Clinical aspects of binge eating disorder: A cross-sectional mixed-methods study of binge eating disorder experts' perspectives

Introduction Research on binge eating disorder continues to evolve and advance our understanding of recurrent binge eating. Methods This mixed-methods, cross-sectional survey aimed to collect information from experts in the field about clinical aspects of adult binge eating disorder pathology. Fourteen experts in binge eating disorder research and clinical care were identified based on receipt of relevant federal funding, PubMed-indexed publications, active practice in the field, leadership in relevant societies, and/or clinical and popular press distinction. Anonymously recorded semi-structured interviews were analyzed by ≥2 investigators using reflexive thematic analysis and quantification. Results Identified themes included: (1) obesity (100%); (2) intentional/voluntary or unintentional/involuntary food/eating restriction (100%); (3) negative affect, emotional dysregulation, and negative urgency (100%); (4) diagnostic heterogeneity and validity (71%); (5) paradigm shifts in understanding binge eating disorder (29%); and (6) research gaps/future directives (29%). Discussion Overall, experts call for a better understanding of the relationship between binge eating disorder and obesity, including a need for clarification around the extent to which the two health issues are separate vs. related/overlapping. Experts also commonly endorse food/eating restriction and emotion dysregulation as important components of binge eating disorder pathology, which aligns with two common models of binge eating disorder conceptualization (e.g., dietary restraint theory and emotion/affect regulation theory). A few experts spontaneously identified several paradigm shifts in our understanding of who can have an eating disorder (beyond the anorexi-centric “thin, White, affluent, cis-gendered neurotypical female” stereotype), and the various factors that can drive binge eating. Experts also identified several areas where classification issues may warrant future research. Overall, these results highlight the continual advancement of the field to better understand adult binge eating disorder as an autonomous eating disorder diagnosis.


Introduction
Binge eating disorder (discrete rapid consumption of objectively large amounts of food associated with loss of control and distress without compensatory behaviors) became a formally recognized autonomous eating disorder diagnosis with the publication of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-V) in 2013 (1). It was previously classified in the DSM-IV as eating disorder not otherwise specified (ED-NOS) (2). While research and literature on binge eating disorder have been growing, historically there has been greater understanding and awareness of anorexia nervosa and bulimia nervosa, and less so of binge eating disorder. However, the literature continues to evolve and advance our understanding of recurrent binge eating.
Historically, there is a tendency to view binge eating disorder as resulting from overevaluation of body weight/shape/size leading to food/eating restriction and subsequent binge eating (e.g., transdiagnostic-, dietary restraint-, and dual pathway models) (3)(4)(5)(6)(7). However, several alternative conceptualizations of binge eating disorder have gained attention in recent years (4).
Emotion/affect regulation models are perhaps the most widely supported and accepted in the field, along with dietary restraint models (4). These models center around the view that negative emotions, moods, or affective experiences can prompt binge eating, which can become negatively reinforced by providing temporary relief from the associated discomfort (4). In this way, it is believed binge eating can become a maladaptive emotion regulation/coping strategy resulting from lack of more adaptative tools. In these models, the aversive experiences that drive binge eating often include distress (unhappiness, pain, and/or suffering affecting the mind or body) and negative affect (the subjective experience of a cluster of negative emotional states that include anxiety, depression, stress, sadness, worry, guilt, shame, anger, and envy), which can result in negative urgency (an impulsive inclination to engage in risky or unhealthy behaviors when in a state of poor emotion regulation) (8)(9)(10)(11)(12). These models are strongly supported in the literature (4,(8)(9)(10) and-along with dietary restraint-represent commonly overlapping concepts across various conceptualizations of binge eating disorder (e.g., dual pathway models, escape/disassociation models, ICAT models, interpersonal models, and transdiagnostic models) (4).
The issue of obesity also remains a point of contention in the field. Literature demonstrates binge eating disorder has a 40-70% incidence of lifetime obesity (13)(14)(15) and obesity has a ≤47% prevalence of binge eating disorder (16). However, there remains a need for updated information on the extent to which binge eating disorder and weight issues are separate/related/overlapping.
Negative health implications associated with obesity (e.g., cardiometabolic syndrome) highlight another important question of the extent to which binge eating disorder should be considered a purely mental health disorder vs. a physiological/biological one. Weight regulation models of eating disorders are under development that propose weight and weight history are causal variables that have clinically significant impacts on eating disorder psychopathology and perpetuation (17). However, these models remain to be tested.
Here, we present findings from a mixed-methods, cross-sectional survey aimed to collect information from experts in the field about clinical aspects of adult binge eating disorder pathology.

I. Eligibility criteria for researchers ( recruited, enrolled)
Eligibility criteria for researchers required meeting one of the following four criteria: 1. ≥1 active R01, T32, or P grant on binge eating or food addiction as identified on NIH RePORTER (https://report.nih.gov)

II. Eligibility criteria for clinicians and healthcare administrators ( recruited, enrolled)
Eligibility for clinicians and healthcare administrators required meeting ≥3 of the following criteria: 3. Adult binge eating disorder provider listed in the National Eating Disorder Association (NEDA)-or Alliance for Eating Disorders Awareness Provider Directories (33,34) or associated with an eating disorder program or treatment center with ≥5 locations listed in the NEDA directory (33) 4. Popular press distinction (35,36) 5. Referral from an individual meeting ≥2 qualifications above 6. Registered Dietician (RD) meeting ≥2 criteria above

III. Additional Eligibility Criteria ( recruited, enrolled b )
Individuals who met ≥1 academic/research criterion (I) and ≥1 clinical criterion (II) were also eligible. a This criterion required ≥5 publications in the past 5 years because of the relative newness of the concept of food addiction. b Both participants each met two academic/research criteria and two clinician/healthcare administrator criteria.

Participants and recruitment
This study recruited expert researchers, clinicians, and healthcare administrators in the field of adult binge eating disorder. Eligibility criteria is previously published in Bray et al. (18,19) and is shown in Table 1.

Procedure
The procedure is described in Bray et al. (18,19). With approval from the National University of Natural Medicine (NUNM) IRB (# HZ12120), BB sent eligible participants a scripted email study invitation. Consenting respondents were interviewed anonymously Bray et al. .
/fpsyt. .  4. Are there any other aspects of binge eating disorder pathology that you feel are important to address or discuss (that have not been addressed above)?
12 (86%) 5. Please describe your perspective on current research gaps that exist in the field of binge eating disorder. 14 (100%) Results expressed as n (%). n, number participants asked. Percentages expressed as n/14 times 100.
on Zoom (Zoom.com, last accessed May 19, 2022), with verbal consent obtained at the start of each interview. Interviews were recorded with participant consent. Recordings began after introductions, to protect participant anonymity. Most interviews were scheduled for 2 h, with abbreviated 30-60-min interviews conducted as needed. Interview questions pertaining to binge eating disorder pathology are shown in Table 2. Demographic information was collected at the end of each interview verbally or through followup email survey.

