Optimal management of night eating syndrome: challenges and solutions

Sleep-Related Eating Disorder

Sleep-related eating disorder is a non-rapid-eye movement parasomnia typified by recurrent episodes of eating/drinking following arousals, with associated partial/complete amnesia. Adverse health consequences and quality of life impairments are common. The condition can be idiopathic but most often accompanies unrecognized/untreated comorbid sleep disorders and/or is induced by psychoactive medications. As such, management consists of addressing comorbidities and removing potentially offending medications. While a thorough clinical history is often sufficient, additional sleep testing may help identify coexisting sleep disorders and/or other phenomena that may cause arousals. Limited data suggest benefit from topiramate and other medications in idiopathic or otherwise refractory cases.

Beat the Clock: Assessment of Night Eating Syndrome and Circadian Rhythm in a Sample of Greek Adults

The night eating syndrome (NES) is characterized by excessive food intake during the evening and night hours, with 25% of the daily intake being consumed post-dinner, paired with ep-isodes of nocturnal food intake, at a frequency of more than twice weekly. The NES has been associated with a misaligned circadian rhythm related to a delay in overall food intake, increased energy and fat consumption. The present cross-sectional study aimed to assess NES in a Greek population and evaluate possible links between NES and chronotype. NES was assessed using the Night Eating Questionnaire (NEQ), and circadian rhythm, sleep and mood were evaluated with the Sleep, Circadian Rhythms, and Mood (SCRAM) questionnaire. A total of 533 adults participated in the study. A relatively high prevalence of NES was revealed, with more than 8.1% (NEQ ≥ 30) of the participants reporting experiencing NES symptoms, depending on the NEQ threshold used. Most participants had the intermediate chronotype. NEQ score was positively associated with the morning chronotype, and SCRAM was negatively related to "Good Sleep". Each point increment in the depression score was associated with 6% higher odds of NES. The early identification of NES gains importance in clinical practice, in a collective effort aiming to reduce NES symptomatology and its detrimental health effects.

Association of participants who screened positive for night eating syndrome with physical health, sleep problems, and weight status in an Australian adult population

BACKGROUND

Night eating syndrome (NES) is a unique eating disorder characterised by evening hyperphagia and nocturnal ingestions which cause significant distress and/or impairment in functioning. Despite the growing literature, NES remains poorly understood and under diagnosed. As such, this study aims to compare the prevalence of physical health conditions in participants with NES when compared to participants without an eating disorder (ED) and participants with other eating disorders (including anorexia nervosa (AN), binge eating disorder (BED) and bulimia nervosa (BN)) in a general population Australian sample of adults.

METHODS

The data for this study were obtained from the 2017 Health Omnibus Survey (HOS) a multi-stage, cross-sectional survey, conducted by Harrison Research in South Australia. This current study focused on 2547 participants over 18 years of age and specific questions from this population survey including those related to participant demographics and health.

RESULTS

This study identified that participants who screened positive for night eating syndrome (spNES) when compared to participants with other eating disorders (ED) or no ED diagnosis, were significantly more likely to have an increased age, be female, have lower levels of education and have lower household income. Additionally, the spNES group was significantly associated with sleep apnoea (p = 0.031), insomnia or other sleep problems (p < 0.0001), increased BMI (p < 0.0001), increased levels of pain/discomfort and lower physical health-related quality of life. Hypertension, hypercholesterolemia, and diabetes were not significantly associated with the spNES group or the "other ED" group which included participants with AN, BED, BN.

CONCLUSIONS

Several physical health problems were found to be significantly associated with the spNES group including sleep problems, increased BMI, increased levels of pain and lower self-reported physical health-related quality of life. Consequently, future research exploring the complex interaction between NES and these medical conditions may provide further insight into the diagnosis, screening tools and management of NES. Additionally, this study highlights the need for future studies which use larger population-based samples.

LEVEL OF EVIDENCE

Level III. Evidence obtained from well-designed cohort or case-control analytic studies.

