OBJECTIVE:Specific diagnostic criteria for purging disorder (PD) are not currently provided in the DSM-5. The current study aims to compare point prevalence estimates and evidence of predictive validity for four alternative criteria sets for PD for men and women. METHOD:Survey data collected in college (N = 3291) and at 10-year follow-up (n = 2223) were used in analyses. Point prevalence was assessed at both time points and compared in men versus women as well as in college versus at 10-year follow-up. Predictive validity was assessed using multiple linear regressions to determine prospective associations for each PD definition versus no eating disorder across external validators. RESULTS:Point prevalence was greater in women than in men in college across all definitions of PD, and no sex differences were found at follow-up. Point prevalence was greater in college than at follow-up in all but the narrowest definition of PD which required purging, on average, twice per week. Predictive validity was supported for PD defined by self-induced vomiting, laxative or diuretic misuse, with evidence of lower satisfaction with work and career at follow-up. DISCUSSION:Together, findings support defining PD through self-induced vomiting, laxative use, or diuretic use to influence body shape or weight, on average, at least once per week. Specifying diagnostic criteria for PD that demonstrate evidence of concurrent and predictive validity will contribute to improved diagnostic reliability, screening, assessment, and support future research efforts to improve treatment.

OBJECTIVE:Bulimia nervosa and related syndromes (BN-S) are clinically heterogeneous and complex disorders. Frequent comorbidity with anxiety disorders (ADs) and substance use disorders (SUDs) implicates inherent fear- and approach-based tendencies in BN-S. This study aimed to clarify how comorbid ADs and SUDs, along with fear- and approach-based traits, influence the presentation and severity of BN-S. METHOD:Women (N = 399) with BN-S (n = 321) or no history of eating disorders (n = 78) completed the Eating Disorder Examination, Structured Clinical Interview for DSM-5 Disorders, Behavioural Inhibition System/Behavioural Activation System scales, and the Sensitivity to Punishment and Sensitivity to Reward Questionnaire. RESULTS:Diagnostic features, symptom frequencies, and eating pathology scores were not significantly affected by comorbidity with ADs or SUDs. Controlling for ADs, participants with BN-S scored significantly higher than controls on fear-based traits. Similarly, controlling for SUDs, individuals with BN-S showed elevated sensitivity to reward. Finally, elevated fear- and approach-based traits both contributed to elevated severity across a range of bulimic symptoms. CONCLUSION:Fear- and approach-based traits coexist in individuals with BN-S and were associated with the same symptoms. Although BN-S are currently placed within the Hierarchical Taxonomy of Psychopathology's internalising spectrum, findings indicate overlap with the externalising spectrum.

Societal and cultural shifts can influence psychological well-being and development in adulthood. Maturity fears, an individual's desire to retreat to the security of childhood, have been found to be increasing in younger generations. The present study explored how maturity fears change over adult development in three cohorts of university students assessed in 1982, 1992, and 2002 and followed over time. The study employed a sequential design in which university students (N = 2,482, 69.8% female) completed self-report surveys in college and at 10-year and 20-year follow-up. At baseline, female in the 2002 cohort showed the highest maturity fears, followed by 1992 and then 1982, with all cohorts having decreases in maturity fears over time. There was a significant Cohort × Time interaction, such that compared to the 1982 cohort, both the 1992 and 2002 cohorts demonstrated significantly greater declines in maturity fears over time. Males in the 1992 and 2002 cohorts showed greater maturity fears than those in the 1982 cohort. As with the females, for males there was a significant Cohort × Time interaction. Compared to the 1982 cohort, both the 1992 and 2002 cohorts demonstrated significantly greater declines in maturity fears over time. Overall, the pattern of findings indicates higher levels of maturity fears during college in more recent cohorts, a decrease in maturity fears during adult development, and greater declines in more recent generations. Additional research is needed to not only replicate these findings but also explore potential mechanisms underlying cohort differences. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