Data analysis
Interview recordings were transcribed. Transcripts were deidentified and then reviewed and qualitatively analyzed by BB and HZ (separately) for common themes using a reflexive thematic analysis approach (37). BB and HZ independently coded each interview. Themes were identified independently then discussed and finalized through reflexive engagement with the data (37). BB also analyzed transcripts quantitatively to identify the number of participants who expressed positive/supportive, negative/skeptical, or neutral perspectives on each identified theme. HZ and CB were consulted when quantitative analysis questions arose and for tiebreakers.

Participant response rates and characteristics
Thirty-eight experts met enrollment criteria and fourteen consented, enrolled, and participated in the study (Figure 1). Fourteen experts consented, enrolled, and participated in the study, including six individuals who met the academic/research criteria (6/14, 43%), five who met the clinical criteria (5/14, 36%), one who met both the academic/research and clinical criteria (1/14, 7%), and two who met some criteria from the academic-and clinical categories to qualify for inclusion in a mixed option (2/14, 14%) ( Table 1). Table 3 shows characteristics for the 13/14 participants who provided demographic information.

Subtheme i: Relationship between obesity and binge eating disorder ( %)
Thirteen participants made statements expressing views on the nature of the relationship between obesity and binge eating disorder pathology, including the possible directionality or statistical nature of the relationship (11/14, 79%). Eight participants endorsed a common link between obesity and binge eating disorder (8/14, 57%). Five participants (5/14, 36%) described obesity as a condition that many with binge eating disorder struggle with. Four participants (4/14, 29%) noted that not everyone with binge eating disorder has a larger body or obesity. Four participants endorsed a need for clarification on the extent to which obesity and binge eating disorder are separate vs. related/overlapping (4/14, 29%). Three participants expressed views that obesity can motivate treatment for binge eating (3/14, 21%). Two participants described obesity as a negative consequence of binge eating disorder (2/14, 14%). Additional possible relationships that were addressed by only one participant each are included in Supplementary material S1.1. "Many, many people with binge eating disorder have overweight or obesity." (P5) "We interview people with obesity who say, I don't have binge eating, and then a lot of times they will self-report it." (P72) "We've struggled for a long time in the field with the extent to which binge eating disorder and obesity are separate or related, and like a lot of things in the mental health world, I think it's probably not so much an either-or place [but rather a] both-and place." (P5) "[Obesity is] definitely relevant [to binge eating disorder]. . . . It's one of those things that I think everybody thinks that obesity and binge eating disorder have . . . a one-to-one [relationship]. . . [that] 'everybody who is obese has binge eating disorder, '. . . which we know isn't true but certainly, obesity is. . . one of the most likely negative outcomes affiliated and associated with binge eating disorder and . . . I think one of the things that most motivates people to want to come in [for treatment] because our society is really awful to people who have obesity and there's so much stigma that. . . both for the health consequences but also for the desire to have a different body shape is often what can get people in the door [for treatment]." (P19) "People who self-identify as having binge eating disorder are -in my mind -a distinct subgroup from people with obesity in that they experienced that sense of loss, loss of control, they're often more distressed about their eating FIGURE Diagram of study flow, from participant identification to enrollment and follow-up. Thirty-eight experts met enrollment criteria and were invited to participate in the study. This included experts who met the academic/research criteria ( / , %), experts who met the clinical criteria ( / , %), and two who met the dual criteria ( / , %; Table ). Fourteen eligible experts consented, enrolled, and participated in the study ( / , %), including six individuals who met the academic/research criteria ( / , %), five who met the clinical criteria ( / , %), one who met both the academic/research and clinical criteria ( / , %), and two who met the dual criteria option ( / , %) (Table ). Thirteen participants ( / , %) provided demographic information and were included in demographic analysis (Table ). All participant interviews were included in thematic analysis. Reproduced with permission from Bray et. al., ( ).
. /fpsyt. .  Additional participant statements related to subtheme i, "relationship between obesity and BED" "Well clearly lots of research has been done on relationships of weight and high weight and binge eating disorder. . . that's where epidemiologists have done a lot" (P16) Additional participant statements related to subtheme iii, "validity of negative health consequences" "I see metabolic disorder as being one of the . . . scare tactics used when [addressing] an obesity epidemic: 'look, [obesity is] associated with higher rates of metabolic disorder and high blood pressure, ' and . . . [there are] certain things that are associated with, but there are definitely people with binge eating disorder, or people with obesity, who don't have any of those problems. . . . In other words, they don't have metabolic syndrome. They don't have high blood pressure, they don't have diabetes, and yet . . . obesity has been declared a disease like a disorder" (P38) "We do have this really strong assumption, and I think this weight stigma as well, that [is] shared by [some] physicians [but not all, and represents a] view in the general population that all overweight is unhealthy and that any degree of overweight must be bad for your physical health, and you must improve your physical health with any degree of weight loss. And that's just simply not true. I think that's weight stigma as well. . . . We need to address that" (P93) Results expressed as n (%). Percentages: n/14 times 100. a That are associated with weight and can contribute to-and/or exacerbate BED symptoms. b E.g., metabolic disorder, diabetes, hypertension, and hypercholesterolemia. BED, binge eating disorder.
disorder. These included: (a) obesity contributing to weight stigma and resulting trauma that can contribute to and/or exacerbate binge eating disorder symptoms ( "I do think there are individuals whose bodies interact with things in our environment that might cause maybe inflammatory responses, or . . . disruption of the gut biome . . . where they might be naturally inclined toward weight gain -. . . maybe they are obese so they might be naturally inclined toward weight gain, or they have other medical issues that could make them inclined toward weight gain -so now you've got somebody who's got something going on inside of them, leading to weight gain that then leads them to [food] restriction that then leads them to binge eating." (P7) Subtheme iii: Validity of links to negative health consequences ( %) Two participants (2/14, 14%) expressed views that obesity can increase risk for medical complications and two participants (2/14, 14%) stated that not everyone with obesity has negative health consequences (e.g., metabolic disorder, diabetes, hypertension, hypercholesterolemia). And to what extent are we looking at something that's much more complicated -is it inflammatory? Is it mediated by the microbiome? I don't know. But . . . we need to consider it because we need to look at it, we need to make sure we're not stigmatizing our patients around it. Obviously, it needs to be treated, you know, we need to be really, of course, looking out for diabetes risk but at the same time, you need to make sure you're not putting people with a history of binge eating on too much of a restrictive diet. I mean, if they end up being shamed around their eating, it just makes the whole situation worse." (P72) " All 14 participants spontaneously identified a relationship between binge eating disorder and food/eating restriction, whether voluntary (e.g., self-elected dieting) or involuntary (e.g., imposed by a parent, medical provider, or economic conditions) (14/14, 100%) ( Table 5). Three subthemes were identified: (i) the relationship between restriction and binge eating (100%); (ii) spontaneously identified forms of restriction (43%); and (iii) factors contributing to restriction (43%).