A Scoping Review on the Association between Night Eating Syndrome and Physical Health, Health-Related Quality of Life, Sleep and Weight Status in Adults

Night eating syndrome (NES) is characterised by recurrent episodes of night eating, evident through excessive food consumption after the evening meal or eating after awakening from sleep, often associated with significant distress and/or impairment in functioning. This scoping review was conducted according to PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews) guidelines. The search was conducted through the use of PubMed, Medline (OVID) and SCOPUS, to identify relevant articles published within the last 10 years. Search terms including "Night eating*" OR "NES" and Boolean phrases were used to refine the search. Additionally, the age of participants was restricted to 18 years and above, to ensure only adult participants were included. The abstracts of the remaining articles were used to screen for those that were relevant. From a total of 663 citations, 30 studies assessing night eating syndrome met the inclusion criteria to be included in the review. We found inconsistent associations of NES with higher body mass index (BMI), less physical activity, type 2 diabetes mellitus (T2DM) and poorer quality of sleep. These inconsistencies may have been due to the use of different measurement methods, lack of power from small sample sizes of NES in some studies and varying ages of participants, with associations being more likely to be found in higher-quality, representative populations than in university student samples. There were no associations of NES with T2DM in clinical populations and with hypertension, OSA and metabolic syndrome, but sample sizes were small. The impacts of NES on these medical conditions should be addressed in future, using well-sized and long-term studies involving representative populations of adults. In conclusion, NES likely has negative impacts on BMI, T2DM, physical activity, and sleep quality, which in turn may increase cardio-metabolic risk. However, further research is needed to elucidate the interaction between NES and its associated features.

Night eating syndrome subtypes: differences in binge eating and food addiction symptoms

PURPOSE

The purpose of the current study was to examine differences in binge eating and food addiction symptoms between Night Eating Syndrome (NES) latent subtypes: evening hyperphagia with nocturnal ingestions (EHNI), evening hyperphagia-only (EHO), and nocturnal ingestions-only (NIO). It was hypothesized that the EHNI group would report more binge eating behaviors and more food addiction symptoms than both the EHO and NIO groups. Further, it was hypothesized that the EHO and NIO groups would differ with the EHO group reporting more binge eating behaviors and the NIO group reporting more food addiction symptoms.

METHODS

Participants completed measures online relating to night eating, binge eating, and food addiction. Average age of the final sample was 34.3 (SD = 10.5) and 62.0% were men. Responses to the Night Eating Questionnaire (NEQ; Allison et al., 2008) were used to create an EHNI group (n = 65), an EHO group (n = 32), and a NIO group (n = 69). ANOVAs were conducted to examine between-group differences on disordered eating symptoms.

RESULTS

Participants in the EHNI group reported more severe binge eating and food addiction symptoms than those in the EHO and NIO groups. However, there were no significant differences in binge eating or food addiction between the EHO and NIO groups.

CONCLUSION

Individuals who meet both NES core criteria (evening hyperphagia and nocturnal ingestions) are likely at a higher risk for experiencing other, more severe disordered eating pathologies. Implications concerning assessment and future research on NES typology are discussed.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

An Updated Review of Night Eating Syndrome: An Under-Represented Eating Disorder

PURPOSE OF REVIEW

Night eating syndrome (NES) is an eating disorder that has historically been under-studied. The current review aims to summarize the most up-to-date research on NES to support better awareness.

RECENT FINDINGS

Since NES was recently included as a formal diagnosis, research on the prevalence of NES is ever evolving. Current studies underscore the high comorbidity between NES and other eating disorders, with additional complexities for patient with comorbid eating disorders. Recent findings also support the association between NES and sleep correlates, a relationship that has remained during the COVID-19 pandemic. Emerging research confirms correlates of distress in NES across cultures. There remain mixed findings between NES and BMI. There is also debate around whether age is a risk factor. Bariatric surgery research has focused on the re-emergence of NES post-operatively. Our understanding of the correlates of NES is increasing. However, research on the treatment for NES remains particularly under-studied and requires further attention.

