‘Food addiction’ and its association with a dopaminergic multilocus genetic profile

5-Methoxy-2-aminoindane Reverses Diet-Induced Obesity and Improves Metabolic Parameters in Mice: A Potential New Class of Antiobesity Therapeutics

The escalating prevalence of obesity and its related disorders represents a daunting global health challenge. Unfortunately, current pharmacological interventions for obesity remain limited and are often associated with debilitating side effects. Against this backdrop, the psychoactive aminoindane derivative 5-methoxy-2-aminoindane (MEAI) has gained considerable attention for its ability to induce a pleasurable, alcohol-like sensation while curbing alcohol consumption. Given the potential impact of MEAI on food addiction and energy homeostasis, we examined its metabolic efficacy on appetite regulation, obesity, and related comorbidities under acute and chronic settings, utilizing a mouse model of diet-induced obesity (DIO). Our results demonstrated that MEAI treatment significantly reduced DIO-induced overweight and adiposity by preserving lean mass and decreasing fat mass. Additionally, MEAI treatment exhibited positive effects on glycemic control by attenuating DIO-induced hyperglycemia, glucose intolerance, and hyperinsulinemia. Furthermore, MEAI reduced DIO-induced hepatic steatosis by decreasing hepatic lipid accumulation and lowering liver triglyceride and cholesterol levels, primarily by inhibiting de novo lipid synthesis. Metabolic phenotyping revealed that MEAI increased energy expenditure and fat utilization while maintaining food consumption similar to that of the vehicle-treated group. Lastly, MEAI normalized voluntary locomotion actions without any overstimulatory effects. These findings provide compelling evidence for the antiobesity effects of MEAI treatment and call for further preclinical testing. In conclusion, our study highlights the potential of MEAI as a novel therapeutic approach for treating obesity and its associated metabolic disorders, offering hope for the development of new treatment options for this global health challenge.

Association between hedonic hunger and body mass index in adults: A systematic review and meta-analysis

Hedonic hunger has been proposed as one of the important causes of obesity in recent years. In the present study, we systematically reviewed and meta-analyzed the relationship between hedonic hunger and body mass index (BMI) in healthy adults. PubMed, Web of Science, and Scopus were searched until January 19, 2023. All English-language original observational studies conducted on healthy adult subjects, which used the Power of Food Scale (PFS) to evaluate hedonic hunger were included. Quality assessment was done using the Joanna Briggs Institute checklist, and StataMP-17 software was used for the meta-analysis. After screening, 25 observational studies with a total of 14457 participants were included. Twenty-four studies were cross-sectional, and one was a cohort study. Twenty-two studies examined both sexes, two studies were conducted only on women, and one study conducted analysis separately on men and women. The results of the meta-analysis showed a positive and significant association between hedonic hunger and BMI with a small effect size (r = 0.13, 95% CI: 0.08, 0.18). In addition, a positive significant association was observed between subscales of PFS ("food available", "food present", and "food tasted") and BMI. The association between hedonic hunger and BMI was not affected by the results of meta-regression analysis of %female, mean age & BMI, and sample size. In conclusion, there was a positive significant association between hedonic hunger and BMI, but the effect size was weak. Considering the low quality of included studies, we need longitudinal design studies considering the association between these two variables as a primary outcome for a more accurate conclusion.

Development of the modified Highly Processed Food Withdrawal Scale (mProWS)

The Highly Processed Food Withdrawal Scale (ProWS) is a 29-item measure that operationalizes physical and psychological indicators of withdrawal symptoms associated with cutting down on the consumption of ultra-processed foods. The current study developed a briefer 7-item version of the ProWS (modified ProWS; mProWS) using the participant sample from the ProWS validation paper (n = 231). Then, in an independent sample recruited from Amazon Mechanical Turk, 244 participants (55.3% females) completed the mProWS, the ProWS, and measures of eating-related constructs in order to evaluate the psychometric properties of the mProWS, relative to the ProWS. The mProWS and the ProWS performed similarly on indexes of reliability, convergent validity with addictive-like eating behavior (e.g., Yale Food Addiction Scale 2.0 symptom count), discriminant validity with distinct measures (e.g., cognitive desire to restrict food consumption), and incremental validity evidenced by associations with weight cycling above and beyond body mass index (BMI) and YFAS 2.0 symptoms. The mProWS may be an appropriate choice for studies with higher participant burden (e.g., ecological momentary assessment) to assess withdrawal symptoms in real-time when they occur in response to cutting down on ultra-processed foods.

The Association between Grazing and Food Addiction: The Italian Version of the Repetitive Eating Questionnaire (Rep(Eat)-Q) and Its Relationships with Food Addiction Criteria

BACKGROUND

Among the dysfunctional eating behaviors associated with excessive food intake, a construct that is gaining increasing attention is grazing-the constant, continuous, compulsive, and repetitive consumption of small/moderate amounts of food. Furthermore, in some cases, grazing seems to indicate a dependence on food and/or eating. Currently, the Repetitive Eating Questionnaire (Rep(Eat)-Q) appears to be the only questionnaire that comprehensively measures grazing, including its repetitive and compulsive eating component. Therefore, in a sample of individuals with severe obesity, the objective of this study was twofold: (A) to evaluate the psychometric properties of the Italian version of the Rep(Eat)-Q, and (B) to analyze the association between grazing and food addiction (FA).

METHOD

A cross-sectional research design was used. A total of 402 inpatients with severe obesity (BMI > 35) were recruited. Participants underwent a series of questionnaires to investigate structural validity and convergent validity and association with FA criteria.

RESULTS

The factorial structure of the Rep(Eat)-Q is robust and showed fit indexes: CFI = 0.973; RMSEA = 0.074; 90%CI [0.056-0.091]; and SRMR = 0.029. Also, it exhibited good internal consistency and convergent validity. Furthermore, logistic regression analysis highlights a specific association between certain FA criteria and grazing.

CONCLUSIONS

The Rep(Eat)-Q can be considered to be a concise, robust, reliable, and statistically sound tool to assess repetitive eating, specifically grazing. Its strong psychometric properties offer significant advantages for both research and clinical applications. Furthermore, in a sample of individuals with severe obesity, the results suggest that individuals with problematic grazing exhibit a typical behavioral profile of subjects with FA, indicating that FA can manifest through problematic grazing as well.

Dopaminergic dysfunction: Role for genetic & epigenetic testing in the new psychiatry

Reward Deficiency Syndrome (RDS), particularly linked to addictive disorders, costs billions of dollars globally and has resulted in over one million deaths in the United States (US). Illicit substance use has been steadily rising and in 2021 approximately 21.9% (61.2 million) of individuals living in the US aged 12 or older had used illicit drugs in the past year. However, only 1.5% (4.1 million) of these individuals had received any substance use treatment. This increase in use and failure to adequately treat or provide treatment to these individuals resulted in 106,699 overdose deaths in 2021 and increased in 2022. This article presents an alternative non-pharmaceutical treatment approach tied to gene-guided therapy, the subject of many decades of research. The cornerstone of this paradigm shift is the brain reward circuitry, brain stem physiology, and neurotransmitter deficits due to the effects of genetic and epigenetic insults on the interrelated cascade of neurotransmission and the net release of dopamine at the Ventral Tegmental Area -Nucleus Accumbens (VTA-NAc) reward site. The Genetic Addiction Risk Severity (GARS) test and pro-dopamine regulator nutraceutical KB220 were combined to induce "dopamine homeostasis" across the brain reward circuitry. This article aims to encourage four future actionable items: 1) the neurophysiologically accurate designation of, for example, "Hyperdopameism /Hyperdopameism" to replace the blaming nomenclature like alcoholism; 2) encouraging continued research into the nature of dysfunctional brainstem neurotransmitters across the brain reward circuitry; 3) early identification of people at risk for all RDS behaviors as a brain check (cognitive testing); 4) induction of dopamine homeostasis using "precision behavioral management" along with the coupling of GARS and precision Kb220 variants; 5) utilization of promising potential treatments include neuromodulating modalities such as Transmagnetic stimulation (TMS) and Deep Brain Stimulation(DBS), which target different areas of the neural circuitry involved in addiction and even neuroimmune agents like N-acetyl-cysteine.