Subtheme i: Relationship between restriction and binge eating ( %)
All participant statements addressed the existence of a possible relationship between restriction and binge eating (14/14, 100%) ( Table 5). Eleven participants expressed views that restriction can or does lead to binge eating (11/14, 79%). Two additional participants described this view as being endorsed by cognitive behavioral therapy and in the field but did not endorse or negate the view personally (2/14, 14%). Three participants described food restriction as a predominant phenotype of binge eating disorder (3/14, 21%). Two participants expressed perceptions that a high prevalence of restriction exists among individuals with binge eating disorder, whether the individuals themselves realize it or not (2/14, 14%). Two participants also expressed views that restriction may index distress about weight or pre-existing binge eating (rather than directly causing binge eating) (2/14, 14%). Select quotes from participants regarding the relationship between restriction and binge eating disorder are shown below and in Table 5.
"The most common behavior that anybody does before they binge is they restrict, that's what they do before they binge." (P7) "Any restrictions on food will lead to more binges." (P37) "[Research finds] that . . . there's diversity in the phenotype of binge eating disorder, with . . . one group ["about half "] . . . being more . . . restrictive-focused, and another group . . . having more issues with inhibitory control and cravings, and emotion dysregulation." (P19) "There's . . . a worry . . . in the eating disorder field that dieting causes binge eating. A lot of that data, I think, comes from crosssectional and follow-up studies, surveys of folks out in the world who were asked, 'are you dieting?' and then, 'are you binge eating?' or: 'are you dieting now?' and they follow them up and sometime later, they're found to have an increased frequency of binge eating compared to folks who were not originally dieting.
.... The problem is it's hard to know cause and effect [when interpretating that data]. These epidemiological-type studies find associations, but what you may be [indexing] with the dieting, . . . is distress about weight, as opposed to real food restriction, caloric restriction. So . . . it's hard to be sure exactly how to interpret [the data]. Maybe one interpretation is, indeed, [that] the dieting led people to binge eat, but it's not the only interpretation. And the data from . . . controlled trials where people are put on a diet under some sort of medical, psychological, or nutritional supervisionthe evidence that . . . clinically overseen dieting produces binge eating -is slim-to-none. . . . Now again . . . there are individuals who . . . certainly apparently cannot tolerate dieting without some real distress and behavioral disturbance, so I'm not suggesting anything otherwise. But as a general phenomenon, I don't think it's been established that dieting . . . always leads to untoward consequences." (P46, both paragraphs above) Subtheme ii: Spontaneously identified forms of restriction ( %) All participants (14/14, 100%) spontaneously identified different types of restriction, including (a) self-imposed dieting (11/14, 79%); (b) restriction coinciding with food scarcity or economic insecurity (9/14, 64%); (c) externally mandated (by a medical doctor or parents, often linked to weight) (2/14, 14%); and (d) restricting certain types of foods, food enjoyment, or calories (2/14, 14%) ( Table 6). Select quotes from participants spontaneously identifying forms of restriction are shown below and in Table 6.
"Chronic dieting is something that we are currently seeing more and more of where it becomes this binge-restriction cycle." (P37) "There is a group without question that is just hardwired to be higher weighted, and they are big-time restrictors." (P72) "Access to food is a big, big deal. . . . In households where there's . . . food scarcity, [that] can lead to binge eating. You don't know .