The Eating Disorder Inventory (EDI) is one of the oldest and most widely used surveys of eating disorder thoughts and behaviors. Its recent and frequent use to study differences in eating pathology across ethnoracial groups underscores importance of establishing its measurement invariance across groups. However, mixed evidence has emerged, and studies have focused on Black, mixed-race Hispanic/Latino, and White women. The present study aimed to establish the measurement invariance of the EDI Drive for Thinness, Bulimia, Perfectionism, Maturity Fears, and Interpersonal Distrust subscales across four ethnoracial groups in a sample of women and men. Participants (N = 2,931) were Hispanic White (7%), non-Hispanic Asian (18%), non-Hispanic Black or African American (7%), and non-Hispanic White (68%) college students (67% female) recruited in a cohort-based epidemiological, longitudinal study of health and eating patterns. First, multigroup confirmatory factor analysis examined whether the EDI performed comparably across ethnoracial groups in the full sample. Next, the same approach was followed in sensitivity analyses within each sex. Evaluation of changes in comparative fit index indicated that full metric invariance, scalar invariance, and uniqueness were supported across ethnoracial groups in the full sample and in women (change in comparative fit index ≤ .01). Only partial measurement invariance was supported in analyses of non-Hispanic Asian and non-Hispanic White men. Analyses support use of the EDI in ethnoracially diverse samples including women and men or only women. Limited score variance in men suggests the need for tests of measurement invariance in larger samples. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Importance:Previous studies suggest endogenous ovarian hormones significantly increase binge-eating (BE) risk in females. Approximately 85% of women use combined oral contraceptives (COCs) that mimic the riskiest hormonal milieu for BE (ie, elevated estradiol and progesterone postovulation). The effects of COCs on BE risk remain unknown. Objective:To examine the associations of COCs with BE. Design, Setting, and Participants:This population-based longitudinal survey study collected daily reports of COC active vs inactive pill use and BE across 49 consecutive days in women from the Michigan State University Twin Registry. Analyses examined within-person changes in a continuous measure of BE (ie, emotional eating [EE]) when women were using active hormone pills vs inactive pills. Data were collected from 2017 to 2024. Participants were women already using monophasic COCs. Analyses examined the full sample as well as women with clinically defined BE episodes. Data were analyzed from April 2024 to November 2025. Exposure:COC pill type (active vs inactive pills). Main Outcomes and Measures:The outcome of interest was within-person changes in EE between inactive vs active hormone pills, controlling for negative affect. Changes across 2 pill packs were examined for replication. Analyses also examined weight preoccupation (WP) as a control outcome, given its lack of past associations with ovarian hormones. Primary models focused on the full sample; sensitivity analyses examined women with clinically defined BE. Results:A total of 422 women (mean [SD] age, 21.95 [3.10] years) were included in the full sample. Significant within-person increases in EE were observed in the full sample during active hormone vs inactive pills in both cycles (cycle 1: β = 0.11 [95% CI, 0.06 to 0.16]; cycle 2: β = 0.07 [95% CI, 0.04 to 0.10]). Increases were not mediated by changes in negative affect and were observed in the subsample of 51 women (mean [SD] age, 22.44 [3.57] years) with clinically defined BE episodes (cycle 1: β = 0.13 [95% CI, -0.07 to 0.33]; cycle 2: β = 0.12 [95% CI, 0.02 to 0.23]. Importantly, no significant changes in WP were observed across pill type, and post hoc analyses of negative affect as the outcome showed more modest COC outcomes. Conclusions and Relevance:This intensive, daily survey study of COC use found a specific association of active COC pills with risk for EE. Future studies are needed to identify for whom COCs are most risky to inform personalized medicine and identify contraceptive options that may be less likely to impact BE or EE.

OBJECTIVE:This narrative review provides an accessible overview of purging disorder for clinicians, researchers, policymakers, and the public, emphasizing the importance of accurate communication and early detection for effective intervention. METHOD:Key findings are synthesized on diagnostic characteristics, prevalence, risk factors, cultural and gender considerations, comorbidity, functional impairment, and treatment needs. RESULTS:Although currently embedded in the DSM-5 "Other Specified Feeding and Eating Disorders" (OSFED) category, research demonstrates that purging disorder has distinct clinical features, medical risks, and developmental pathways. DISCUSSION:This narrative review highlights ongoing debates regarding classification and outlines public-health priorities for improving detection, research, and care.