Multilocus Genetic Profile Reflecting Low Dopaminergic Signaling Is Directly Associated with Obesity and Cardiometabolic Disorders Due to Antipsychotic Treatment

Treatment with second-generation antipsychotics (SGAs) can cause obesity and other cardiometabolic disorders linked to D2 receptor (DRD2) and to genotypes affecting dopaminergic (DA) activity, within reward circuits. We explored the relationship of cardiometabolic alterations with single genetic polymorphisms DRD2 rs1799732 (NG_008841.1:g.4750dup -> C), DRD2 rs6277 (NG_008841.1:g.67543C>T), COMT rs4680 (NG_011526.1:g.27009G>A), and VNTR in both DRD4 NC_000011.10 (637269-640706) and DAT1 NC_000005.10 (1392794-1445440), as well as with a multilocus genetic profile score (MLGP). A total of 285 psychiatric patients treated with SGAs for at least three months were selected. Cardiometabolic parameters were classified according to ATP-III and WHO criteria. Blood samples were taken for routinely biochemical assays and PCR genotyping. Obesity (BMI, waist (W)), high diastolic blood pressure (DBP), and hypertriglyceridemia (HTG) were present in those genetic variants related to low dopaminergic activity: InsIns genotype in rs1799732 (BMI: OR: 2.91 [1.42-5.94]), DRD4-VNTR-L allele (W: OR: 1.73 [1.04-2.87]) and 9R9R variant in DAT1-VNTR (W: OR: 2.73 [1.16-6.40]; high DBP: OR: 3.33 [1.54-7.31]; HTG: OR: 4.38 [1.85-10.36]). A low MLGP score indicated a higher risk of suffering cardiometabolic disorders (BMI: OR: 1.23 [1.05-1.45]; W: OR: 1.18 [1.03-1.34]; high DBP: OR: 1.22 [1.06-1.41]; HTG: OR: 1.20 [1.04-1.39]). The MLGP score was more sensitive for detecting the risk of suffering these alterations. Low dopaminergic system function would contribute to increased obesity, BDP, and HTG following long-term SGA treatment.

Neural differences of food-specific inhibitory control in people with healthy vs higher BMI

Consistent with the idea that deficits in inhibition limit resistance to tempting, tasty, high-calorie foods, and might result in a higher BMI, we test whether people with higher BMIs (BMI >25 kg/m²) present inefficient inhibitory control over food-related responses. To unpack this association, we also examine individual differences in the neural mechanisms of food inhibitory control in healthy vs higher BMI individuals. We test these aspects with a sample of 109 participants (49 with higher BMI and 60 with healthy BMI) and the food stop-signal task, which was used to examine individuals' inhibitory control. Results demonstrated that people with higher BMI had significantly poorer food inhibitory control than healthy BMI individuals. fMRI results showed that, in both Go (Go_food vs Go_nature) and Stop conditions (Stop_food vs Stop_nature), compared to healthy BMI individuals, individuals with higher BMI had lower activation in the superior frontal gyrus, precuneus, precentral gyrus, and supramarginal gyrus in the food stimulus condition. Moreover, ROI analysis results showed that under the Stop_food condition, the activation in the inferior frontal gyrus in the higher BMI group was significantly negatively correlated with inhibitory control abilities. These results suggest that people with a higher BMI have limited ability to inhibit food impulsions, and that the prefrontal regions and parietal cortex may contribute to the progression of inhibitory control limitations in relation to food.

No association of the dopamine D2 receptor genetic bilocus score (rs1800497/rs1799732) on food addiction and food reinforcement in Chilean adults

Purpose: Different systems regulate food intake. In the reward system, dopamine (DA) is the main neurotransmitter, and a variety of genetic variants (rs1799732 and rs1800497) are associated with addiction. Addiction is a highly polygenic disease, where each allelic variant adds a small amount of vulnerability. Polymorphisms rs1799732 and rs1800497 are associated with eating behavior and hedonic hunger, but links to food addiction remain unclear.

Aim: To evaluate the association between the bilocus profile (rs1799732-rs1800497) of the dopaminergic pathway with food reinforcement and food addiction in Chilean adults.

Methods: A cross-sectional study recruited a convenience sample of 97 obese, 25 overweight, and 99 normal-weight adults (18–35 years). Anthropometric measurements were performed by standard procedures and eating behavior was assessed using the: Food Reinforcement Value Questionnaire (FRVQ) and Yale Food Addiction scale (YFAS). The DRD2 genotypes were determined by TaqMan assays (rs1800497 and rs1799732). A bilocus composite score was calculated.

Results: In the normal weight group, individuals who were heterozygous for the rs1977932 variant (G/del) showed higher body weight (p-value 0.01) and abdominal circumference (p-value 0.01) compared to those who were homozygous (G/G). When analyzing rs1800497, a significant difference in BMI was observed for the normal weight group (p-value 0.02) where heterozygous showed higher BMI. In the obese group, homozygous A1/A1 showed higher BMI in comparison to A1/A2 and A2/A2 (p-value 0.03). Also, a significant difference in food reinforcement was observed in the rs1800497, where homozygous for the variant (A1A1) show less reinforcement (p-value 0.01).In relation to the bilocus score in the total sample, 11% showed “very low dopaminergic signaling”, 24.4% were “under”, 49.7% showed “intermediate signaling”, 12.7% showed “high” and 1.4% showed “very high”. No significant genotypic differences were observed in food reinforcement and food addiction by bilocus score.

Conclusions: The results indicate that the genetic variants rs1799732 and rs1800497 (Taq1A) were associated with anthropometric measurements but not with food addiction or food reinforcement in Chilean university students. These results suggest that other genotypes, such as rs4680 and rs6277, which affect DA signaling capacity through a multilocus composite score, should be studied. Level V: Evidence obtained from a cross-sectional descriptive study.

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.

Examining the biological mechanisms of human mental disorders resulting from gene-environment interdependence using novel functional genomic approaches

We explore how functional genomics approaches that integrate datasets from human and non-human model systems can improve our understanding of the effect of gene-environment interplay on the risk for mental disorders. We start by briefly defining the G-E paradigm and its challenges and then discuss the different levels of regulation of gene expression and the corresponding data existing in humans (genome wide genotyping, transcriptomics, DNA methylation, chromatin modifications, chromosome conformational changes, non-coding RNAs, proteomics and metabolomics), discussing novel approaches to the application of these data in the study of the origins of mental health. Finally, we discuss the multilevel integration of diverse types of data. Advance in the use of functional genomics in the context of a G-E perspective improves the detection of vulnerabilities, informing the development of preventive and therapeutic interventions.

Why haven't we solved the addiction crisis?

The current addiction crisis has destroyed a multitude of lives, leaving millions of fatalities worldwide in its wake. At the same time, various governmental agencies dedicated to solving this seemingly never-ending dilemma have not yet succeeded or delivered on their promises. We understand that addictive behavioral seeking is a multi-faceted neurobiological and spiritually complicated phenomenon. However, although the substitution replacement approach, especially to treat Opioid Use Disorder (OUD), has importance for harm reduction in the short term, it does not bring about a harm-free recovery or prevention. Instead, we propose a promising novel approach that uses genetic risk testing with induction of dopamine homeostasis and an objective Brain Health Check during youth. Our model involves a six-hit approach known as the "Reward Dysregulation Syndrome Solution System," which can identify addiction risk and target the root cause of addiction, dopamine dysregulation. While we applaud all past sophisticated neurogenetic and neuropharmacological research, our opinion is that in the long term, addiction scientists and clinicians might characterize preaddiction using tests; for example, administering the validated RDSQuestionarre29, genetic risk assessment, a modified brain health check, or diagnostic framing of mild to moderate Substance Use Disorder (SUD). The preaddiction concept could incentivize the development of interventions to prevent addiction from developing in the first place and target and treat neurotransmitter imbalances and other early indications of addiction. WC 222.