Subtheme (i) relationship between restriction and BED ( %)
Can or does lead to binge eating 13 (93%) Expressed a personal view that restriction can/does lead to binge eating 11 (79%) Described a perspective that restriction can/does lead to binge eating as being endorsed in the field, but did not endorse or negate the view personally 2 (14%) Perceive high prevalence of restriction among individuals with BED 2 (14%) Restriction may index distress about weight or pre-existing BED a 2 (14%) Additional participant statements related to subtheme i, "relationship between restriction & BED" "There is a group without question that is just hardwired to be higher weighted, and they are big time restrictors" (P72) "About a third [of my clients] described dieting and want to stop that cycle, but it actually is binge eating disorder" (P37) Results expressed as n (%), in which percentages are n/14 times 100. a Rather than directly causing binge eating.
BED, binge eating disorder. Additional participant statements relating to subtheme ii, "forms of binge eating" "About a third [of my clients] described dieting and want to stop that cycle, but it actually is binge eating disorder" (P37) "I work with patients who have said, 'well yeah, I have binge eating.' I binge eat the first two weeks of the month 'cause that's when we have food in the house and then there's no food in the house the last two weeks of the month.' That's a systemic issue that I think needs to be addressed and needs to be talked about in terms of people's vulnerability to eating disorders" (P75) "When you put somebody on a diet, it's a medical intervention, . . . you're doing something physically to their body, and to their mind, so that's under the realm of . . . biological [interventions] because restriction and cutting someone's calories or cutting food groups or telling them to . . . count carbs, or keep points, or count calories, or whatever . . . that's really external regulation" (P7) Results expressed as n (%), in which percentages are n/14 times 100. a Often linked to weight.
when you're getting your next meal? And it's in front of you? And you're really, really, really hungry because you haven't eaten in a while. And then there's food around? What do any of us do when we're really hungry? We eat. Our brain[s]. . . -we -are in food-seeking mode, we're hungry, we're deprived, we're mentally deprived, we haven't enjoyed the pleasure of it, we're physically hungry, our body says to eat." (P7) "I've worked with hundreds of people, it feels like, who have a story that goes something like, 'well, . . . when I was a kid, I had this big appetite and my parents, it really freaked them out, so they started to put me on a diet or lock up the food or put me in Weight Watchers or whatever, because they were worried I would get fat, ' and particularly . . . when genetically that person was just going to be a little bit larger-bodied anyway, that fear of fatness was introduced at such an early age and connected to the limiting of food, and we know that people who go on a diet are more likely to gain weight, so it's a self-perpetuating cycle that is really not helpful." (P60) Subtheme iii: Underlying factors contributing to restriction ( %) Foci a: Specific/micro factors ( %) Seven participants spontaneously identified eight different factors contributing to restriction (7/14, 50%; Table 7), including: (a) body weight/shape/size (especially in naturally higher-weighted individuals, 4/14, 29%); (b) restricting to soothe or cope (2/14, 14%); and (c) shame around eating (2/14, 14%). Additional specific factors identified by one participant (1/14, 7%) each are included in Supplementary material S2.1.
"The actual restriction of food. . . deprivation, restriction, the mandate to not eat, the shame that's induced at a very early stage in one's life related to eating, related to hunger, related to body size, that's an interpersonal experience that is tied in with our weight-obsessed society, where there's a culturally-driven mandate to be a body size and shape that oftentimes is incongruent with our . . . pre-determined natural body weight." (P7) .
Theme : Negative a ect, distress, and emotion regulation ( %) Subtheme i: Negative a ect ( %) Foci a: Negative a ect addressed verbatim ( %) Negative affect was addressed verbatim by seven participants (7/14, 50%; Table 8). Six participants described negative affect as driving binge eating (6/14, 43%). Three participants (3/14, 21%) described a mechanism by which binge eating is used to reduce or alleviate negative affect; two participants referenced literature supporting this possibility (2/14, 14%). Two participants suggested negative affect makes binge eating disorder and its associated symptoms more difficult to manage, in part through the added burden of managing binge eating disorder with a concurrent mood disorder. One participant (1/14, 7%) suggested negative affect can contribute to increased risk for binge eating disorder (and referenced work supporting this possibility).
"A lot of . . . work has looked at the role of emotional or affective factors. . . . we . . . see, for example, we think that difficulties with negative affect play a role in risk for binge eating at some level. I think . . . the conceptualization would still sort of cycle back to . . . the question[s] of 'why does this person have high levels of negative affect?' Or 'why does this person have difficulty -when encountering high levels of negative affectwith managing that?' And it's very tempting . . . to draw lines back to environmental and genetic factors to help explain that." (P5) "We know that negative effect is often a driver for binge eating and . . . not just in terms of onset of eating disorder, [but] also [in terms of] managing this disorder with a concurrent mood disorder." (P93) Foci b: negative a ective states ( %) Ten (10/14, 71%) provided descriptions of negative affective states (10/14, 71%; Table 8). These included: (a) guilt (6/14, 43%), (b) shame (6/14, 43%), (c) poor self-esteem (5/14, 36%), and (d) self-hate (2/14, 14%). "I've had a client . . . literally ask me if God hates her." (P37) "We know that one of the things that is so ubiquitous with binge eating disorder patients is just the amount of guilt and shame that they are carrying around with them, . . . the. . . constant feedback loop of 'I can't believe I did this; I'm so ashamed of how much I ate; I'm ashamed of what I ate; I did this secretively in my car; I don't want anybody to know.' I've worked with patients who have spent just huge amounts of money on food that they don't have and that adds to the shame and the guilt that we see with these episodes. . . . I think the amount of . . . emotional and cognitive burden that these folks are carrying around can't be understated." (P75) ". . . I think . . . if you couple [the cognitive burden of guilt and shame described in P75 quote above] with also living in a higher-weighted body -which many individuals with binge eating disorder have -there is an additional burden of weight stigma that not only do they face from the outside world, but they also internalize, so maybe they beat themselves up for living in a larger body and think, 'see, you're just doing this to yourself because you're engaging in these binge eating episodes, ' and certainly we know that shame is not a good motivator for behavior change, so they just get stuck in these cycles that I think are really pernicious" (P75) Foci c: Underlying mechanisms ( %) Five participants (5/14, 36%) identified mechanisms relating negative affective states to binge eating disorder (Table 8). These included: (a) binge eating behavior being linked to negative affective states (5/14, 36%), including guilt (4/14, 29%), shame (3/14, 21%), and self-esteem (1/14, 7%); (b) binge eating behavior being linked to body image (2/14, 14%), including shame and low self-esteem (1/14, 7% each); and (c) binge eating driving negative affect through induction of subsequent withdrawal [e.g., opponent-process theory (38, 39 "I do think that there's conssiderable empirical support for the idea that reward models are helpful. Whether they're brain based or just experiential reward, the idea that -in some fashionthe binge eating experience either reduces negativity, or perhaps induces a brief period of positivity in terms of emotional state, I think that has empirical support." (P33) .
Foci (c) mechanisms relating negative a ective states to BED ( %)  Results expressed as n (%), in which percentages are n/12 times 100, since 12 participants addressed this theme. a In part through the added burden of managing a concurrent mood disorder. b Six participants did not use the term "negative affect" directly; four did. c Including binge eating and loss of control.
"I think . . . if you couple [the emotional and cognitive burden that these folks are carrying around] with also living in a higher-weighted body -which many individuals with binge eating disorder have -there is an additional burden of weight stigma that not only do they face from the outside world, but they also internalize, so maybe they beat themselves up for living in a larger body and think, 'see, you're just doing this to yourself because you're engaging in these binge eating episodes, ' and certainly we know that shame is not a good motivator for behavior change, so they just get stuck in these cycles that I think are really pernicious." (P75) .

