory factor analysis were performed to examine the underlying factor structure of the mYFAS 2.0. Two weeks later, 62 students who participated in the first test were recruited to evaluate the test-retest reliability.

RESULTS

The Chinese version of the mYFAS 2.0 demonstrated adequate internal consistency, good test-retest reliability and satisfactory construct validity. The results of the confirmatory factor analysis found that the Chinese version of the mYFAS 2.0 demonstrated a good fit to the two-factor solution identified by the exploratory factor analysis and showed superior fit indices compared to the one-factor model. The prevalence of food addiction in our sample was found to be in line with rates observed in other Asian and Western samples. The mYFAS 2.0 symptom count scores were correlated with BMI, the idea of dieting to lose weight, the desire to overeat, low self-esteem, and impulsivity.

CONCLUSION

The results indicate that the Chinese version of the mYFAS 2.0 has good reliability and validity, and that it can be considered a tool to evaluate the addictive eating behaviours of undergraduate students.

A narrative review of reward sensitivity, rash impulsivity, and food addiction in adolescents

Adolescence represents a neurodevelopmental period characterised by heightened reward drive and weaker inhibitory control that may increase vulnerability to compulsive overconsumption of highly-palatable foods and food addiction. This narrative review aimed to summarise research investigating the presence of food addiction in adolescents and establish the role that impulsivity traits (i.e., reward sensitivity and rash impulsivity), previously linked to substance and behavioural addictions, play in contributing to food addiction in this cohort. It was found that the prevalence of food addiction was typically higher in studies that recruited adolescents who were overweight/obese or from clinical populations. Overall, impulsivity was found to be more consistently associated with food addiction, while the relationships between measures of reward sensitivity and food addiction were mixed. Findings of this review suggest trait impulsivity may contribute to food addiction in adolescents, however, further longitudinal and prospective research is recommended to confirm these findings and to investigate the potential interactive effects of reward sensitivity and rash impulsivity.

Decoding the Role of Gut-Microbiome in the Food Addiction Paradigm

Eating behaviour is characterised by a solid balance between homeostatic and hedonic regulatory mechanisms at the central level and highly influenced by peripheral signals. Among these signals, those generated by the gut microbiota have achieved relevance in recent years. Despite this complex regulation, under certain circumstances eating behaviour can be deregulated becoming addictive. Although there is still an ongoing debate about the food addiction concept, studies agree that patients with eating addictive behaviour present similar symptoms to those experienced by drug addicts, by affecting central areas involved in the control of motivated behaviour. In this context, this review tries to summarise the main data regarding the role of the gut microbiome in eating behaviour and how a gut dysbiosis can be responsible for a maladaptive behaviour such as “food addiction”.

The food craving inventory in an Iranian population: post-hoc validation and individual differences

PURPOSE

The present study was performed to develop the Persian version of food craving inventory (FCI) (FCI-P) and to assess food craving in Iranian adult population. In addition, individual differences, including sex and body mass index (BMI) in food craving were assessed.

METHODS

Eight hundred and twenty subjects who participated in the same study Hill (Proc Nutr Soc 66: 277-285, 2007) were studied (540 women and 280 men). The FCI-P, International Physical Activity Questionnaire (IPAQ), Three-Factor Eating Questionnaire (TFEQ), and a questionnaire pertaining to demographic characteristics were completed for all participants.

RESULTS

Good content, construct, and convergent validity was observed for the FCI-P. A good reliability was found for both aggregate scores of the FCI-P and scores of its five factors. Exploratory factor analysis showed a five-factor model including "sweets," "high-fat foods," "fast food fats," "carbohydrates/starches" and "high-fat meats". These five factors accounted for 47.31% of the total variance. The scores of "uncontrolled eating" and "emotional eating" of the TFEQ were significantly correlated with the scores of the FCI-P factors and its total score. A significant correlation was found between BMI and the FCI-P score (r = 0.199). Significant differences were observed in the mean age and physical activity score among normal weight, overweight, and obese participants. Normal weight and overweight groups were more active than obese group. Obese participants had higher FCI-P score (P < 0.001) than the normal and overweight groups. FCI-P score was significantly higher in women than men.

CONCLUSIONS

FCI-P can be used as a valid and reliable measure to assess food craving in Iranian populations. Obese individuals experienced food craving more than normal weight subjects. Similarly, women may experience food craving more than men.

LEVEL OF EVIDENCE

Level V, cross sectional study.