Reward Deficiency Syndrome (RDS) Surprisingly Is Evolutionary and Found Everywhere: Is It "Blowin' in the Wind"?

Reward Deficiency Syndrome (RDS) encompasses many mental health disorders, including a wide range of addictions and compulsive and impulsive behaviors. Described as an octopus of behavioral dysfunction, RDS refers to abnormal behavior caused by a breakdown of the cascade of reward in neurotransmission due to genetic and epigenetic influences. The resultant reward neurotransmission deficiencies interfere with the pleasure derived from satisfying powerful human physiological drives. Epigenetic repair may be possible with precision gene-guided therapy using formulations of KB220, a nutraceutical that has demonstrated pro-dopamine regulatory function in animal and human neuroimaging and clinical trials. Recently, large GWAS studies have revealed a significant dopaminergic gene risk polymorphic allele overlap between depressed and schizophrenic cohorts. A large volume of literature has also identified ADHD, PTSD, and spectrum disorders as having the known neurogenetic and psychological underpinnings of RDS. The hypothesis is that the true phenotype is RDS, and behavioral disorders are endophenotypes. Is it logical to wonder if RDS exists everywhere? Although complex, “the answer is blowin’ in the wind,” and rather than intangible, RDS may be foundational in species evolution and survival, with an array of many neurotransmitters and polymorphic loci influencing behavioral functionality.

A literature review of dopamine in binge eating

OBJECTIVE

Binge eating, a core diagnostic symptom in binge eating disorder and bulimia nervosa, increases the risk of multiple physiological and psychiatric disorders. The neurotransmitter dopamine is involved in food craving, decision making, executive functioning, and impulsivity personality trait; all of which contribute to the development and maintenance of binge eating. The objective of this paper is to review the associations of dopamine levels/activities, dopamine regulator (e.g., dopamine transporter, degrading enzymes) levels/activities, and dopamine receptor availability/affinity with binge eating.

METHODS

A literature search was conducted in PubMed and PsycINFO to obtain human and animal studies published since 2010.

RESULTS

A total of 31 studies (25 human, six animal) were included. Among the human studies, there were 12 case-control studies, eight randomized controlled trials, and five cross-sectional studies. Studies used neuroimaging (e.g., positron emission tomography), genetic, and pharmacological (e.g., dopamine transporter inhibitor) techniques to describe or compare dopamine levels/activities, dopamine transporter levels/activities, dopamine degrading enzyme (e.g., catechol-O-methyltransferase) levels/activities, and dopamine receptor (e.g., D1, D2) availability/affinity among participants with and without binge eating. Most human and animal studies supported an altered dopaminergic state in binge eating (26/31, 83.9%); however, results were divergent regarding whether the altered state was hyperdopaminergic (9/26, 34.6%) or hypodopaminergic (17/26, 65.4%). The mixed findings may be partially explained by the variability in sample characteristics, study design, diagnosis criteria, and neuroimaging/genetic/pharmacological techniques used. However, it is possible that instead of being mutually exclusive, the hyperdopaminergic and hypodopaminergic state may co-exist, but in different stages of binge eating or in different individual genotypes.

CONCLUSIONS

For future studies to clarify the inconsistent findings, a homogenous sample that controls for confounders that may influence dopamine levels (e.g., psychiatric diseases) is preferable. Longitudinal studies are needed to evaluate whether the hyper- and hypo-dopaminergic states co-exist in different stages of binge eating or co-exist in individual phenotypes. Binge eating is characterized by eating a large amount of food in a short time and a feeling of difficulty to stop while eating. Binge eating is the defining symptom of binge eating disorder and bulimia nervosa, both of which are associated with serious health consequences. Studies have identified several psychological risk factors of binge eating, including a strong desire for food, impaired cognitive skills, and distinct personality traits (e.g., quick action without careful thinking). However, the physiological markers of binge eating remain unclear. Dopamine is a neurotransmitter that is heavily involved in feeding behavior, human motivation, cognitive ability, and personality. Therefore, dopamine is believed to play a critical role in binge eating. This review synthesized study findings related to the levels and activities of dopamine, dopamine regulators, and dopamine receptors in the context of binge eating. The primary finding is that most studies that used neuroimaging, genetic, or drug techniques found an altered dopaminergic state related to binge eating. However, the literature is inconsistent concerning the direction of the alteration. Considering the mixed findings and the limitations in study design, future studies, especially those that include repeated measurements, are needed to clarify the role of dopamine in binge eating.

Impulsivity and neural mechanisms that mediate preference for immediate food rewards in people with vs without excess weight

People with excess weight (overweight or obese; body mass index [BMI]>25) are generally characterized as impulsive with regards to food. However, the underlying brain mechanisms of this impulsivity are not fully understood. As such, this study aims at understanding the neural mechanisms underlying impulsivity toward food rewards, as well as differences in delay discounting patterns for hypothetical food between people with vs without excess weight. To this end, participants (79 college students, 33 with excess weight and 46 without) performed a food delay discounting task and completed questionnaires related to food addiction and impulsivity. In the task, we manipulated the magnitude of immediate and delayed rewards and employed event-related fMRI design to measure brain activity. The results showed that people with excess weight, compared to those without, were more impulsive and presented a lower probability of choosing delayed rewards. The higher the BMI was, the lower the probability of choosing delayed rewards was. People with excess weight also had higher impulsivity scores than people with no excess weight. Moreover, people with excess weight had less activation in executive function areas such as the anterior cingulate gyrus, the frontal pole, and the inferior frontal gyrus in both difficult and easy decision-making conditions. These results suggest that hypo-activation of executive function areas may contribute to the progression of decision impulsivity in relation to food, which in turn is associated with excess weight.

The Assessment of Food Addiction and the Yale Food Addiction Scale in Bariatric Surgery Populations

Food addiction (FA) appears among bariatric weight loss surgery candidates who struggle to control the intake of hyperpalatable/refined foods have high rates of psychopathology and related health problems. Despite this, prevalence rates of FA in the bariatric sector are reported as low or variable. We investigated the prevalence of FA and the applicability of conventionally used metrics for 166 pre-surgery candidates from a weight management centre (USA) and a major metropolitan hospital (Australia). Self-report measures assessed FA (Yale Food Addiction Scale (YFAS)), body mass index (BMI), disordered eating, addictive personality, psychopathology, and diet. Consistent with prior research, standard YFAS scoring, requiring the endorsement of a distress/impairment (D/I) criterion (FA + D/I), yielded a FA prevalence rate of 12.7%, compared to 37.3% when D/I was omitted (FA − D/I). We compared profiles for those with FA using each scoring method against those ‘without’, who did not meet a minimum of three YFAS symptoms (non-FA ≤ 2). Both methods differentiated those with and without FA on addictive traits, disordered eating and hyperpalatable food consumption. Only FA + D/I differentiated markers of psychological distress or impairment, including depression, anxiety and quality of life. Results indicate a need for further FA research in bariatric settings.

Highly processed food addiction: A concept analysis

AIM

This concept analysis aims to clarify the highly processed food addiction (HPFA) concept and discuss its implications for treating obesity.

BACKGROUND

Emerging empirical evidence suggests addictive-like eating may contribute to obesity in some individuals, increasing interest in HPFA's role in obesity. Clarifying the HPFA concept will aid in developing individualized interventions for patients with obesity and HPFA.

DESIGN

This concept analysis followed Walker and Avant's approach. The case studies are of participants in a study that included individuals with and without HPFA (Yale Food Addiction Scale 2.0-diagnosed).