Subtheme ii: Distress ( %)
Distress was addressed by nine participants (9/14, 64%) ( Table 9). Five participants described distress as central to binge eating disorder pathology (5/14, 36%) and four described it as impacting binge eating disorder development (4/14, 29%). Three participants identified distress as central to self-identification and treatment-seeking for binge eating disorder (3/14, 21%). Three participants recognized distress a central DSM diagnostic construct (1) and three described distress as a key criterion that differentiates individuals with binge eating disorder from those with overweight, obesity, or loss of control eating (3/14, 21% each).
"The main problem is this distress regulation in the first place." (P53) "Clearly, folks with binge eating disorder -or at least those folks who show up for treatment -have increased anxiety, increased depression, increased distress, . . . a lot of guilt, and have certainly over-concern with [body] shape and weight, compared to similarly sized peers." (P46) "One of the DSM criteria basically calls for distressextreme distress -about the behavior [of binge eating] and so these folkscertainly, on average -are quite distressed, psychologically, more than their peers, and including distress about the behavior. So . . . Nine participants identified emotional regulation or negative urgency as being central to binge eating disorder pathology (9/14, 57%; Table 10). Two participants referenced empirical support (2/14, 14%). Six participants described a paradigm in which binge eating is used as a strategy for regulating, stabilizing, or coping with emotions or negative affect (6/14, 43%). One participant discussed emotion regulation as being related to food-and serotonin dysregulation (1/14, 7%). One participant questioned the impact of emotion regulation on binge eating disorder pathology, stating emotion regulation interventions have not been found to differ in their effectiveness from guided selfhelp cognitive behavioral therapy, suggesting the pathology may be equal parts emotional and cognitive behavioral.  Additional participant statements related to theme , subtheme ii, "distress" "There's distress around the binge eating that can be emotional but I think [it is] really core. . . " (P93) "People who self-identify as having binge eating disorder are-in my mind-a distinct subgroup from people with obesity in that they experienced that sense of loss of control, they're often more distressed about their eating patterns. They have more comorbidity. And there's certainly a lot of data that their healthcare utilization costs are higher. That may be psychiatric. I don't I don't think that's clear" (P72) "Binge eating disorder, . . . is defined really solely on the behavior of binge eating and the second criteria of diagnostic specifiers, and the third criteria is marked distress regarding binge eating" (P93) Results expressed as n (%), in which percentages are n/12 times 100, since 12 participants addressed this theme. a APA (1).
BED, binge eating disorder; DSM, diagnostic and statistical manual of mental disorders.  Results expressed as n (%), in which percentages are n/12 times 100, since 12 participants addressed this theme. BED, binge eating disorder.
only causal factor, but I think, certainly, emotion dysregulation is a big part of it. . . " (P72) "It certainly seems to play out in the trait-based literature so far that people who struggle with bulimia and binge eating sort of tend to be a little bit more impulsive and dysregulated." (P60) Theme : Diagnostic heterogeneity and validity ( %) Ten participants (10/14, 71%) expressed views related to the diagnostic validity and/or heterogeneity of binge eating disorder (Table 11).
"I think there's a subgroup of people [who] either because of their inhibitory mechanisms or the reward mechanisms . . . really struggle with [being able to eat their highest risk foods]. And they can probably do it in a restaurant, but. . . do we have to make them? . . . I don't think we understood heterogeneity of reward response or inhibitory mechanisms [when exposure to one's high-risk foods was the conventional training for treatment]." (P72) "[Based on] some of the neurocognitive data around inhibitory control, some of the cognitive remediation work that's coming out, it's pretty clear there's a subgroup of people [who] probably meet the phenotype that would be similar to sort of an ADD/ADHD kind of presentation, where you generally see inhibitory issues or . . . potentially a reward responsivity. . . " (P72) One participant (1/14, 7%) identified three possible phenotypes or subgroups that cut across all eating disorders (one group with high levels of perfectionism, control, and obsessive-compulsive tendencies, one group with disordered eating but low psychopathology, and one group with higher impulsivity).
"If you have a group of people with anorexia, a group of people with bulimia, a group of people with binge eating disorder [and] a group of people with obesity, it doesn't matter how you define it, you almost always end up with three groups: you end up with a group that is traditionally considered [as having] over-control . . . high, obsessive compulsive rates, high levels of perfectionism, you've got a group that has the eating disorder, and then pretty low psychopathology, and then you've got a group that [is] more impulsive." (P72)

Subtheme ii: Diagnostic validity ( %)
Five participants (5/14, 36%) expressed skepticism of-or limitations in the current diagnostic criteria for binge eating disorder.   Results expressed as n (%), in which percentages are n/14 times 100. a Driven by mechanisms implicit in substance-related and addictive disorders (e.g., hedonic/reward-based symptoms). b Having issues with "inhibitory control, " "impulsivity, " and "craving" or "reward responsivity". c For example, obsessively thinking about food or compulsivity around eating food.  Theme : Paradigm shifts in understanding binge eating disorder ( %) Subtheme i: Anorexi-centric paradigm for understanding binge eating disorder ( %) Five participants described an "anorexic-centric" paradigm that has historically been used for understanding binge eating disorder pathology, epidemiology, and treatment (5/14, 36%; Table 12).
"How we think about eating disorders is that . . . anorexia was kind of the granddaddy, . . . the thing we knew first, and then bulimia kind of grew out of that next, and . . . people used to refer to [ Four participants expressed views that eating disorder research has historically focused more on anorexia nervosa and bulimia nervosa vs. binge eating disorder (4/14, 29%; Table 12). "There's so much less research on binge eating disorder than [on] anorexia nervosa or bulimia nervosa." (P16) "A lot of [research is done in] more intensive levels of care than outpatient, and people with binge eating disorder are not as much represented there as people who have anorexia or bulimia." (P5) Foci b: "Anorexi-centric" understanding of who can have an eating disorder ( %) Three participants described a historically "anorexi-centric" understanding of who can have an eating disorder (e.g., ascribing eating disorders to thin, white, affluent, cis-gendered neurotypical females) (2/14, 14%; Table 12). "We know that unfortunately eating disorders have been hampered by these old stereotypes about who's affected, and that leaves millions of people undetected with an eating disorder. . . . The number of people that I've seen and done evaluations on who are really surprised to learn that the way that they've been eating is actually considered disordered and that they have an eating disorder and I think that that's especially true for . . . any individuals that don't fit that stereotypical mold of who has an eating disorder . . . Subtheme ii: Paradigm shift in understanding drivers for binge eating disorder ( %) Four participants described a shift in our understanding-as a field-of the mechanisms that can drive binge eating disorder (4/14, 29%; Table 12). Participants described old paradigms as focusing on voluntary intentional food/eating restraint (e.g., intentional fasting, see Theme 5) (endorsed by 2/14, 14%) and body weight/shape/size over-valuation and dissatisfaction (endorsed by 2/14, 14%) as driving binge eating. Participants described new paradigms as focusing on the roles of emotion regulation ( [and] binge eating -which I think it's still valid, obviously -but I think there's been also greater understanding of the role of emotions and mood and negative affect as [driving] binge eating, and then we have that shift in our . . . understanding of people with mood intolerance and various forms of personality vulnerability -who we do see as well, quite often -and it's often that the binge eating is a form of emotion regulation, similar to other forms of emotion regulation, that [a patient] may present with, and I think that's led us to an understanding of different forms of psychological therapy [for binge eating disorder]." (P93) "As a field . . . we neglect social anxiety disorder because we tend to think it's just about weight and shape, self-consciousness, I think we under-diagnose this. . . . we need to be looking specifically at Social Anxiety Disorder and I think based on Janet Treasurer's work, we're going to end up seeing that there's links in . . . sensitivity to social threat, . . . the extent to which that's causal, secondary to the eating disorder . . . understanding where anxieties sort of intersect and [understanding the] neurocognitive process . . . especially around threat sensitivity. . . is going to be really helpful." (P72)

Theme : Research gaps and future research directives ( %)
Two subthemes were identified regarding gaps in the literature and future research the experts would like to see closed related to the above topics: (i) Seven experts (7/14, 50%) identified a need for a better understanding of the relationship between binge eating disorder and overweight and/or obesity, including: (a) a need for clarification around the extent to which binge eating disorder and obesity are separate vs. related/overlapping (4/14, 29%); (b) greater clarification and understanding of how binge eating disorder differs from overweight and/or obesity (3/14, 21%); (c) what health risks and metabolic implications are associated with binge eating (2/14, 14%); and (d) prevalence of binge eating disorder in large and small body sizes (1/14, 7%) (Table 13). (ii) Three experts (3/14, 21%), identified classification issues as an area warranting further research, including: (a) whether binge eating disorder is a viable disorder (1/14, 7%); (b) understanding the eating behavior of individuals with binge eating disorder as it occurs in the real world (1/14, 7%); and (c) consideration of reclassification of binge eating disorder with other eating disorders of recurrent binge eating (e.g., bulimia nervosa and binge-purge-type anorexia nervosa) (1/14, 7%).