The relationship between chronotype, night eating behavior and fear of COVID-19 in academics

Academics are an occupational group that works at an intense pace. The number of studies on chronotype and night eating behavior in academics is limited, and there is insufficient data on whether fear of COVID-19 is also a risk for developing eating disorders. This study aimed to investigate the relationship between chronotype and night eating syndrome (NES) and examine the influence of fear of COVID-19 on night eating behavior in academics. The study data were collected using the personal information form, "Morningness-Eveningness Questionnaire, The Night Eating Questionnaire (NEQ), and the Fear of COVID-19 Scale." According to the chronotypes of the academicians, it was determined that the score compatible with NES and the scores of the Fear of COVID-19 Scale differed statistically significantly, and the score compatible with NES and Fear of COVID-19 Scale scores were also higher in the evening type at a rate of 29.2% compared to other chronotypes (p < .05). The Fear of COVID-19 scale and Morningness-Eveningness Questionnaire scores were significantly correlated with the Night Eating Questionnaire (R = .391 R² = .153 p < .05). The variables of the Fear of COVID-19 Scale and the Morningness-Eveningness Questionnaire explained 15% of the total variance of the Night Eating Questionnaire scores. Considering that academics are a group that works without the concept of overtime and whose work intensity is high, it is clear that studies should be conducted to raise awareness to protect the physical health of academics and prevent the development of eating disorders. There is a need for studies that question the relationship between chronotype, diet, and health.

Prevalence and psychiatric comorbidities of night-eating behavior in obese bariatric patients: preliminary evidence for a connection between night-eating and bipolar spectrum disorders

PURPOSE

The co-occurrence of obesity, eating and mood disorders has been frequently reported in clinical and epidemiological settings. This study aimed to explore the prevalence of night-eating obese patients referred for bariatric surgery and to identify associated psychopathology and psychiatric comorbidity.

METHODS

The sample was composed of 121 obese patients consecutively enrolled between November 2010 and May 2012 during psychiatric evaluations for bariatric intervention. Clinical features and psychiatric diagnoses were collected. Night-eating was investigated through the administration of the Night-eating Questionnaires (NEQ) and was defined as the presence of self-reported evening hyperphagia and/or nocturnal ingestions. Binge-eating and purging behaviors and general psychopathology were respectively assessed using the Bulimic Investigatory Test, Edinburgh and the Symptom Checklist-90-Revised.

RESULTS

Night-eating was reported by twenty subjects (16.5%). Patients with night-eating behavior were significantly more frequently diagnosed with bipolar spectrum disorders and with comorbid eating and mood disorders in comparison with other patients. Night-eating patients showed significantly more binging/purging behaviors and greater severity of somatization, obsessive-compulsive symptoms, phobic anxiety, psychoticism and sleep disorders. Patients with bipolar disorder type 1 or 2 scored significantly higher than those without mood disorders at NEQ total score, mood/sleep and nocturnal ingestions subscales, but also scored significantly higher than other patients with mood disorders at the latter subscale.

CONCLUSION

Patients with evening hyperphagia and/or nocturnal ingestions should be carefully evaluated to detect possible bipolar spectrum disorders and other eating disorders. Prompt management of these conditions should be provided before bariatric interventions.

LEVEL OF EVIDENCE

V, cross-sectional descriptive study.

'In the night kitchen': A scoping review on the night eating syndrome

BACKGROUND

First described in 1955, night eating syndrome refers to an abnormal eating behavior clinically defined by the presence of evening hyperphagia (>25% of daily caloric intake) and/or nocturnal awaking with food ingestion occurring ⩾ 2 times per week.

AIMS

Although the syndrome is frequently comorbid with obesity, metabolic and psychiatric disorders, its etiopathogenesis, diagnosis, assessment and treatment still remain not fully understood.

METHODS

This review was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines; PubMed database was searched until 31 October 2020, using the key terms: 'Night Eating Syndrome' AND 'complications' OR 'diagnosis' OR 'drug therapy' OR 'epidemiology' OR 'etiology' OR 'physiology' OR 'physiopathology' OR 'psychology' OR 'therapy'.

RESULTS

From a total of 239 citations, 120 studies assessing night eating syndrome met the inclusion criteria to be included in the review.