Prevalence and correlates of food addiction: Systematic review of studies with the YFAS 2.0

BACKGROUND

Research on food addiction (FA) has been growing and increasing interest has been seen in comprehending its mechanisms and clinical and psychological correlates of this phenomena. This field of study is specially apply to understand obesity and eating behavior issues related to eating disorders (ED).

OBJECTIVES

We performed a literature review that describe recent research using the updated version of the Yale Food Addiction Scale (YFAS 2.0) or modified-YFAS (mYFAS 2.0), from the date of its publication.

METHODS

Search were performed in Web of Science, Pubmed and PsycNET databases for studies that used the YFAS 2.0 and mYFAS 2.0.

RESULTS

The studies (n = 53) investigated adaptation and validation of the scale in different cultures (n = 13), prevalence on nonclinical populations and representative samples (n = 5), food addiction in obesity samples (n = 11), in samples with ED and disordered eating (n = 10) and studies that investigated FA in association with other clinical and psychological variables (n = 14).

DISCUSSION

Studies with the YFAS 2.0 reveal higher prevalence of FA in different samples, and a great association between FA and BED, BN and obesity. Implications for diagnostic of this phenomena and the overlap between FA and other disorders are discussed.

CONCLUSIONS

The field of FA remains an open subject and effort must be implied to understand the subjective experience of addiction related to eating and food.

Body image disturbance partially explains eating-related psychosocial impairment in food addiction

BACKGROUND

This study aimed to explore the association of food addiction (FA) with eating-related psychosocial impairment and examine the extent to which this association was explained directly by FA symptoms themselves, versus through body image disturbance.

MATERIALS AND METHODS

Participants (356 university students and 544 crowdsourced adults) completed self-report measures of FA (Yale Food Addiction Scale; YFAS 2.0), psychosocial impairment (Clinical Impairment Assessment; CIA 3.0), and body image disturbance (Eating Disorders Examination Questionnaire; EDE-Q 6.0), and reported their body mass index (BMI) and gender.

RESULTS

Endorsement of distress and/or impairment on the YFAS corresponded to ratings on the CIA. Structural equation models indicated the relationship between FA and eating-related psychosocial impairment was partially mediated by body image disturbance. The indirect effect of body image disturbance explained more variance in eating-related psychosocial impairment than did YFAS scores themselves. Neither BMI nor gender significantly moderated any direct or indirect pathways from food addiction to psychosocial impairment.

CONCLUSIONS

Food addiction is associated with clinical impairment in men and women across the weight spectrum. A large portion of psychosocial impairment associated with food addiction may be explained by body image disturbance. Due to its role in explaining psychosocial impairment, body image disturbance warrants increased attention in FA research.

Dietary Management of Obesity: A Review of the Evidence

Obesity is a multi-factorial disease and its prevention and management require knowledge of the complex interactions underlying it and adopting a whole system approach that addresses obesogenic environments within country specific contexts. The pathophysiology behind obesity involves a myriad of genetic, epigenetic, physiological, and macroenvironmental factors that drive food intake and appetite and increase the obesity risk for susceptible individuals. Metabolically, food intake and appetite are regulated via intricate processes and feedback systems between the brain, gastrointestinal system, adipose and endocrine tissues that aim to maintain body weight and energy homeostasis but are also responsive to environmental cues that may trigger overconsumption of food beyond homeostatic needs. Under restricted caloric intake conditions such as dieting, these processes elicit compensatory metabolic mechanisms that promote energy intake and weight regain, posing great challenges to diet adherence and weight loss attempts. To mitigate these responses and enhance diet adherence and weight loss, different dietary strategies have been suggested in the literature based on their differential effects on satiety and metabolism. In this review article, we offer an overview of the literature on obesity and its underlying pathological mechanisms, and we present an evidence based comparative analysis of the effects of different popular dietary strategies on weight loss, metabolic responses and diet adherence in obesity.

Treatment of the sensory and motor components of urges to eat (eating addiction?): a mobile-health pilot study for obesity in young people

PURPOSE

Compelling evidence indicates that an addictive process might contribute to overeating/obesity. We hypothesize that this process consists of two components: (a) a sensory addiction to the taste, texture, and temperature of food, and (b) a motor addiction to the actions of eating (e.g., biting, chewing, crunching, sucking, swallowing). Previously, we reported a mobile health application (mHealth app) obesity intervention addressing the sensory addiction component, based on staged food withdrawal. We propose that the motor addiction component can be treated using cognitive behavioral therapy (CBT)-based strategies for body-focused repetitive behaviors (BRFB), e.g., nail biting, skin picking, and hair pulling.