Novelty and innovation
To the authors' knowledge, our study is among the first to synthesize expert opinion on clinical factors pertaining to adult binge eating disorder pathology (and among the first to synthesize expert opinion on aspects of adult binge eating disorder in general). Synthesizing expert opinion isn't common in the binge-eating field. As such, this novel study that describes clinical factors pertaining to binge eating provides insights and expands upon several themes influencing the recognition of binge eating disorder, highlighting its heterogenous presentation and challenges in its clinical diagnosis, ultimately impacting management strategies. Exploring several themes and identifying novel viewpoints enables hypothesis-generating questions previously unexplored, or only explored within a limited capacity.
Most recently, a 2020 latent class analysis investigating potential sources of heterogeneity among 775 treatment-seeking adults with overweight or obesity and binge eating disorder identified two classes of individuals with binge eating disorder who differed in body image concerns, distress about binge eating, and depressive symptomatology (42). The number of binge eating episodes was also significantly different between the two classes; whereas body mass index (BMI) was not a significant covariate in most models. The findings led the authors to critique the way we currently define binge eating disorder diagnostically, as current features used for diagnosis fail to adequately explain presenting heterogeneity. The study suggests there appear to be distinct subgroups within binge eating disorder, which was exposed by at least one of the experts interviewed here.
The important findings of our study in addition to the existing literature highlight the ongoing evolution in our understanding of heterogeneity in binge eating disorder, refining its diagnostic criteria, and pursuit for suitable management strategies outside of the constructs already dominated by anorexia nervosa and bulimia.

Relationship of findings to existing literature
Theme : Obesity domain ( %) The experts' general recognition that obesity and binge eating disorder are commonly-but not always-linked (theme 1, subtheme i) aligns with current incidence and prevalence estimates (13)(14)(15)(16), however, the nature of the relationship is less clear amongst interviewed experts. The experts' emphasis on the role of body/weight/shape stigmatization (theme 1, subtheme ii) seems to align with psychological contributions to intense concerns about body weight/shape/size overvaluation and heightened incentive for change (17). Evidence suggests comorbid obesity and binge eating disorder is associated with more severe and prevalent levels of mental health disorders and negative affect than those observed in individuals with obesity or binge eating disorder alone (43-46).
Meanwhile, findings on physical health outcomes associated with comorbid obesity and binge eating disorder seem less clear, as recognized by the experts (theme 1, subtheme iii). A small observational study published in 2009 found 66% of treatmentseeking individuals with binge eating disorder and obesity had metabolic syndrome, with men and whites having significantly higher rates than women and African Americans, respectively (47). However, in this study, neither self-reported frequency of binge eating, nor severity of eating disorder psychopathology significantly differed among individuals with-vs. without metabolic syndrome. More recently, a 2014 factor structure analysis of metabolic syndrome in 347 individuals with obesity and binge eating disorder found .
/fpsyt. .  metabolic syndrome factors (e.g., obesity, glucose regulation, blood pressure, and lipids) do not significantly differ in individuals with binge eating disorder and obesity vs. those found in normative population studies (48). However, authors suggested "moderate attempts to regulate food intake may reduce the negative impact of obesity and binge eating pathology on metabolic function", (48). Furthermore, a 2008 review questions the validity of using obesity as a diagnostic criterion for binge eating disorder as the distress and psychopathology associated with binge eating disorder are not primarily due to obesity (19).