DATA SOURCE

We searched PubMed, CINAHL, PsychInfo, and Ebscohost databases. Keywords were "food addiction" and "food addiction concept."

REVIEW METHODS

Criteria included recent reviews and empirical studies that measured HPFA and focused on HPFA characteristics and/or treatment implications.

RESULTS

The model case displayed all 11-substance use disorder (SUD) symptoms and clinical significance, supporting a severe HPFA diagnosis. The contrary case was negative for all YFAS 2.0 symptoms and clinical significance and did not eat compulsively or experience cravings. The borderline case met the minimum symptom criteria for severe HPFA but not clinical significance. Clinical interviews may help determine whether such individuals truly exhibit addictive-like eating behaviors.

CONCLUSIONS

Growing empirical evidence and our case studies support the HPFA concept and the utility of the YFAS/YFAS 2.0 for identifying a distinct subset of individuals with overweight/obesity who may benefit from interventions developed to treat established SUDs. Future research should examine HPFA separately and in relation to obesity and eating disorders and include longitudinal studies and gender-balanced samples.

Food Addiction and Its Relationship to Weight- and Addiction-Related Psychological Parameters in Individuals With Overweight and Obesity

Background and Aims: It is assumed that a relevant subgroup of individuals experiences an addiction-like eating behaviour (Food Addiction), characterized by an impaired control over eating behaviour, emotional eating and food craving. Individuals experiencing Food Addiction partially share common symptomatology with Binge-Eating-Disorder and Bulimia Nervosa. The aim of this study was to investigate the prevalence of Food Addiction, general psychopathology, and associations with weight- and addiction-related constructs in individuals with overweight and obesity, who did not suffer from Binge-Eating-Disorder or Bulimia Nervosa.

Methods:N=213 (67.1% female; M_BMI=33.35kg/m², SD_BMI=3.79kg/m²) participants who were included in a weight loss program (I-GENDO project) reported BMI and completed questionnaires before the start of the treatment. Food Addiction severity, depressive symptoms, alcohol use disorder, internet use disorder, psychological distress, impulsivity personality trait, impulsive and emotional eating behaviour, food related inhibitory control, weight bias internalization, and self-efficacy were assessed.

Results: The prevalence of Food Addiction was 15% with higher, although not statistically significant, prevalence in female (18.2%) compared to male (8.6%) participants. Food Addiction was associated with higher BMI at baseline assessment, low self-esteem, impulsive and emotional eating behaviour, weight bias internalization, and deficits in food-related inhibitory control. In addition, correlations were found between Food Addiction and severity of depressive symptoms, internet use disorder, and psychological distress.

Conclusion: A relevant subgroup of participants experiences Food Addiction even when controlling for Binge-Eating-Disorder and Bulimia Nervosa. Future studies are warranted that investigate whether Food Addiction affects treatment success.

A cross-sectional examination of reported changes to weight, eating, and activity behaviors during the COVID-19 pandemic among United States adults with food addiction

Prior studies have demonstrated the effects of the COVID-19 pandemic on weight management and lifestyle behaviors, though identification of who may be at greatest risk for negative consequences has not been fully explored. Addictive-like eating behavior, or food addiction, has been associated with an array of problematic eating behaviors, which may suggest heightened susceptibility to poorer outcomes. In this online, cross-sectional study, adults (ages 18–78; M = 42.36, SD = 13.08) living in the United States (n = 288) completed questionnaires assessing food addiction and reported changes to their weight, eating, and physical activity before and during the COVID-19 pandemic. Individuals with food addiction gained an average of 12.42 lb (5.63 kg) since March 2020, compared to an average weight gain of 2.14 lb (0.97 kg) for those without food addiction (p < .001). Linear regression analyses controlling for age and body mass index (BMI) showed that food addiction was independently associated with higher weight gain (B = 9.28, t = 4.97, p < .001), greater intake of ultra-processed foods before and during COVID-19 (B = 1.08, t = 5.71, p < .001; B = 1.18, t = 6.42, p < .001, respectively), greater attribution of their overall current eating behaviors to COVID-19 circumstances (B = 23.19, t = 4.62, p < .001), and higher distress about their overall current eating behaviors (B = −22.12, t = −2.50, p = .01). Interaction effects demonstrated that individuals with food addiction who are older may be at particularly high risk for weight gain and distress. The present research suggests that food addiction is a uniquely meaningful phenotype, beyond the effects of BMI, to identify risk for the negative consequences of COVID-19. Individuals with food addiction, particularly those who are older, may benefit from support with weight management and addictive-like eating as the COVID-19 pandemic persists and resolves.

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.

Dopaminergic Genetic Variation in Young Adolescents: Associations with Sensation-Seeking

Deficient reward functioning, including reward-related personality, is implicated in depression's etiology. A dopaminergic genetic multilocus genetic profile score (MGPS) has previously been associated with neural reward responsivity but, despite theoretical basis, has not been studied with reward-related personality. Such research is needed to elucidate associations between genetic variation and reward-related personality in a developmentally sensitive population. In the present study, we examined associations between dopaminergic MGPS's and self-report reward-related personality in two young adolescent samples aged 10-15 years old (Sample 1: N = 100 girls, 82% White, 18% Other; Sample 2: N = 141, 65 girls, 76 boys, 89.36% White, 10.64% Other) using an established MGPS and an augmented MGPS. A "mini" meta-analysis synthesized results across samples. In Sample 1, an exploratory mediation analysis intended to gauge effect size for future work tested a path between the MGPS and depression through significant reward traits. In each independent sample, both MGPS's showed significant associations with sensation-seeking but not social drive, a pattern that persisted following correction. Effect sizes of novel variants were at least as robust as established variants, suggesting their added utility. Additionally, the exploratory mediation analysis suggested no noteworthy indirect effect, but a small (R² = 0.022), statistically non-significant direct effect of the MGPS predicting prospective depressive symptoms. Results suggest that dopaminergic genetic variation is associated with the reward-related personality trait of sensation seeking but not social drive. Additional work is needed to probe whether sensation seeking may be a path through which this genetic variation confers depression risk.

Genomics and epigenomics of addiction

Recent progress in the genomics and epigenomics of addiction has contributed to improving our understanding of this complex mental disorder's etiology, filling the gap between genes, environment, and behavior. We review the behavioral genetic studies reporting gene and environment interactions that explain the polygenetic contribution to the resilience and vulnerability to develop addiction. We discuss the evidence of polymorphic candidate genes that confer susceptibility to develop addiction as well as the studies of specific epigenetic marks that contribute to vulnerability and resilience to addictive-like behavior. A particular emphasis has been devoted to the miRNA changes that are considered potential biomarkers. The increasing knowledge about the technology required to alter miRNA expression may provide promising novel therapeutic tools. Finally, we give future directions for the field's progress in disentangling the connection between genes, environment, and behavior.

A Novel Precision Approach to Overcome the "Addiction Pandemic" by Incorporating Genetic Addiction Risk Severity (GARS) and Dopamine Homeostasis Restoration

This article describes a unique therapeutic precision intervention, a formulation of enkephalinase inhibitors, enkephalin, and dopamine-releasing neuronutrients, to induce dopamine homeostasis for detoxification and treatment of individuals genetically predisposed to developing reward deficiency syndrome (RDS). The formulations are based on the results of the addiction risk severity (GARS) test. Based on both neurogenetic and epigenetic evidence, the test evaluates the presence of reward genes and risk alleles. Existing evidence demonstrates that the novel genetic risk testing system can successfully stratify the potential for developing opioid use disorder (OUD) related risks or before initiating opioid analgesic therapy and RDS risk for people in recovery. In the case of opioid use disorders, long-term maintenance agonist treatments like methadone and buprenorphine may create RDS, or RDS may have been in existence, but not recognized. The test will also assess the potential for benefit from medication-assisted treatment with dopamine augmentation. RDS methodology holds a strong promise for reducing the burden of addictive disorders for individuals, their families, and society as a whole by guiding the restoration of dopamine homeostasisthrough anti-reward allostatic neuroadaptations. WC 175.