Limited prospective research examines how ethnicity and race impact changes in eating pathology over time. To date, most research has focused on the adolescent developmental period and has not accounted for body mass index (BMI), an established risk factor for eating pathology that differs by ethnicity and race. The current study aimed to close this gap by examining ethnoracial status and its intersection with gender as a predictor of levels and changes in BMI, Eating Disorder Inventory (EDI) bulimia scores, and EDI drive for thinness (DT) scores over a 20-year period from early to middle adulthood. Two cohorts of university students established in 1982 and 1992 provided survey responses at baseline (n = 1,415; 71% female) and were sought for 10- and 20-year follow-up. Multilevel models indicated Hispanic White and non-Hispanic Black/African American ethnoracial groups demonstrated greater increases in BMI over time compared to non-Hispanic Asian and non-Hispanic White ethnoracial groups. EDI bulimia and DT scores were comparable across ethnoracial groups in college. Trajectories for DT were also comparable across ethnoracial groups. Conversely, ethnoracial status was a predictor of differing trajectories of EDI bulimia among women, such that non-Hispanic Black/African American women's bulimia scores demonstrated significantly less decline over time compared to non-Hispanic Asian and non-Hispanic White women's scores. While eating pathology is stereotypically linked to young, White women, results suggest sustained propensity for binge eating among Black/African American women into midlife. Future research should examine factors such as exposure to weight stigma and internalized weight bias that may contribute to this effect. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Objective We sought to examine (1) the effects of ethnoracial status on Drive for Thinness (DT) and bulimic symptoms in a large sample of women, and (2) whether the strength of the association between DT and bulimic symptoms differed among ethnoracial groups. Method Participants (M age = 19.59 years) from five ethnoracial groups (n = 14 American-Indian/Alaska Native, n = 233 Asian, n = 186 Black, n = 125 Hispanic White, and n = 990 non-Hispanic White), completed Eating Disorder Inventory (EDI; Garner et al., 1983) scales. Results EDI DT scores were significantly lower in Black women compared to both Hispanic and non-Hispanic White women. EDI Bulimia scores were significantly lower in Black women compared to Asian, Hispanic, and non-Hispanic White women. No significant differences were observed among Asian, Hispanic, or non-Hispanic White women. Ethnoracial status moderated the association between DT and Bulimia scores, with a significantly weaker association in Black women compared to Asian, Hispanic, and non-Hispanic White women. Discussion Findings refute misconceptions that disordered eating uniquely impacts White women and support a nuanced understanding of how ethnoracial status may influence eating disorder risk. Future work should examine sociocultural factors unique to ethnoracial subgroups to inform more targeted and effective intervention strategies.

OBJECTIVE:Suicidal ideation represents a serious experience common in individuals with eating disorders. To inform screening and clinical assessment and advance theoretical work, the current study compared clinical characteristics between adult women with and without current suicidal ideation and examined whether binging, fasting, and purging behaviors are uniquely associated with suicidal ideation above and beyond existing psychiatric diagnoses. METHOD:Data come from four studies conducted between 2000 and 2023 (N = 732) that evaluated current suicidal ideation in all participants. Participants completed diagnostic interviews assessing lifetime psychiatric diagnoses and current eating disorder diagnoses and behavioral symptom frequencies. Five hundred and fifty-three participants had DSM-5 eating disorders (54.6% bulimia nervosa, 15.0% purging disorder [PD], 28.2% other specified [excluding PD], 1.4% anorexia nervosa, and 0.7% binge-eating disorder). RESULTS:Individuals with current suicidal ideation had a greater prevalence of most psychiatric diagnoses and greater frequency of binging, fasting, and purging. Additionally, purging frequency was associated with current suicidal ideation independent of binging, fasting, and lifetime psychiatric comorbidities. DISCUSSION:Results support prior work suggesting that purging may fall on the self-harm continuum with nonsuicidal self-injury. Further, findings support screening for purging and suicide risk assessment in individuals with eating disorders.