Theme : Intentional/voluntary or unintentional/involuntary restriction ( %)
The experts' general views that food restriction can or does lead to binge eating (theme 2, subtheme i) aligns with that of cognitive behavioral therapy (CBT), the first-line therapeutic intervention for any eating disorder, including binge eating disorder (3,5,6), which posits that dieting behavior drives binge eating and results from overevaluation of eating and body weight/shape/size (3). However, CBT fails to produce longstanding remission in ∼50% of individuals with binge eating disorder (49), suggesting possible limitations in this view that are supported in the literature (7,(50)(51)(52).
The relationship between dietary restraint and economic precarity has recently gained recognition in the field (18). Here, food scarcity was recognized as a common form of food restraint by most experts, second to dieting (theme 3, subtheme ii). This recognition aligns with findings from several studies conducted at a food pantry in San Antonio, TX between 2015 and 2016 (53-55). These studies found 90% of respondents had a clinically significant eating disorder (55), with eating disorder pathology severity significantly correlating with deliberately trying to limit food consumption or going >8 h without food consumption (r = 0.25, p = 0.0001), which 52% of respondents reported (53). Reasons for food/eating restraint included lack of resources, SNAP/food stamps being insufficient, and emphasizing other family members receive access to food (53). More recent findings suggest binge eating disorder is 1.65 times more common in indivdiuals with food insecurity (8.6% prevalence vs. 5.2% prevlance in foodsecure indivdiuals; p = 0.02) (56) and both food insecurity and/or receiving government assistance before age 18 are both associated with increased odds of having binge eating disorder (57,58).
Theme : Negative a ect, distress, and emotion regulation ( %) In line with general expert recognition of the links between negative affect, distress, emotion regulation, negative urgency, and binge eating (theme 3), literature supports adult binge eating disorder linked to psychosocial dysfunction across a wide range of domains, including affect and emotion regulation (59). The majority experts' identification of negative affect, emotion dysregulation, and negative urgency as driving binge eating (theme 3) aligns with emotion/affect regulation models, which are well-supported in the literature (4). This recognition also aligns with a paradigm shift in the field from a historical tendency to attribute all eating disorders to overvaluation of eating behavior and/or body weight/shape size and resulting dietary restraint (e.g., dietary restraint and dual pathway models) (3,4,7) to a more encompassing view of binge eating disorder as a heterogenous disorder with multiple possible underlying mechanisms and room to accommodate multiple conceptual models (4,18). This trend was also recognized by several experts (theme 5). Experts also reflect a belief that research investigating directionality of the associations between binge eating and negative affect, emotion dysregulation, and negative urgency is needed, as is reflected in the literature (59).
The concept of alexithymia is also one that warrants discussion alongside the topic of emotion regulation processes. Alexithymia is a subclinical phenomenon involving a lack of emotional awareness thought to result from difficulty in identifying and describing one's feelings and in distinguishing feelings from bodily sensations of emotional arousal [(60) as cited in (61)]. The involvement of alexithymia in anorexia nervosa and bulimia nervosa has been demonstrated in the literature (62). The involvement of alexithymia has also been documented in individuals with obesity (without eating disorder diagnoses), both by self-report (63) and implicit measure (64). Several evidence are also available in the literature indicating the role of alexithymia in binge eating disorder (62,65). Interestingly, the concept of alexithymia was only addressed specifically by one participant in this study (P72 , Table 10). This participant's statement captures the intertwined relationship between alexithymia and emotion regulation. Future research investigating  93% of experts expressed views that restriction can or does lead to binge eating (theme 2, Table 5) Dual pathway models Body dissatisfaction viewed as leading to binge eating through restrained eating and negative affect (7) Not directly, though see columns 5-6 N/A 29% of experts identified body weight/shape/size as a factor contributing to restriction and 14% of experts described restricting to soothe or cope (theme 2, subtheme iii, Table 7) 43% of experts described a paradigm in which binge eating is used as a strategy for regulating, stabilizing, or coping with emotions or negative affect, though not necessarily linked to body dissatisfaction (theme 3, subtheme iii, Table 10) 14% of experts described an old focus on body weight/shape/size overvaluation/dissatisfaction and restriction as driving binge eating, and a new understanding of the role of emotion regulation as a driving factor (theme 5, All experts identified associations between negative affect and binge eating (100% endorsement: theme 3, Table 8) 43% of experts described a paradigm in which binge eating is used as a strategy for regulating, stabilizing, or coping with emotions or negative affect, though not necessarily linked to body dissatisfaction (theme 3, subtheme iii, Table 10) 14% of experts described an old focus on body weight/shape/size overvaluation/dissatisfaction and restriction as driving binge eating, and a new understanding of the role of emotion regulation as a driving factor (theme 5,   Table ) Other expert views that align with this model/theory Transdiagnostic model Expanded conceptualization based on the original cognitive-behavioral theory of bulimia nervosa (5, 70, 71) that suggests a dysfunctional scheme for evaluating the self-including overvaluation of body weight/shape/size and eating behavior and perfectionistic tendencies-result in low self-esteem that promote extreme and maladaptive weight control behaviors that prompt a cycle of dieting/weight loss and refractory binge eating (4,5) This was not directly identified as a theme, though see columns 4-5 "Chronic Dieting/Restriction-mediated" subtype (endorsed by 21% of experts) partly aligns with this model Participant descriptions of negative affective states (theme 3, subtheme i, foci b) and possible mechanisms relating negative affective states to BED (theme 3, subtheme i, foci c) support a view that overvaluation of eating behavior contributes to poor self-esteem, which perpetuate binge eating behavior and psychopathology Weight regulation models View weight and weight history as causal variables with clinically significant impacts on ED psychopathology and perpetuation (17) Though expert statements aligning with weight regulation models was not identified as a theme, obesity was (theme 1) N/A Although multiple links were identified between obesity and BED in theme 1, none of the experts in this study identified obesity or weight history as impacting or perpetuating BED psychopathology when specifically addressing the topic of obesity (theme 1) 93% of experts expressed views that restriction can or does lead to binge eating (theme 2, Table 5) 29% of experts identified body weight/shape/size as a factor contributing to restriction (theme 2, subtheme iii, Table 7) In the theme of restriction (theme 2 subtheme ii), 2 experts (P37, P60) described a pathology in which a natural predisposition for being higher-weighted results in internally-or externally imposed food/eating restriction, which induces or perpetuates a binge-restriction cycle or ED psychopathology Two participants also expressed views that (1) AN, BN, and BED each contain the same three subgroups of: (a) control-driven individuals with high obsessive-compulsive rates and high levels of perfectionism; (b) individuals with low ED psychopathology but disordered eating; and (c) individuals with higher impulsivity (P72) and (2) re-classification of eating disorder diagnoses with recurrent binge eating (e.g., BED, BN) should be considered based on similar subsets observed within the different diagnoses [e.g., "the degree of over-obsessionality [and] over-control, or impulsiveness and under-control" that underpin the ED behaviors (P93) (theme 4, subthemes i and ii)].
Columns 1 and 2 provide information on 12 different models/theories/conceptualizations of binge eating disorder supported in the literature (4). Column three shows whether the theme/model/conceptualization was identified as a theme among expert responses. Column four shows whether experts identified a binge eating disorder subtype of phenotype in theme 4, subtheme i ( Theme : Diagnostic heterogeneity and validity ( %) The experts' recognition of heterogeneity in binge eating disorder aligns with the literature, in which upwards of seven different models of binge eating disorder conceptualization have empirical support (4). Interestingly, the possible binge eating disorder subsets or phenotypes spontaneously identified or referenced by the experts tend to align with various models/conceptualizations of binge eating disorder (Table 14).
Recognizing, accepting, identifying, and classifying heterogeneity in binge eating disorder is an important step toward matching client heterogeneity to treatment modality, as has been done successfully in other disorders (72). Future research needs to address concerns quantifying binge episodes and confirm whether additional objective criteria for "binge size" aids diagnostic validity.
Fortunately, progress to this end is underway. For example, a 2020 latent class analysis investigating potential sources of heterogeneity among 775 treatment-seeking adults with overweight or obesity and binge eating disorder identified two classes of individuals with binge eating disorder who differed most distinctly across differences in body image concerns, distress about binge eating, and depressive symptomatology (42). The findings led the authors to critique the way we currently define binge eating disorder diagnostically, suggesting "many features currently used to define binge eating disorder (e.g., binge-eating frequency) are not helpful in explaining heterogeneity among individuals with [the] disorder. Instead, body image disturbances, which are not currently included as a part of the diagnostic classification system, appear to differentiate distinct subgroups of [these] individuals... Future research examining subgroups based on body image could be integral to resolving ongoing conflicting evidence related to the etiology and maintenance of binge eating disorder, " (42). These important findings represent the ongoing evolution in our understanding of heterogeneity in binge eating disorder, and our ongoing evolution in refining binge eating disorder as a diagnosis.