No association between dopaminergic polymorphisms and response to treatment of binge-eating disorder

BACKGROUND

The genetics of binge-eating disorder (BED) is an emerging topic, with dopaminergic genes being implicated in its etiology due to the role that dopamine (DA) plays in food reward sensitivity and self-regulation of eating behavior. However, no study to date has examined if DA genes influence response to behavioral treatment of BED.

OBJECTIVE

The primary objective of this study was to examine the ability of DA-associated polymorphisms to predict BED treatment response measured using binge frequency over 12 months. As secondary objectives, this study examined cross-sectional relationships between these polymorphisms and anthropometrics in women living with and without BED and obesity.

METHODS

Women aged 18-64 years old were genotyped for the DA-related SNPs DRD2/ANKK1 Taq1A (rs1800497) and COMT (rs4680), as well as the DA-related uVNTRs DAT-1 (SLC6A3) and MAO-A. A multi-locus DA composite score was formed from these 4 polymorphisms using genotypes known to have a functional impact resulting in modified DA signaling. Binge frequency (Eating Disorder Examination - Interview) and body composition (Tanita BC-418) were assessed in a pre-post analysis to examine genetic predictors of treatment response in women living with obesity and BED. Secondary data analysis was conducted on a cross-sectional comparison of three groups of women enrolled in trial group treatment for BED: women living with obesity and BED (n = 72), obesity without BED (n = 27), and normal-weight without BED (n = 45).

RESULTS

There were no significant genotype × time interactions related to anthropometrics or binge frequency for any individual DA genotypes, or to the composite score reflecting DA availability. At baseline, there were no significant between-group differences in frequencies of DA-related alleles, nor were there associations between genotypes and anthropometrics.

CONCLUSIONS

Our study found no evidence to suggest that the DRD2/ANKK1 Taq1A, COMT, MAO-A, or DAT-1 polymorphisms are associated with response to behavioral intervention for BED as measured by changes in binge frequency. Future studies should examine a greater variety of dopaminergic polymorphisms, other candidate genes that target other neurotransmitter systems, as well as examine their impact on both behavioral and pharmacological-based treatment for BED.

Structural validity, measurement invariance, reliability and diagnostic accuracy of the Italian version of the Yale Food Addiction Scale 2.0 in patients with severe obesity and the general population

PURPOSE

To examine the structural validity, measurement invariance, reliability, and some other psychometrical properties of the Italian version of the Yale Food Addiction Scale 2 (I-YFAS 2.0) in patients with severe obesity and the general population.

METHODS

704 participants-400 inpatients with severe obesity and 304 participants enrolled from the general population-completed the I-YFAS 2.0 and questionnaires measuring eating disorder symptoms. A first confirmatory factor analysis (CFA) tested a hierarchical structure in which each item of the I-YFAS 2.0 loaded onto one of the twelve latent symptoms/criteria which loaded onto a general dimension of Food Addiction (FA). The second CFA tested a first-order structure in which symptoms/criteria of FA simply loaded onto a latent dimension. Measurement invariance (MI) between the group of inpatients with severe obesity and the sample from the general population was also tested. Finally, convergent validity, test-retest reliability, internal consistency, and prevalence analyses were performed.

RESULTS

CFAs confirmed the structure for the I-YFAS 2.0 for both the hierarchical structure and the first-order structure. Configural MI and strong MI were reached for hierarchical and the first-order structure, respectively. Internal consistencies were shown to be acceptable. Prevalence of FA was 24% in the group of inpatients with severe obesity and 3.6% in the sample from the general population.

CONCLUSIONS

The I-YFAS 2.0 represents a valid and reliable questionnaire for the assessment of FA in both Italian adult inpatients with severe obesity and the general population, and is a psychometrically sound tool for clinical as well as research purposes.

LEVEL OF EVIDENCE

Level V, descriptive study.

Associations of the ANKK1 and DRD2 gene polymorphisms with overweight, obesity and hedonic hunger among women from the Northwest of Iran

BACKGROUND

Pleasure from palatable foods can stimulate hedonic eating and, therefore, might be a major culprit for obesity. Dopamine receptor polymorphisms, especially variants in the genes regulating the D2 receptor, including ANKK1 and DRD2, are the prime candidates for assessing the individual differences in hedonic eating. This study was carried out to investigate the possible associations of the T (rs1800497) and Del (rs1799732) alleles with body mass index (BMI) and hedonic hunger among Iranian Azeri women.

METHODS

A total of 372 healthy overweight/obese subjects (BMI ≥ 25 kg/m²) and 159 normal weight individuals (BMI 18.5-24.9 kg/m²) were genotyped for the polymorphisms of ANNK1 and DRD2 genes using PCR-RFLP. BMI and hedonic hunger were also evaluated.

RESULTS

Three hundred and sixty-three (68.36%), 152 (28.63%), and 16 (3.01%) of the participants had CC, CT, and TT genotypes for ANNK1 gene, respectively. Of 515 samples genotyped for DRD2 gene, 315 (60.51%), 173 (33.59%), and 27 (5.24%) had Ins/Ins, Ins/Del, and Del/Del genotypes, respectively. The genotype and genotype frequencies were significantly different between the groups (p = 0.04). Significant differences were observed between the T+ genotype (TT + TC) and the T- genotype (CC) regarding the BMI and hedonic hunger scores (p < 0.05). In addition, Del+ group (Del/Del + Ins/Del) had higher BMI and hedonic hunger scores compared to Del- group (Ins/Ins) (p < 0.05).

CONCLUSIONS

Our findings showed that the frequencies of T and Del alleles were greater in the overweight/obese individuals. Also, the polymorphism of ANKK1 (rs1800497) and polymorphism of the DRD2 gene (rs1799732) showed significant associations with BMI and hedonic hunger.

LEVEL OF EVIDENCE

Level III, case-control study.

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.

Multidimensional elements of impulsivity as shared and unique risk factors for food addiction and alcohol misuse

Food addiction (FA) and alcohol misuse tend to co-occur, which suggests shared factors in the etiology and persistence of these health behaviors. One shared factor that has been linked to both is impulsivity, a multidimensional construct reflecting multiple facets of self-regulatory capacity. However, co-occurrence also raises issues of possible confounding if both domains are not considered concurrently, and the intersection between FA, alcohol misuse, and impulsivity has not been well characterized empirically. Therefore, the current study examined the intersection of FA, alcohol consequences, and multiple indicators of impulsivity. Participants were emerging adults reporting regular heavy episodic drinking recruited from Hamilton, Ontario (N = 730; ages 19.5-23). Participants completed measures of FA, alcohol problems, impulsive personality traits (i.e., Barratt Impulsiveness Scales, UPPS-P Impulsive Behavior Scales), impulsive choice (i.e., delay discounting), impulsive action (i.e., Go/NoGo task). Findings revealed a significant association between FA and alcohol-related consequences and both shared similar associations with specific impulsive personality traits (Positive and Negative Urgency, Lack of Premeditation, Motor and Attentional Impulsivity). However, alcohol-related consequences were uniquely associated with other impulsive personality traits (Lack of Perseverance, Sensation Seeking, Non-planning impulsivity) and impulsive choice, and FA was uniquely associated with impulsive action. Beyond alcohol-related consequences, FA was associated with additional variance in measures of impulsive personality traits (Positive and Negative Urgency, Lack of Premeditation, Motor Impulsivity, and Attentional Impulsivity) and impulsive action, but not impulsive choice. Overall, the current study reveals several common self-regulatory processes associated with both adverse drinking consequences and FA, and that the risk of inadvertent confounding appears to be limited.