METHODS

The present study tested the effectiveness of CBT-based, BFRB therapies added to the staged withdrawal app. Thirty-five participants, ages 8-20, 51.4% females, mean zBMI 2.17, participated in a 4-month study using the app, followed by a 5-month extension without the app. Using staged withdrawal, participants withdrew from specific, self-identified, "problem" foods until cravings resolved; then from non-specific snacking; and lastly from excessive mealtime amounts. BFRB therapies utilized concurrently included: distractions, competing behaviors, triggers avoidance, relaxation methods, aversion techniques, and distress tolerance.

RESULTS

Latent growth curve analysis determined that mean body weight and zBMI decreased significantly more than in a previous study that used only staged withdrawal (p < 0.01). In the 5-month follow-up, participants maintained overall weight loss.

CONCLUSIONS

This study provides further preliminary evidence for the acceptability of an addiction model treatment of obesity in youth, and that the addition of CBT-based, BFRB therapies increased the effectiveness of staged food withdrawal.

LEVEL OF EVIDENCE

Level IV, Evidence obtained from multiple time series analysis with the intervention.

Western Diet: Implications for Brain Function and Behavior

The Western diet (WD) pattern characterized by high daily intake of saturated fats and refined carbohydrates often leads to obesity and overweight, and it has been linked to cognitive impairment and emotional disorders in both animal models and humans. This dietary pattern alters the composition of gut microbiota, influencing brain function by different mechanisms involving the gut-brain axis. In addition, long-term exposure to highly palatable foods typical of WD could induce addictive-like eating behaviors and hypothalamic-pituitary-adrenal (HPA) axis dysregulation associated with chronic stress, anxiety, and depression. In turn, chronic stress modulates eating behavior, and it could have detrimental effects on different brain regions such as the hippocampus, hypothalamus, amygdala, and several cortical regions. Moreover, obesity and overweight induce neuroinflammation, causing neuronal dysfunction. In this review, we summarize the current scientific evidence about the mechanisms and factors relating WD consumption with altered brain function and behavior. Possible therapeutic interventions and limitations are also discussed, aiming to tackle and prevent this current pandemic.

The Clinical Utility of Food Addiction: Characteristics and Psychosocial Impairments in a Treatment-Seeking Sample

Little is known about the characteristics of individuals seeking treatment for food addiction (FA), and the clinical utility of FA has yet to be established. To address these gaps, we examined (i) the demographic, eating pathology, and psychiatric conditions associated with FA and (ii) whether FA is associated with psychosocial impairments when accounting for eating-related and other psychopathology. Forty-six patients seeking treatment for FA completed self-report questionnaires and semi-structured clinical interviews. The majority of the sample were women and self-identified as White, with a mean age of 43 years. Most participants (83.3%) presented with a comorbid psychiatric condition, most commonly anxiety and mood disorders, with a mean of 2.31 comorbid conditions. FA was associated with binge eating severity and anxiety symptoms, as well as psychological, physical, and social impairment. In regression analyses controlling for binge eating severity, food cravings, depression, and anxiety, FA remained a significant predictor only of social impairment. Taken together, the results suggest that individuals seeking treatment for FA are likely to present with significant comorbid conditions, in particular anxiety disorders. The results of the present research provide evidence for the clinical utility of FA, particularly in explaining social impairment.

Development and Validation of the Recognizing Addictive Disorders Scale: A Transdiagnostic Measure of Substance-Related and Other Addictive Disorders

OBJECTIVE

Substance use disorders and behavioral addictions commonly co-occur. However, few available self-report measures reliably and validly assess the full range of addictive conditions. The development and initial validation of a new measure-Recognizing Addictive Disorders (RADs) scale addresses a significant gap in the literature. Method: After items were generated and evaluated in Study 1, Study 2 (N = 300), applied exploratory factor analysis to the item pool using an online-based community sample. In Study 3 (N = 427), the factor structure was validated using an independent online-based community sample and confirmatory factor analysis. Results: The scale demonstrated good internal consistency (a = .92) and construct validity, including replication of the factor structure (χ2 (553) = 760.83, p < .001, CFI = .997, TLI = .997, RMSEA = .030) and correlation with a related transdiagnostic measure of addiction (r = .72). Discussion: Overall, results support the preliminary validity of a brief transdiagnostic measure of addiction that considers a diverse range of behaviors. For patients presenting to substance abuse treatment, this tool may be useful in identifying symptoms of other types of non-substance problems, which could ultimately aid in treatment planning.