CONCLUSION

The inclusion of night eating syndrome into the Diagnostic and Statistical Manual of Mental Disorders-5 'Other Specified Feeding or Eating Disorders' category should drive the attention of clinician and researchers toward this syndrome that is still defined by evolving diagnostic criteria. The correct identification and assessment of NES could facilitate the detection and the diagnosis of this disorder, whose bio-psycho-social roots support its multifactorial nature. The significant rates of comorbid illnesses associated with NES and the overlapping symptoms with other eating disorders require a focused clinical attention. Treatment options for night eating syndrome include both pharmacological (selective serotonin reuptake inhibitors, topiramate and melatonergic drugs) and non-pharmachological approaches; the combination of such strategies within a multidisciplinary approach should be addressed in future, well-sized and long-term studies.

Examination of night eating and loss-of-control eating following bariatric surgery

PURPOSE

Post-operative loss-of-control (LOC)-eating is a negative prognostic indicator for long-term outcomes following bariatric surgery. Emerging research suggests that night eating might also be associated with poorer post-operative outcomes. This study examined the co-occurrence and clinical features of night eating in patients with LOC-eating following bariatric surgery.

METHODS

Participants were 131 adults who sought treatment for eating/weight concerns 6 months following sleeve gastrectomy. The Eating Disorder Examination (EDE) interview (Bariatric-Surgery-Version) assessed LOC-eating, regular night eating (at least weekly), and eating-disorder psychopathology. Participants completed the Night Eating Questionnaire (NEQ), Beck Depression Inventory (BDI-II), and the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Approximately, 15% met screening criteria for night-eating syndrome based on the NEQ. Greater NEQ scores were associated significantly with race, lower percent total weight loss (%TWL), and greater EDE, BDI-II, and PSQI scores. Similar results were observed when comparing groups with regular night eating (21.4%) versus without (78.6%); adjusting for race and %TWL revealed similar findings.

DISCUSSION

In post-bariatric patients with LOC-eating, 15% likely had night-eating syndrome and 21.4% engaged in regular night-eating behavior. The co-occurrence of LOC-eating and regular night eating following sleeve gastrectomy may represent a more severe subgroup with elevated psychopathology, poorer sleep and %TWL.

LEVEL OF EVIDENCE

Level III, evidence obtained from well-designed cohort or case-control analytic studies.

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

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

Night Eating Syndrome and Its Relationship with Emotional Eating, Sleep Quality and Nutritional Status Among Adolescents' Boys

Current study was aimed to evaluate the relationship between emotional eating and night eating syndrome (NES) with sleep quality among adolescents in Tabriz-Iran. The current study was conducted among eighty adolescent boys aged 12-16 years old from Tabriz-Iran. Night eating syndrome and Emotional eating were measured by validated specific questionnaires. Pittsburgh Sleep Quality Index questionnaire (PSQI) was used for assessment of sleep quality. Emotional and very emotional eaters had significantly higher protein and fat intake. Among components of PSQI, subjective sleep quality, sleep disturbances and daytime dysfunction scores among emotional and very emotional eaters were significantly higher. Moreover, adolescents with NES, had higher PSQI score and lower carbohydrate intake; whereas, intake of fat among NES group was significantly higher (P < 0.05). Our results indicated poor sleep quality and higher dietary fat intake among adolescents with emotional eating disorder and NES. Therefore, it is necessary to consider healthy nutritional pattern including low fat intake in prevention of developing emotional eating and NES among adolescents.

Night eating syndrome: a psychiatric disease, a sleep disorder, a delayed circadian eating rhythm, and/or a metabolic condition?