Longitudinal Changes in Food Addiction Symptoms and Body Weight among Adults in a Behavioral Weight-Loss Program

Interest in food addiction (FA) has increased, but little is known about its clinical implications or potential treatments. Using secondary analyses from a randomized controlled trial, we evaluated the associations between changes in FA, body weight, and “problem food” consumption during a 22-month behavioral weight-loss program consisting of an initial four-month in-person intervention, 12-month extended-care, and six-month follow-up (n = 182). Food addiction was measured using the Yale Food Addiction Scale. “Problem foods” were identified from the literature and self-reporting. Multilevel modeling was used as the primary method of analysis. We hypothesized that reductions in problem food consumption during the initial treatment phase would be associated with long-term (22-month) FA reductions. As expected, we found that reductions in problem foods were associated with greater initial reductions in FA symptoms; however, they were also associated with a sharper rebound in symptoms over time (p = 0.016), resulting in no significant difference at Month 22 (p = 0.856). Next, we hypothesized that long-term changes in FA would be associated with long-term changes in body weight. Although both FA and weight decreased over time (ps < 0.05), month-to-month changes in FA were not associated with month-to-month changes in weight (p = 0.706). Instead, higher overall FA (i.e., mean scores over the course of the study) were associated with less weight loss (p = 0.008) over time. Finally, we hypothesized that initial reductions in problem food consumption would be associated with long-term reductions in weight, but this relationship was not significant (ps > 0.05). Given the complexity of the findings, more research is needed to identify interventions for long-term changes in FA and to elucidate the associations between problem foods, FA, and weight.

Prisoners of Addictive Cues: Biobehavioral Markers of Overweight and Obese Adults with Food Addiction

Obesity is associated with food and eating addiction (FA), but the biobehavioral markers of this condition are poorly understood. To characterize FA, we recruited 18 healthy controls and overweight/obese adults with (n = 31) and without (n = 17) FA (H-C, FAOB, NFAOB, respectively) to assess alpha brain asymmetry at rest using electroencephalogram; event-related potentials following exposure to high-calorie food (HCF), low-calorie food (LCF), and nonfood (NF) images in a Stroop paradigm; reaction time reflective of the Stroop bias; and symptoms of depression and disordered eating behavior. The FAOB group had the greatest emotional and uncontrollable eating, depressive, and binge-eating symptoms. The FAOB group displayed lower resting left alpha brain asymmetry than that of the NFAOB group. Differently from the other groups, the FAOB group presented attenuated Stroop bias following exposure to HCF relative to NF images, as well as a lower late positive potential component (LPPb; 450-495 ms) in both frontal and occipital regions. In the total cohort, a correlation was found between the Stroop bias and the LPPb amplitude. These results point to biobehavioral hypervigilance in response to addictive food triggers in overweight/obese adults with FA. This resembles other addictive disorders but is absent in overweight/obesity without FA.

Binge Eating and Addictive-Like Behaviours in Males and Females

INTRODUCTION

Binge eating is a common behaviour that is strongly linked to both obesity and eating disorder. There is evidence that binge eating commonly co-occurs with other problematic and addictive-like behaviours; however, this has not been explored systematically. The present study aimed to examine the relationship between binge eating, body weight, disordered eating behaviours and associated addictive-like behaviours, with particular attention paid to gender differences.

METHOD

A community sample (N = 500; 75% female, M_age = 32.5 years) reported disordered eating behaviours (i.e. binge eating, purging, restriction of eating, compulsive exercise), body mass index (BMI), food addiction, starvation addiction, exercise dependence, tobacco use and alcohol consumption.

RESULTS

42% of females and 21% of males reported binge eating during the past four weeks. Binge eating was significantly associated with all investigated behaviours in females, and with purging, compulsive exercise and overweight/obesity in males. Controlling for BMI, self-starvation predicted binge eating in males (OR = 1.07), while food addiction (OR = 1.73) and alcohol dependence (OR = 1.11) predicted binge eating in females.

CONCLUSIONS

The multiple associations between binge eating and addictive-like behaviors supports broad screening and generalized prevention efforts. Prevention efforts should reflect gender differences.

Measurement, prevalence, and psychological risk factors associated with addictive food consumption: Development of a new food addiction scale and evidence from a national largescale sample

BACKGROUND AND AIMS

To date, a number of studies have investigated the prevalence and correlates of addictive food consumption. However, these studies have mostly relied on models that comprised a narrow range of variables in often small and heterogenous samples. The purpose of the present study was to comprehensively examine the measurement aspects, the prevalence, and the psychological correlates of addictive eating among a largescale national sample of Turkish adults.

METHOD

Participants (N = 24,380, 50% men, Mage = 31.79 years, age range = 18-81 years) completed a battery of tests including the Food Addiction Risk Questionnaire (FARQ), the Brief Symptom Inventory, the Toronto Alexithymia Scale, the Positive and Negative Affect Schedule, and the Experiences in Close Relationships-Revised.

RESULTS

According to analyses conducted, the FARQ had a uni-dimensional factor structure. Based on Item Response Theory (IRT) calculated cut-off scores, 2.3% of the participants were at risk of addictive eating patterns, whilst criteria varied in their discriminating ability. The correlates of addictive food consumption were being male, being younger, having lower education, presenting with higher alcohol use, psychiatric symptoms, alexithymia, positive/negative affect, and anxious attachment.

CONCLUSION

These results suggest that a minority of Turkish community are at risk for addictive food consumption and that adverse psychological states promote this problematic behavior.

A Behavioral Genetic Model of the Mechanisms Underlying the Link Between Obesity and Symptoms of ADHD

Objective: The ADHD-obesity link has been suggested to result from a shared underlying basis of suboptimal dopamine (DA); however, this theory conflicts evidence that an amplified DA signal increases the risk for overeating and weight gain. A model was tested in which ADHD symptoms, predicted by hypodopaminergic functioning in the prefrontal cortex, in combination with an enhanced appetitive drive, predict hedonic eating and, in turn, higher body mass index (BMI). Method: DRD2 and DRD4 markers were genotyped. The model was tested using structural equation modeling in a nonclinical sample (N = 421 adults). Results: The model was a good fit to the data. Controlling for education, all parameter estimates were significant, except for the DRD4-ADHD symptom pathway. The significant indirect effect indicates that overeating mediated the ADHD symptoms-BMI association. Conclusion: Results support the hypothesis that overeating and elevated DA in the ventral striatum-representative of a greater reward response-contribute to the ADHD symptom-obesity relationship.

Transcranial Magnetic Stimulation Meets Virtual Reality: The Potential of Integrating Brain Stimulation With a Simulative Technology for Food Addiction

The aim of this perspective is to propose and discuss the integration of transcranial magnetic stimulation (TMS) over the dorsolateral prefrontal cortex with virtual reality (VR) food exposure for therapeutic interventions for food addiction. "Food addiction" is a dysfunctional eating pattern which is typically observed in eating disorders (ED) such as bulimia nervosa and binge eating disorder. Food addiction has been compared to substance use disorder due to the necessity of consuming a substance (food) and the presence of a dependence behavior. In recent years, VR has been applied in the treatment of ED because it triggers psychological and physiological responses through food exposure in place of real stimuli. Virtual reality-Cue exposure therapy has been proven as a valid technique for regulating anxiety and food craving in ED. More, TMS has been proven to modulate circuits and networks implicated in neuropsychiatric disorders and is effective in treating addiction such as nicotine craving and consumption and cocaine use disorder. The combination of a simulative technology and a neurostimulation would presumably provide better improvement compared to a single intervention because it implies the presence of both cognitive and neuropsychological techniques. The possible advantage of this approach will be discussed in the perspective.