BackgroundBulimia nervosa and related syndromes (BN-S) characterized by binge eating vary considerably in illness severity and course. Using the Research Domain Criteria framework of the National Institute of Mental Health, we developed a model positing that the same set of physiological consequences of weight suppression (WS; defined as the difference between the highest and current adult body weight) contribute to binge-eating severity and maintenance by (1) increasing the drive or motivation to consume food (reward valuation effort [RVE]) and (2) decreasing the ability for food consumption to lead to a state of satiation or satisfaction (reward satiation). ObjectiveOur funded project aimed to test concurrent associations among WS, physiological factors (leptin concentrations and postprandial glucagon-like peptide 1 [GLP-1] response), behavioral indicators of RVE (breakpoint on progressive ratio tasks) and reward satiation (ad-lib test meal intake), self-report of these core constructs, and binge-eating severity in BN-S (aim 1); test prospective associations to determine whether WS predicts BN-S maintenance in longitudinal models and whether posited mediators also predict BN-S maintenance (aim 2); and determine whether associations between WS and BN-S severity and maintenance are mediated by alterations in leptin levels, GLP-1 response, RVE, and reward satiation (aim 3). MethodsWe aimed to recruit a sample of 320 women with BN-S or noneating disorder controls, with BMI from 16 kg/m2 to 35 kg/m2, for our study. The study included diagnostic interviews; questionnaires; height, weight, and percentage of body fat measurements; weight history; fasting leptin level; postprandial GLP-1 and insulin responses to a fixed meal; and ad-lib meal and progressive ratio tasks to behaviorally measure reward satiation and RVE, respectively, at baseline, with at least 78.1% (250/320) of the participants providing data at 6- and 12-month follow-up visits. Data will be analyzed using structural equation models to test posited pathways. ResultsData collection began in November 2016 and ended in April 2023, pausing in-person data collection from March 2020 to February 2021 due to the COVID-19 pandemic. Of 399 eligible women enrolled, 290 (72.7%) provided clinical, behavioral, and biological data at baseline, and 249 (62.4%) provided follow-up data. Measures demonstrated strong psychometric properties. ConclusionsWe seek to identify biobehavioral predictors to inform treatments that target key factors influencing the severity and course of binge eating. These data, supported solely through federal funding, can inform questions emerging from recent interest and controversy surrounding the use of GLP-1 agonists for binge eating. International Registered Report Identifier (IRRID)RR1-10.2196/66554

OBJECTIVE:Extensive research has documented the impact of social media use on risk for eating disorders. The present study used a longitudinal design to test the hypotheses that greater disordered eating prospectively predicts increased engagement with content promoting restrictive eating on TikTok. After data collection began, the university initiated a TikTok ban, adding a quasi-experimental design to explore the impact of the ban on engagement with restrictive eating content. METHODS:Female college students (N = 252) between the ages of 18 and 24 years (M = 19.60, SD = 1.26) completed measures of eating pathology and TikTok engagement with restrictive eating content at baseline and at 9-week follow-up. RESULTS:Higher disordered eating at baseline prospectively predicted greater engagement with restrictive eating content on TikTok at follow-up, but social media engagement did not predict disordered eating. The university ban on TikTok had no impact on engagement with restrictive eating content. Engagement with restrictive eating content and disordered eating increased over time. DISCUSSION:Individuals with eating pathology may be drawn to portrayals of restrictive diets by creators with idealized body types, prompting algorithms to push this content and creating a harmful cycle between exposure and risk. Interventions embedded within social media may prove more effective in reducing risk for eating disorders than institutional bans attempting to limit social media access.

BACKGROUND:Formation of Diagnostic and Statistical Manual of Mental Disorders (DSM) subcommittees combined with recently approved coding designations for bulimia nervosa (BN) in partial remission highlights the need to examine the validity of the threshold that distinguishes BN from other specified feeding or eating disorders (OSFED) BN of low frequency and/or limited duration (OSFED-BN). METHODS:Women (N = 344) who met DSM-5 criteria for BN (n = 153) or OSFED-BN (n = 118) or had no lifetime eating disorder symptoms (n = 78) completed assessments of height, weight, weight history, percent body fat, structured clinical interviews for DSM-5 disorders, suicidality, trauma, and treatment histories, and self-report questionnaires covering a range of validators related to eating disorders, psychological traits, and general psychopathology. Comparisons across groups tested the validity of OSFED-BN and whether prior history of DSM-5 BN impacted evidence of its clinical significance and distinctiveness. RESULTS:Lower frequency of binge eating was the primary reason for diagnosis of OSFED-BN vs. BN; more than 80% of those with OSFED-BN met or exceeded frequency and duration criteria for inappropriate compensatory behaviors. The current DSM-5 threshold distinguishing BN from its OSFED variant or from BN in partial remission produced few differences relative to several large differences observed for comparisons of these diagnostic groups and non-eating disorder controls. DISCUSSION:Despite being associated with distinct DSM-5 diagnostic codes, BN, BN in partial remission, and OSFED-BN appear to represent a single condition that may, at most, capture some dimensional differences in severity. Findings support lowering the current minimum frequency thresholds for diagnosing BN.