Introduction: Night Eating Syndrome (NES) refers to an abnormal eating behavior which presents as evening hyperphagia consuming >25% calorie intake and/or nocturnal awaking with food ingestion which occurs ≥2 times per week. Although the syndrome has been described more than seven decades ago, the literature has been growing slowly on its etiology, diagnosis, and treatment. Areas covered: The proposed treatment options for NES are all at a case-study level. Moreover, our understanding of its etiology, comorbidities, and diagnosis is still premature. We performed a literature review in Medline/PubMed to identify all the studies proposing a management plan for NES and summarized all the existing data on its diagnosis and treatment. Expert opinion: To date, none of the proposed treatment options for NES have been promising and long-term data on its efficacy is lacking. The slow growth of evidence on this debilitating but underreported condition may be due to unawareness among clinicians, under-reporting by patients, and unrecognized diagnostic criteria. Objective screening of symptoms during office visits especially for patients at a high-risk for NES will identify more patients suffering from the syndrome.

Disordered Eating Among Individuals with Excess Weight: a Review of Recent Research

PURPOSE OF REVIEW

The purpose of this review was to examine different forms of disordered eating among individuals with excess weight, including their rates, correlates, and psychosocial treatments.

RECENT FINDINGS

Binge eating/binge eating disorder, loss of control eating, emotional eating, and food addiction are all fairly prevalent among individuals with excess weight. They appear to share many of the same correlates, including broader eating disorder psychopathology, body/shape/weight concerns, depression, anxiety, and low self-esteem. Behavioral, cognitive-behavioral, and third-wave (e.g., acceptance, mindfulness) therapies appear effective in improving binge eating, loss of control eating, emotional eating, associated features (e.g., weight and shape concerns), and psychological distress (e.g., depression). Certain forms of disordered eating are elevated among individuals with excess weight, and psychosocial interventions have been found effective in improving symptomatology. Empirical research examining the efficacy of treatments for food addiction is lacking, and greatly needed given both its rate and controversy.

Links between the circadian rhythm, obesity and the microbiome

Obesity is linked to a wide range of serious illnesses. In addition to the important impact on the health of the individual, obesity also has a substantial impact on the economy. Disruption of physiological day-night cycles could contribute to the increased incidence of obesity. According to the American National Sleep Federation, the percentage of the people who reported a sleep duration of six hours or less increased from 12 to 37 % over ten years. Insufficient sleep leads not only to an increase of the total calorie intake but changes the meal preference in favor of palatable foods and meals with high carbohydrate content. A decrease of leptin and increase of ghrelin levels caused by sleep deficiency can also play a role. In addition to the higher caloric intake, the timing of food consumption should be taken into account. The same meal eaten during the night versus the day is associated with increased postprandial glucose and triglyceride levels. The gut microbiome has also been recently understood as an endocrine system, with links between the gut microbiome and circadian rhythm changes possibly influencing increased obesity.

The relationship among breakfast time, morningness-eveningness preference and body mass index in Type 2 diabetes

AIMS

Obesity is prevalent and related to poor outcomes in Type 2 diabetes. Evening preference and late meal times have been shown to be associated with obesity, but data are lacking in people with Type 2 diabetes. This study examined the relationship among meal timing, morningness-eveningness preference and BMI in Type 2 diabetes, using a mediation analysis.

METHODS

Some 210 non-shift workers with Type 2 diabetes participated in the study. Morningness-eveningness preference was assessed using a standard questionnaire, the Composite Scale of Morningness (CSM). Meal timing and daily calorie intake were obtained from 1-day food recall. A mediation analysis adjusting for relevant covariables was performed to explore whether morningness-eveningness had a direct effect on BMI, or whether the effect was mediated through the intermediate variable of meal timing.

RESULTS

Mean BMI was 28.4 ± 4.8 kg/m² . A higher BMI was associated with greater evening preference (P = 0.019), and non-significantly associated with late breakfast time (P = 0.053). BMI was not associated with other mealtimes or calorie intake. In addition, evening preference was associated with late breakfast time (P < 0.001). Mediation analysis revealed that breakfast time mediated the association between morningness-eveningness and BMI, i.e. morning preference (CSM ≥ 45) was associated with earlier breakfast time, and lower BMI by 0.37 kg/m² [coefficient = -0.365, 95% confidence intervals (CI): -0.877, -0.066), whereas the direct relationship between BMI and morningness-eveningness was non-significant.