Theme : Paradigm shifts in understanding binge eating disorder ( %)
Despite advances in the field of binge eating disorder, over one-third of interviewed participants continue to ascribe to an "anorexi-centric" understanding of binge eating disorder pathology, epidemiology, and treatment (theme 5, subtheme i). As described previously by Bray et al. (18), an overwhelming majority of individuals satisfying DSM criteria for binge eating disorder fail to achieve an accurate diagnosis and/or receive adequate treatment (18). Furthermore, several minority and/or marginalized populations have a greater prevalence of binge eating disorder than the predominating white, cis-gendered, and heterosexual female described within the context of the "anorexi-centric" paradigm (18,(73)(74)(75)(76)(77)(78). This phenomenon may result from reduced recognition and screening for binge eating disorder in minority and marginalized populations, which may result in turn from an "anorexi-centric" understanding of binge eating disorder and can further reinforce that understanding.
Overall, experts' recognition of our growing awareness of who can have an eating disorder (theme 5, subtheme I, foci b), the ways binge eating disorder differs distinctly from anorexia nervosa and bulimia nervosa (theme 5, subtheme i), and the heterogeneity in binge eating disorder factors and psychopathology that exists beyond dieting attempts are reflective of this recognition in the literature. These paradigm shifts offer hope for greater diagnostic specificity and treatment outcomes for this significant national and global health problem.

Clinical implications
Our results call to light the need for a better understanding of the relationship between binge eating disorder and overweight and/or obesity, including a need for clarification around: (1) the extent to which the two health issues are separate vs. related/overlapping; (2) the validity of alleged health risks and metabolic implications associated with binge eating; and (3) the prevalence of binge eating disorder among individuals in large and small body sizes (theme 1, theme 6).
Further, while most experts expressed views about binge eating disorder psychopathology that align with dietary restraint models and emotion dysregulation models, a minority of experts recognize a historic trend in the field to view binge eating disorder as an extension of anorexia nervosa and bulimia nervosa. The experts also recognize a shift in these old paradigms toward greater recognition of who can have an eating disorder and around the heterogeneity that exists within the binge eating disorder diagnosis. It is important for clinicians to remember that the anorexi-centric stereotype of who can have an eating disorder (e.g., thin, White, affluent, cisgendered, neurotypical females with anorexia nervosa) is outdated, and that binge eating disorder has a uniquely higher prevalence among racial, ethnic, sexual, gender-, and socioeconomic minorities [as also identified in (18)]. Thus, our findings also underscore the importance of equal and adequate screening for binge eating disorder across race, ethnicity, sexual and gender orientation, body weight/shape/size, and socioeconomic status. It is also important to identify ways to include marginalized individuals who do not have access to adequate information, screening, or treatment in binge eating research and help find treatment interventions accessible to them [see (18,79)].
Lastly, our findings underscore the need for ongoing research on heterogeneity among binge eating disorder and for ongoing discussion and investigation of the way in which we diagnose and classify binge eating disorder. Improving diagnostic accuracy and specificity can help improve treatment specificity and outcome measures in turn.

Study limitations and strengths
Although it would have been interesting to analyze interview transcripts with the specific question of which theoretical and conceptual models of binge eating disorder were spontaneously endorsed by experts [such as those identified by (4)], to do so would contradict the open-ended methodology of reflexive thematic analysis. Thus, the authors did not analyze transcripts with any .
/fpsyt. . conceptual models in mind and were blind to any information on various conceptual models prior to their analyses of the interview transcripts. We feel that overall, this nuance makes the analysis both unique, innovative, and more accurate and informative in its findings. The qualitative and reflexive nature of this analysis limit its reproducibility, as the themes identified by the researchers are subjective based on their independent and joint analyses. Furthermore, the qualitative analysis of expert interviews was conducted by two individuals (BB and HZ with aid of CB). Thus, we cannot assess how accurately the themes identified here represent the true themes valued by expert binge eating disorder researchers (including those in this study and those at large). However, limitations are standard in the field of reflexive thematic qualitative analysis and are not generally viewed as discounting the methodology as a whole (37).
As is also standard for most qualitative research, it is important to note the study's sample size (which is appropriate for a mixed methods analyses of this nature) limits the generalizability of the data's themes and conclusions to the field of binge eating disorder researchers and clinicians at large. Additionally, as has been pointed out in previous publications (18,19), one of the study's four possible eligibility criteria for researchers were NIH grant funding (Table 1), which presents a bias for including participants from the U.S. There were three other nationally independent eligibility criteria researchers could meet to be included in this study and the final study sample included participants from the UK, AU, and CA as well as from the US. Nevertheless, 50% of participants were from the US and including criteria for funding form other federal agencies could have improved the population representation of the study overall. Additionally, this study collected demographic data on sex assigned at birth but not on gender. This unfortunate oversight follows an old convention (asking for sex assigned at birth rather than gender) that fails to account for equity and diversity inclusion and collects information that is not demographically relevant (sex assigned at birth) but misses information that is more demographically relevant (gender).
This study utilizes several methodological strengths that counterbalance the limitations identified above. The study's systematic inclusion criteria (Table 1) provides strong population representation of academic and clinical experts who lead the field. This includes researchers with the greatest recent and historic funding and publication records and clinicians with high clinical and academic engagement and access potential (e.g., those most likely to be identified through google searchers by individuals with binge eating disorder). Second, the study sample includes a well-rounded balance of binge eating disorder experts, including PhD/SciD researchers, medical doctors (MDs), licensed therapists and dieticians (LPs, RDs, LDs), and intuitive eating specialists, healthcare administrators, and public health advocates (MPHs) ( Table 3).

Conclusions
Overall, our understanding of adult binge eating disorder as an autonomous eating disorder diagnosis continues to grow and expand. Experts most commonly endorse food/eating restriction and emotion dysregulation as important components of binge eating disorder psychopathology, which aligns with two common historically supported models of binge eating disorder conceptualization (dietary restraint theory and emotion/affect regulation theory). At the same time, some experts recognize a historical oversight of viewing binge eating disorder through a limited "anorexi-centric lens", particularly in relation to who is at risk for having an eating disorder and factors that drive binge eating. The experts identify several areas of binge eating disorder that continue to warrant further investigation. These include the extent to which binge eating disorder and obesity are separate vs. related/overlapping and improving our understanding of the heterogeneity that exists within the diagnosis. Overall, these results highlight the continual advancement of the field to better understand adult binge eating disorder as an autonomous eating disorder diagnosis.

Data availability statement
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

Ethics statement
The studies involving human participants were reviewed and approved by National University of Natural Medicine (NUNM) IRB (# HZ12120). Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements. Informed consent was obtained verbally without use of participant names, to protect participant anonymity.