INTRODUCTION:Ovarian hormones (i.e., estradiol, progesterone) show robust phenotypic associations with binge eating and related behaviors (e.g., emotional eating) in females. Recent research suggests these associations may be due to ovarian hormone effects on genetic and environmental influences on dysregulated eating. However, no research has yet examined how within-person fluctuations in hormone levels impact genetic/environmental influences on day-to-day changes in dysregulated eating from an individual's own mean. This omission is critical because phenotypic associations between ovarian hormones and dysregulated eating are strongest at a within-person level in adult women, suggesting potentially unique and important within-person effects. METHOD:Participants from same-sex female twin pairs (N = 468) from the MSU Twin Registry provided measures of ovarian hormones and emotional eating daily for 49 consecutive days. We used continuous twin moderation models to examine how within-person centered estradiol and progesterone impacted genetic/environmental influences on within-person shifts in emotional eating. RESULTS:Within-person fluctuations in estradiol and progesterone significantly moderated genetic influences on within-person changes in emotional eating. Stronger genetic influences were observed when the ratio of within-person estradiol to progesterone was in the moderate range. CONCLUSION:Cyclic, within-person changes in ovarian hormones may contribute to phenotypic changes in dysregulated eating across the menstrual cycle by dynamically regulating expression of underlying genetic risk. Genetic influences may be particularly pronounced under the hormonal conditions characteristic of the mid-luteal phase (i.e., moderate estradiol and progesterone).

OBJECTIVE:Prior efforts to define maladaptive exercise indicate that compensatory and compulsive features and exercising for appearance are associated with disordered eating in cross-sectional studies. However, the predictive validity of these definitions in adults requires examination. This study employs a 10-year longitudinal cohort design to evaluate whether these established definitions of maladaptive exercise predict disordered eating and weight-related outcomes. METHODS:Men (n = 592) and women (n = 1467) completed surveys of exercise and disordered eating in 2002, and 74% completed surveys at the 10-year follow-up. Exercise amount (duration and frequency), compensatory, appearance, and compulsive exercise were tested as prospective predictors of body mass index (BMI), Drive for Thinness, and Bulimia. RESULTS:Exercise for appearance prospectively predicted higher BMI, Drive for Thinness, and Bulimia at follow-up. Compensatory exercise also uniquely predicted higher BMI at follow-up, and compulsive exercise demonstrated no unique prospective associations with disordered eating or weight-related outcomes. DISCUSSION:The unique effect of appearance exercise highlights the importance of addressing exercise motivations to reduce disordered eating risk. Such work may highlight that exercising for weight control or body definition predicts higher BMI and more disordered eating over the long term. Future studies should employ longitudinal designs, with multiple waves of follow-up, to examine potential bidirectional influences between maladaptive exercise and disordered eating as well as the long-term health consequences of maladaptive exercise.