Cultural Moderation of Unconscious Hedonic Responses to Food

Previous psychological studies have shown that images of food elicit hedonic responses, either consciously or unconsciously, and that participants' cultural experiences moderate conscious hedonic ratings of food. However, whether cultural factors moderate unconscious hedonic responses to food remains unknown. We investigated this issue in Polish and Japanese participants using the subliminal affective priming paradigm. Images of international fast food and domestic Japanese food were presented subliminally as prime stimuli. Participants rated their preferences for the subsequently presented target ideographs. Participants also rated their preferences for supraliminally presented food images. In the subliminal rating task, Polish participants showed higher preference ratings for fast food primes than for Japanese food primes, whereas Japanese participants showed comparable preference ratings across these two conditions. In the supraliminal rating task, both Polish and Japanese participants reported comparable preferences for fast and Japanese food stimuli. These results suggest that cultural experiences moderate unconscious hedonic responses to food, which may not be detected based on explicit ratings.

An ecological momentary episodic future thinking intervention on mother's weekly food purchases

BACKGROUND

Imagining one's own future (episodic future thinking, EFT) has helped mothers with overweight purchase healthier groceries during an online shopping task in the laboratory. The present study explored whether delivering an EFT intervention to participants' devices via an ecological momentary intervention (EMI) tool would help mothers purchase healthier food at brick-and-mortar stores.

METHOD

Participants (N = 43, mothers 31-52 years of age, BMI ≥ 24.9 kg/m2) were randomized to EFT or standardized episodic thinking (SET). EFT cues include a positive and vivid description of future events while SET cues focus on the recent experience of playing games in the laboratory. Cues were uploaded to participant profiles on an EMI site. Participants were trained on how to read and listen to cues as well as how to detail purchases. Participants received text reminders to listen to cues before shopping and returned with receipts the following day. Receipt data was analyzed to derive dependent variables, calories, and nutrients purchased per person. Correlations were used to analyze associations between study variables of interest, and ANOVAs were conducted to compare dietary variables by group.

RESULTS

Participants in the EFT group purchased fewer calories, fewer grams of fat, fewer grams of saturated fat, and fewer miligrams of sodium than participants in the SET control group.

CONCLUSION

Delivering EFT cues to participant devices may be a promising way to improve the calorie and nutrient content of food purchases. Future research should include a longer follow-up and analyze calorie changes over time. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Is weight status associated with peripheral levels of oxytocin? A pilot study in healthy women

The neuropeptide oxytocin is best known for its role during parturition and the milk-let down reflex. Recent evidence identifies a role for oxytocin in eating behaviour. After oxytocin administration, caloric intake is reduced with stronger inhibitory effects in individuals with obesity. Whether the experience of visual food cues affects secretion or circulating levels of oxytocin is unknown. This pilot study had three aims: 1) to measure fasting appetite hormones with a focus on plasma oxytocin concentrations; 2) determine whether healthy vs. hyperpalatable visual food cues differentially altered plasma oxytocin; and 3) assess whether appetite hormone responses to healthy vs. hyperpalatable food images depended on weight or food addiction status. Eighteen healthy women of varying weight status, with/without self-reported food addiction were recruited. Study participants completed a set of standardised questionnaires, including Yale Food Addiction Scale, and attended a one-off experimental session. Blood was collected before and after viewing two sets of food images (healthy and hyperpalatable foods). Participants were randomly allocated in a crossover design to view either healthy images or hyperpalatable foods first. A positive correlation between BMI and plasma oxytocin was found (r² = 0.32, p = 0.021) at baseline. Oxytocin levels were higher, and cholecystokinin levels lower, in food addicted (n = 6) vs. non-food addicted females (p = 0.015 and p<0.001, respectively). There were no significant changes (p>0.05) in plasma oxytocin levels in response to either healthy or hyperpalatable food images. Given that endogenous oxytocin administration tends to suppress eating behaviour; these data indicate that oxytocin receptor desensitization or oxytocin resistance may be important factors in the pathogenesis of obesity and food addiction. However, further studies in larger samples are needed to determine if peripheral oxytocin is responsive to visual food cues.