Food Addiction Mediates the Relationship between Perceived Stress and Body Mass Index in Taiwan Young Adults

Perceived stress is the degree of stress experienced by an individual in the face of a stressor. Studies have shown that stress affects emotions, leads to behavioral changes, and is likely to trigger physical illnesses. According to the World Health Organization (WHO), stress is classified as a health epidemic of the 21st century; in the meantime, the percentage of adults being overweight and with obesity has continued to grow after reaching 38.9% in 2016. Hence, it is unclear whether perceived stress has become a factor affecting progressive obesity and whether food addiction (FA) is an intermediate factor. The purposes of this study were to (1) investigate the FA prevalence among young adults in Taiwan, (2) understand correlations among perceived stress, FA, and the body mass index (BMI), and (3) determine the potential mediating effect of FA due to perceived stress on BMI. The study was conducted through an online questionnaire, composed of a basic data form, the Perceived Stress Scale (PSS), and the Yale Food Addiction Scale (YFAS). We received 1994 responses and analyzed 1780 valid samples. Results showed that 231 participants met the FA criteria, accounting for 12.98%. Perceived stress was positively correlated with BMI (95% confidence interval (CI) 0.013~0.088, p-value 7.8 × 10⁻³), and perceived stress was positively associated to FA (95% CI 1.099~1.154, p-value < 10⁻⁴), which was also positively correlated with BMI (95% CI 0.705~2.176, p-value 10⁻⁴). FA significantly mediated the relationship between PSS and BMI with an indirect effect size of 25.18% and 25.48% in the group that scored 31~40 on the PSS. The study concluded that among people seeking weight loss, proper stress management and screening for FA in order to apply related therapies may be an effective method for weight management.

A genetic profile of oxytocin receptor improves moral acceptability of outcome-maximizing harm in male insurance brokers

In recent years, conflicting findings have been reported in the scientific literature about the influence of dopaminergic, serotonergic and oxytocinergic gene variants on moral behavior. Here, we utilized a moral judgment paradigm to test the potential effects on moral choices of three polymorphisms of the Oxytocin receptor (OXTR): rs53576, rs2268498 and rs1042770. We analyzed the influence of each single polymorphism and of genetic profiles obtained by different combinations of their genotypes in a sample of male insurance brokers (n = 129), as compared to control males (n = 109). Insurance brokers resulted significantly more oriented to maximize outcomes than control males, thus they expressed more than controls the utilitarian attitude phenotype. When analyzed individually, none of the selected variants influenced the responses to moral dilemmas. In contrast, a composite genetic profile that potentially increases OXTR activity was associated with higher moral acceptability in brokers. We hypothesize that this genetic profile promotes outcome-maximizing behavior in brokers by focusing their attention on what represents a greater good, that is, saving the highest number of people, even though at the cost of sacrificing one individual. Our data suggest that investigations in a sample that most expresses the phenotype of interest, combined with the analysis of composite genetic profiles rather than individual variants, represent a promising strategy to find out weak genetic influences on complex phenotypes, such as moral behavior.

[The combined effect of genetic factors and attention deficit hyperactivity disorder on the development of dependence on synthetic cannabinoids]

AIM

To develop a model of assessment of individual risk of dependence on synthetic cannabinoids based on genetic factors and diagnosis of attention deficit hyperactivity disorder (ADHD).

MATERIAL AND METHODS

The study included 146 male adolescents using synthetic cannabinoids and 136 healthy people. The genetic study considered the combination of dependence on synthetic cannabinoids and ADHD. Six polymorphisms in the genes of dopaminergic and serotonergic systems were genotyped.

RESULTS AND CONCLUSION

In general, the results of this work confirm the important role of the dopaminergic and serotonergic systems in the pathogenesis of substance use disorders, and the significance of changes in the nucleotide sequences of DRD2, SLC6A3, HTR2A genes in the development of dependence on synthetic cannabinoids with ADHD.

Food addiction in young adult residents of Russia: Associations with emotional and anthropometric characteristics

The incidence of food addiction (FA) and associations between FA and anthropometric and psycho-emotional characteristics of young Russian adults were studied. In this study, 1,237 students (age, M = 20.6, SD = 4.6 years; 79% females) of universities located in four cities of Russia were attended. They provided demographics and filled in the Yale Food Addiction Scale (YFAS), the Dutch Eating Behavior Questionnaire, and the Zung Self-Rating Depression Scale. Data were analysed via Chi-squared tests, logistic regression analysis, and an analysis of covariance. 13.2% of participants met diagnostic criteria for FA based on the YFAS. On average, the participants reported 2.6 FA symptoms (SD = 1.5). FA was more commonly detected in females (OR = 1.86, 95% CI = 1.10, 3.15, p = .021). No relationship was found between age and the incidence of FA. Significant positive associations between FA, the severity of depression (OR = 2.31, 95% CI = 1.91, 2.80, p = .000), and an emotional eating behaviour (OR = 1.45, 95% CI = 1.20, 1.76, p = .000) were found. The waist-to-height ratio was found to be the anthropometric indicator most closely associated with FA (OR = 1.49, 95% CI = 1.27, 1.76, p = .000). HIGHLIGHTS: The prevalence of food addiction in the current sample was 13.2%. In young Russian adults, emotional eating behaviour and depression are associated with food addiction. In young Russian adults, the waist-to-height ratio is the anthropometric indicator most closely associated with food addiction.

Investigating the relationship between reward sensitivity, impulsivity, and food addiction: A systematic review

OBJECTIVE

The aim of the current research was to identify the extent to which reward sensitivity and impulsivity were related to food addiction.

METHOD

Forty-five studies, published from 2009 to June 2019, investigating reward sensitivity and/or impulsivity with food addiction as measured by the Yale Food Addiction Scale were reviewed.

RESULTS

Reward sensitivity, as measured by the Sensitivity to Reward (SR) scale, was positively associated with food addiction in two studies, but failed to yield consistent results in other studies when measured with the Behavioral Inhibition/Behavioral Activation Scales. Self-report impulsivity, as measured by the Barratt Impulsiveness Scale (BIS-11), was consistently associated with food addiction, with attentional impulsivity and motor impulsivity the most consistent subscales. Similarly, food addiction was also consistently associated with Negative Urgency, Positive Urgency, and Lack of Perseverance as measured by the UPPS-P Impulsive Behavior Scale. Food addiction was inconsistently associated with disinhibition, as measured by behavioral tasks, indicating food addiction appears more aligned with self-report measures of impulsivity.

CONCLUSIONS

Research in this field is dominated by university student, overweight and obese samples. Additional research is required to further tease out these relationships.

Twenty Years of the Food Cravings Questionnaires: a Comprehensive Review

Purpose of Review

The Food Cravings Questionnaires (FCQs; Cepeda-Benito, Gleaves, Williams, & Erath, 2000) are among the most widely used instruments for measuring food cravings. In addition to the Food Cravings Questionnaire–Trait (FCQ–T) and the Food Cravings Questionnaire–State (FCQ–S), several modified versions have been developed as well. For their 20th anniversary, this article provides a comprehensive description of the FCQs and reviews studies on their psychometric properties and correlates.

Recent Findings

The FCQs and their modified versions have excellent internal reliability. Expectedly, the FCQ–T (and its derivatives) has higher retest-reliability than the FCQ–S as the FCQ–S is sensitive to situational changes such as food deprivation and food intake. However, while the FCQ–T is largely unaffected by such momentary states, it is also sensitive to change during weight-loss treatments and other interventions. Factor structure of the FCQ–T and FCQ–S has only partially been replicated. Construct validity of the FCQs is supported by experimental and longitudinal studies that measured food craving and food consumption in the laboratory and with ecological momentary assessment.

Summary

Numerous studies support reliability and validity of the FCQs and their modified versions, yet findings about their factor structures are inconsistent. Thus, using total scores or the short versions of the FCQs may be preferable.

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.