BACKGROUND:Weight suppression represents the difference between highest and current body weight and predicts maintenance of bulimia nervosa and related syndromes (BN-S). This study tested a biobehavioral model of binge-eating severity in which greater weight suppression links to reduced leptin, which links to reduced glucagon-like peptide 1 (GLP-1) release, which links to both decreased reward satiation and increased reward valuation, which link, respectively, to excessive food intake and loss of control while eating - the defining features of DSM-5 binge-eating episodes. METHODS:Women (N = 399) who met DSM-5 criteria for bulimia nervosa or another eating disorder with binge eating (n = 321) or had no lifetime eating disorder symptoms (n = 78) participated in a multi-visit protocol, including structured clinical interviews, height, weight, weight history, percent body fat, fasting leptin, post-prandial GLP-1 response to a fixed meal, and self-report and behavioral assessments of food reward satiation (ad lib meal) and food and nonfood reward valuation (progressive ratio tasks). RESULTS:A structural equation model (SEM) demonstrated excellent fit to data with significant pathways from greater weight suppression to lower leptin, to blunted GLP-1 response, to lower reward satiation, to larger eating/binge-eating episode size, with significant indirect paths through leptin, GLP-1, and reward satiation. SEM with paths via reward valuation to loss of control eating demonstrated inadequate fit. CONCLUSIONS:Findings specifically link reduced GLP-1 response to severity of binge-episode size and support weight history assessment in eating disorders, DSM-5 over ICD-11 criteria for binge eating, and may inform future clinical trials of GLP-1 agonists for BN-S.

OBJECTIVE:The Muscularity-Oriented Eating Test (MOET) was developed to measure muscularity-oriented eating pathology among young men; however, this construct is relevant across sexes and may be particularly applicable to athletes. Thus, this study sought to validate the MOET among male and female athletes and non-athletes. METHODS:Students (N = 2189) from three U.S. universities completed an online survey. Confirmatory factor analyses (CFA) testing two MOET versions (12-items, 15-items) were conducted in male and female athletes and non-athletes. Chi-squared tests and invariance analyses were used to evaluate the fit of each model across groups. Convergent validity of the MOET was assessed with Spearman correlation tests. RESULTS:A one-factor CFA displayed adequate fit for 12-item and 15-item versions across all groups, except the 15-item version in the full sample. Chi-squared tests indicated superior fit of 12-item MOET CFAs among male and female athletes, female non-athletes, and all participants compared to 15-item models (adjusted p < .050); no difference in fit was evidenced between 12-item and 15-item CFAs for male non-athletes (adjusted p = .062). Both versions showed similar convergent validity. CONCLUSIONS:A 12-item MOET may provide improved screening for muscularity-oriented eating pathology in male and female athletes and female non-athletes.

OBJECTIVE:The transformation framework conceptualizes social media as reshaping traditional peer influences and could enhance understanding of disordered eating. This cross-sectional study examined (1) independent associations of friend dieting and social media exposure with eating pathology, (2) whether social media exposure moderates the relationship between friend dieting and eating pathology, and (3) explored whether sex and age moderate independent and combined effects of friend dieting and social media exposure on eating pathology. METHOD:A large sample of men and women (N = 1860) ranging in age from 28 to 69 years (M = 47.24 years, SD = 10.71), completed surveys assessing friends' behaviors, social media exposure, and eating pathology. RESULTS:Friend dieting and social media exposure showed independent associations with bulimic symptoms and drive for thinness. Greater social media exposure strengthened the relationship between friend dieting and bulimic symptoms in younger men and older women, and between friend dieting and drive for thinness in younger men and men at the mean age. DISCUSSION:Findings partially support hypotheses from the transformation framework, with the most consistent support found for younger men. Future work should examine how social media exposure amplifies the frequency, immediacy, and impact of peer influence on disordered eating to inform social media literacy programs tailored to adults.