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).

Alisol A attenuates high-fat-diet-induced obesity and metabolic disorders via the AMPK/ACC/SREBP-1c pathway

Obesity and its associated metabolic disorders such as diabetes, hepatic steatosis and chronic heart diseases are affecting billions of individuals. However there is no satisfactory drug to treat such diseases. In this study, we found that alisol A, a major active triterpene isolated from the Chinese traditional medicine Rhizoma Alismatis, could significantly attenuate high‐fat‐diet‐induced obesity. Our biochemical detection demonstrated that alisol A remarkably decreased lipid levels, alleviated glucose metabolism disorders and insulin resistance in high‐fat‐diet‐induced obese mice. We also found that alisol A reduced hepatic steatosis and improved liver function in the obese mice model.In addition, protein expression investigation revealed that alisol A had an active effect on AMPK/ACC/SREBP‐1c pathway. As suggested by the molecular docking study, such bioactivity of alisol A may result from its selective binding to the catalytic region of AMPK.Therefore, we believe that Alisol A could serve as a promising agent for treatment of obesity and its related metabolic diseases.

Amygdala activation during unconscious visual processing of food

Hedonic or emotional responses to food have important positive and negative effects on human life. Behavioral studies have shown that hedonic responses to food images are elicited rapidly, even in the absence of conscious awareness of food. Although a number of previous neuroimaging studies investigated neural activity during conscious processing of food images, the neural mechanisms underlying unconscious food processing remain unknown. To investigate this issue, we measured neural activity using functional magnetic resonance imaging while participants viewed food and mosaic images presented subliminally and supraliminally. Conjunction analyses revealed that the bilateral amygdala was more strongly activated in response to food images than to mosaic images under both subliminal and supraliminal conditions. Interaction analyses revealed that the broad bilateral posterior regions, peaking at the posterior fusiform gyrus, were particularly active when participants viewed food versus mosaic images under the supraliminal compared with the subliminal condition. Dynamic causal modeling analyses supported the model in which the subcortical visual pathway from the pulvinar to the amygdala was modulated by food under the subliminal condition; in contrast, the model in which both subcortical and cortical (connecting the primary visual cortex, fusiform gyrus, and the amygdala) visual pathways were modulated by food received the most support under the supraliminal condition. These results suggest the possibility that unconscious hedonic responses to food may exert an effect through amygdala activation via the subcortical visual pathway.

Attentional bias and response inhibition in severe obesity with food disinhibition: a study of P300 and N200 event-related potential

BACKGROUND/OBJECTIVE

In obesity there is growing evidence for common mechanism between food intake regulation and substance use disorders, especially more attentional bias and less cognitive control. In the present study we investigated whether severely obese subjects with or without disordered eating exhibit electroencephalographic (EEG) event-related potential (ERP) modifications as observed in substance abusers.

SUBJECTS/METHODS

A total of 90 women were included; 30 in the normal-weight (NW) group (18.5 < BMI < 24.5 kg/m²; no food disinhibition or restriction on the Three-Factor Eating Questionnaire) and 60 participants with BMI ≥ 35 kg/m² were separated into two groups (n = 30): without food disinhibition (disinhibition score ≤8; ObFD- group) and with food disinhibition (score >8; ObFD+). Clinical and metabolic parameters as well as compartmental aspects (Eating Disorders Inventory-2, EDI-2) were assessed. Participants underwent an ERP recording with an auditory oddball paradigm.

RESULTS

The mean ± SD P300 amplitudes in Pz were significantly (p < 0.05) lower in ObFD- (12.4 ± 4.6) and ObFD+ (12.5 ± 4.4) groups than in the NW group (15.8 ± 5.9). The mean ± SD N200 amplitude in Cz was significantly lower in the ObFD- group (-2.0 ± 5.4) than in the NW group (-5.2 ± 4.2 vs; p = 0.035). N200 Cz amplitude was correlated with EDI-2 Binge eating risk score (ρ = 0.331; p = 0.01), EDI-2 Body Dissatisfaction score (ρ = 0.351; p = 0.007), and Drive for Thinness score (ρ = 0.26; p = 0.05).

CONCLUSIONS

The present study provides evidence for reduction of P300 and N200 amplitude in obese women and that N200 amplitude may be related to more disordered eating and eating disorder risk. This leads to consider attentional bias and response inhibition as core mechanisms in obesity and as possible targets for new therapeutic strategy.

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.