Food Addiction in Eating Disorders and Obesity: Analysis of Clusters and Implications for Treatment

Food addiction (FA) has been associated with greater psychopathology in individuals with eating disorders (ED) and obesity (OBE). The current study aims to provide a better phenotypic characterization of the FA construct by conducting a clustering analysis of FA in both conditions (ED and OBE). The total sample was comprised of 234 participants that scored positive on the Yale Food Addiction Scale 2.0. (YFAS-2) (119 bulimia nervosa (BN), 50 binge eating disorder (BED), 49 other specified feeding or eating disorder (OSFED) and 16 OBE). All participants completed a comprehensive battery of questionnaires. Three clusters of FA participants were identified. Cluster 1 (dysfunctional) was characterized by the highest prevalence of OSFED and BN, the highest ED severity and psychopathology, and more dysfunctional personality traits. Cluster 2 (moderate) showed a high prevalence of BN and BED and moderate levels of ED psychopathology. Finally, cluster 3 (adaptive) was characterized by a high prevalence of OBE and BED, low levels of ED psychopathology, and more functional personality traits. In conclusion, this study identified three distinct clusters of ED-OBE patients with FA and provides some insight into a better phenotypic characterization of the FA construct when considering psychopathology, personality and ED pathology. Future studies should address whether these three food addiction categories are indicative of therapy outcome.

Compulsive eating behaviors in Parkinson's disease

PURPOSE

Eating disorders are common in Parkinson's disease (PD) patients and often class in Impulse control disorders, however, little is known about their phenomenology. Specific symptoms and comorbidities were described in a group of PD patients in this preliminary study.

METHODS

Over a period of 6 months, 51 PD patients who experienced significant changes in eating habits following diagnosis of PD and were interviewed during regularly scheduled follow-up visits. We assessed each patient's height and weight, impulsivity, psychological distress, current eating disorder symptoms, food addiction, food habits and craving.

RESULTS

Among the PD patients who experienced modified dietary habits following diagnosis, few exhibited binge eating disorders (BED) full criteria (3.9%). However, 21.6% of patients experienced episodes of out-of-control eating with a large quantity of food in short time and 39.2% satisfied food addiction (FA) criteria without binge eating disorder. Food cravings more than once a week were experienced in approximately half of the population including all FA patients. Regarding comorbidities, FA PD patients present impulsive features and anxiety.

CONCLUSIONS

This study confirms the existence of FA profile in PD patients. Eating disorders even in PD are complex and have a cross-cutting criteria related to out-of-control eating, FA, and BED. The association of anxiety with PD-related food addiction, contrary to L-dopa equivalent daily dose mean score or the presence of dopamine agonists, underline the complex sustainability of the dopaminergic brainstem support. A study on their detailed prevalence in this population could be helpful to better understand unspecified feeding or eating disorder.

CLINICAL TRIAL NUMBER

DR-2012-007.

NAME OF THE REGISTRY

French Committee for the Protection of Persons (CPP) & French National Commission on Computing and Liberty (CNIL).

LEVEL OF EVIDENCE

Level V, descriptive study.

Ethical, Stigma, and Policy Implications of Food Addiction: A Scoping Review

The concept of food addiction has generated much controversy. In comparison to research examining the construct of food addiction and its validity, relatively little research has examined the broader implications of food addiction. The purpose of the current scoping review was to examine the potential ethical, stigma, and health policy implications of food addiction. Major themes were identified in the literature, and extensive overlap was identified between several of the themes. Ethics sub-themes related primarily to individual responsibility and included: (i) personal control, will power, and choice; and (ii) blame and weight bias. Stigma sub-themes included: (i) the impact on self-stigma and stigma from others, (ii) the differential impact of substance use disorder versus behavioral addiction on stigma, and (iii) the additive stigma of addiction plus obesity and/or eating disorder. Policy implications were broadly derived from comparisons to the tobacco industry and focused on addictive foods as opposed to food addiction. This scoping review underscored the need for increased awareness of food addiction and the role of the food industry, empirical research to identify specific hyperpalatable food substances, and policy interventions that are not simply extrapolated from tobacco.

Uncontrolled eating: a unifying heritable trait linked with obesity, overeating, personality and the brain

Many eating-related psychological constructs have been proposed to explain obesity and overeating. However, these constructs, including food addiction, disinhibition, hedonic hunger, emotional eating, binge eating and the like all have similar definitions, emphasizing loss of control over intake. As questionnaires measuring the constructs correlate strongly (r > 0.5) with each other, we propose that these constructs should be reconsidered to be part of a single broad phenotype: uncontrolled eating. Such an approach enables reviewing and meta-analysing evidence obtained with each individual questionnaire. Here, we describe robust associations between uncontrolled eating, body mass index (BMI), food intake, personality traits and brain systems. Reviewing cross-sectional and longitudinal data, we show that uncontrolled eating is phenotypically and genetically intertwined with BMI and food intake. We also review evidence on how three psychological constructs are linked with uncontrolled eating: lower cognitive control, higher negative affect and a curvilinear association with reward sensitivity. Uncontrolled eating mediates all three constructs' associations with BMI and food intake. Finally, we review and meta-analyse brain systems possibly subserving uncontrolled eating: namely, (i) the dopamine mesolimbic circuit associated with reward sensitivity, (ii) frontal cognitive networks sustaining dietary self-control and (iii) the hypothalamus-pituitary-adrenal axis, amygdala and hippocampus supporting stress reactivity. While there are limits to the explanatory and predictive power of the uncontrolled eating phenotype, we conclude that treating different eating-related constructs as a single concept, uncontrolled eating, enables drawing robust conclusions on the relationship between food intake and BMI, psychological variables and brain structure and function.

[Genetics factors in pathogenesis and clinical genetics of binge eating disorder]

Genetic studies have shown that binge eating disorder (ВЕD) aggregates in families, heritability was estimated as about 60% and additive genetic influences on BED up to 50%. Using a genetic approach has proved useful for verifying the diagnostic categories of BED using DSM-IV criteria and supporting the validity of considering this pathology as a separate nosological category. The results confirmed the genetic and pathogenic originality of BED as a separate psychopathological phenomenon, but not a subtype of obesity. It seems fruitful to considerate BED as a disease with hereditary predisposition with significant genetic influence and a complex psychopathological syndrome, including not only eating disorders, but also depressive and addictive component. A possible mechanism of pathogenesis of BED may be the interaction of the neuroendocrine and neurotransmitters systems including the active involvement of the reward system in response to a variety of chronic stress influences with the important modulatory role of specific personality traits. The high level of genetic influence on the certain clinical manifestations of BED confirms the ability to identify the subphenotypes of BED on genetic basis involving clinical criteria. It can not only contribute to further genetic studies, taking into account more homogeneous samples, but also help in finding differentiated therapeutic approaches.

HPA-axis multilocus genetic variation moderates associations between environmental stress and depressive symptoms among adolescents

Research suggests that genetic variants linked to hypothalamic-pituitary-adrenal (HPA)-axis functioning moderate the association between environmental stressors and depression, but examining gene–environment interactions with single polymorphisms limits power. The current study used a multilocus genetic profile score (MGPS) approach to measuring HPA-axis–related genetic variation and examined interactions with acute stress, chronic stress, and childhood adversity (assessed using contextual threat interview methods) with depressive symptoms as outcomes in an adolescent sample (ages 14–17, N = 241; White subsample n = 192). Additive MGPSs were calculated using 10 single nucleotide polymorphisms within HPA-axis genes (CRHR1, NR3C2, NR3C1, FKBP5). Higher MGPS directly correlated with adolescent depressive symptoms. Moreover, MGPS predicted stronger associations between acute and chronic stress and adolescent depressive symptoms and also moderated the effect of interpersonal, but not noninterpersonal, childhood adversity. Gene–environment interactions individually accounted for 5%–8% of depressive symptom variation. All results were retained following multiple test correction and stratification by race. Results suggest that using MGPSs provides substantial power to examine gene–environmental interactions linked to affective outcomes among adolescents.