BACKGROUND:Trait-level emotion regulation (ER) difficulties are associated with eating disorders (EDs) transdiagnostically. However, little research has examined whether within-person fluctuations in ER longitudinally predict ED behaviors in daily life or the mechanisms of ER effects. Investigating daily ER could help us better understand why people experience ED behaviors at a given time. We examined whether day-to-day changes in adaptive (e.g., cognitive reappraisal) and maladaptive (e.g., rumination) ER longitudinally predicted core ED behaviors (binge eating, purging, dieting) and whether changes in affect mediated effects. METHOD:Female participants (N = 688) ages 15-30 from the Michigan State University Twin Registry reported their adaptive and maladaptive ER use, negative affect (NA), positive affect (PA), binge eating, purging, and dieting on 49 consecutive days. Using structural equation modeling, we examined whether within-person fluctuations in ER predicted same- and next-day ED behaviors and whether changes in affect mediated longitudinal ER effects. RESULTS:Greater maladaptive ER predicted increased likelihood of same-day binge eating and next-day binge eating and purging. The association between maladaptive ER and next-day binge eating and purging was mediated by increased next-day NA. In contrast, dieting was more closely related to changes in PA. Adaptive ER did not predict reduced likelihood of any ED behavior. CONCLUSIONS:Maladaptive ER may longitudinally increase risk for binge eating and purging by amplifying NA. Interventions focused on decreasing maladaptive ER and subsequent NA might help disrupt binge eating-purging cycles. Conversely, results add to evidence that PA fluctuations may play a unique role in maintaining restrictive behaviors. PUBLIC SIGNIFICANCE:Little is known about how daily changes in emotion regulation may impact disordered eating. We found that maladaptive emotion regulation (e.g., rumination) was associated with a higher likelihood of binge eating and purging on the next day because it predicted increased next-day negative affect. In contrast, dieting was more closely tied to fluctuations in positive affect. Targeting daily emotion regulation and affective processes may help disrupt cycles of disordered eating.

OBJECTIVE:Binge-eating spectrum disorders (BESD) involve large eating episodes accompanied by a sense of loss of control that occur in individuals with body weights spanning the full body mass index (BMI) spectrum. While research links BESD with peripheral inflammation, this literature is limited by underpowered studies and a failure to control for confounding variables that could promote inflammation independent of dysregulated eating, specifically elevated body adiposity and depression. Our study examined plasma interleukin-6 (IL-6), a marker of peripheral inflammation, in a sample of women with BESD and non-eating disorder controls, controlling for BMI, body adiposity, and depression. METHOD:Participants (N = 94) included women with BESD (n = 73) or no eating disorder (n = 21) who completed structured clinical interviews in a larger study, selected to represent BMI categories ranging from underweight to obese in both groups. Fasting blood samples were processed for plasma IL-6 concentration via enzyme-linked immunosorbent assays. In addition to assessing group differences in plasma IL-6, exploratory analyses examined associations between IL-6 and biological and clinical markers of BESD. RESULTS:Significantly elevated plasma IL-6 was found in women with BESD, relative to controls, that was not accounted for by BMI, adiposity, or depression. Plasma IL-6 was positively correlated with plasma leptin concentration, clinical assessments of eating disorder severity, and participants' largest self-reported eating episode. DISCUSSION:Peripheral inflammation is specifically linked to presence of dysregulated eating independently from weight, adiposity, and depression in BESD. Future research should probe the potential role of neuroinflammation in altered eating behavior. PUBLIC SIGNIFICANCE:This study provides the first demonstration that inflammation, characterized by elevated plasma IL-6 concentration, is uniquely associated with dysregulated eating in a transdiagnostic group of individuals with BESD. A better understanding of whether immune factors contribute to dysregulated eating could help identify novel biological targets for intervention.

Reward responses to food are thought to play an important role in highly palatable food overconsumption. In animal models, food reward responses can be decoupled into unique "liking" (in the moment enjoyment) and "wanting" (motivation/craving) components. However, research on liking and wanting has been hampered by uncertainty regarding whether liking and wanting can be reliably separated in humans. We used factor analysis to test whether ratings of liking and wanting could be empirically separated in women assessed across 49 consecutive days. Female participants (N = 688; ages 15-30) from the Michigan State University Twin Registry reported liking and wanting of foods consumed that day, and wanting of foods not consumed that day, separately for sweets (e.g., cookies), fast food (e.g., French fries), carbohydrates (e.g., bread), and whole foods (fruit, plain chicken) each evening for 49 consecutive days. We examined both average levels and daily levels of liking/wanting across the 49-day period that captured individual differences in liking/wanting over time. Across both types of analyses, liking and wanting for foods that were eaten formed a single factor rather than separate, dissociable factors, while wanting of foods not eaten formed an independent factor. At the daily level, a liking/wanting factor emerged for each individual food category (e.g., liking/wanting sweets), whereas in average analyses, a single factor emerged that collapsed across all food types (i.e., liking/wanting of all foods). Results suggest individuals have difficulty distinguishing between liking and wanting of foods they have eaten on that day but may be able to more reliably separate wanting of foods they have not consumed.