CONCLUSIONS

Late breakfast time mediated the relationship between morningness-eveningness preference and BMI. These results suggest that circadian preference and meal timing are novel and possibly modifiable risk factors for obesity in Type 2 diabetes.

Association of depression with body mass index classification, metabolic disease, and lifestyle: A web-based survey involving 11,876 Japanese people

Body mass index (BMI) and lifestyle-related physical illnesses have been implicated in the pathology of depression. We aimed to investigate the association of depression wih BMI classification (i.e., underweight, normal, overweight, and obese), metabolic disease, and lifestyle using a web-based survey in a large cohort. Participants were 1000 individuals who have had depression (mean age: 41.4 ± 12.3 years, 501 men) and 10,876 population-based controls (45.1 ± 13.6 years, 5691 men). The six-item Kessler scale (K6) test was used as a psychological distress scale. Compared to in the controls, obesity and hyperlipidemia were more common and frequency of a snack or night meal consumption was higher, whereas frequencies of breakfast consumption and vigorous and moderate physical activities were lower in the patients. K6 test scores were higher for underweight or obese people compared to normal or overweight people. A logistic regression analysis showed that the K6 test cut-off score was positively associated with being underweight, hyperlipidemia, and the frequency of a snack or night meal consumption, whereas it was negatively associated with the frequency of breakfast consumption in the patients. Logistic regression analyses showed that self-reported depression was positively associated with metabolic diseases and the frequency of a snack or night meal consumption, whereas it was negatively associated with the frequency of breakfast consumption. The observed associations of depression with BMI classification, metabolic disease, and lifestyle suggest that lifestyle and related physical conditions are involved in at least a portion of depressive disorders.

Night eating model shows time-specific depression-like behavior in the forced swimming test

The circadian clock system is associated with feeding and mood. Patients with night eating syndrome (NES) delay their eating rhythm and their mood declines during the evening and night, manifesting as time-specific depression. Therefore, we hypothesized that the NES feeding pattern might cause time-specific depression. We established new NES model by restricted feeding with high-fat diet during the inactive period under normal-fat diet ad libitum. The FST (forced swimming test) immobility time in the NES model group was prolonged only after lights-on, corresponding to evening and early night for humans. We examined the effect of the NES feeding pattern on peripheral clocks using PER2::LUCIFERASE knock-in mice and an in vivo monitoring system. Caloric intake during the inactive period would shift the peripheral clock, and might be an important factor in causing the time-specific depression-like behavior. In the NES model group, synthesis of serotonin and norepinephrine were increased, but utilization and metabolism of these monoamines were decreased under stress. Desipramine shortened some mice’s FST immobility time in the NES model group. The present study suggests that the NES feeding pattern causes phase shift of peripheral clocks and malfunction of the monoamine system, which may contribute to the development of time-specific depression.

Disordered eating and obesity: associations between binge-eating disorder, night-eating syndrome, and weight-related comorbidities

Binge-eating disorder (BED) and night-eating syndrome (NES) are two forms of disordered eating associated with overweight and obesity. While these disorders also occur in nonobese persons, they seem to be associated with weight gain over time and higher risk of diabetes and other metabolic dysfunction. BED and NES are also associated with higher risk of psychopathology, including mood, anxiety, and sleep problems, than those of similar weight status without disordered eating. Treatments are available, including cognitive behavior therapy (CBT), interpersonal psychotherapy, lisdexamfetamine, and selective serotonin reuptake inhibitors (SSRIs) for BED; and CBT, SSRIs, progressive muscle relaxation, and bright light therapy for NES.

Deconstructing "Atypical" Eating Disorders: an Overview of Emerging Eating Disorder Phenotypes

Recent changes to the diagnostic framework of eating disorders (ED's) in DSM-5 were introduced to reduce the large preponderance of cases falling within the residual and undifferentiated category. However, current reports continue to illustrate overrepresentation of cases in this residual category, suggesting that clinical reality comprises more diverse ED psychopathology than is accounted for in the current diagnostic spectrum. However, with emerging evidence preliminarily delineating several additional distinct phenotypes, we aim to provide a narrative overview of emerging ED phenotypes which (i) are not currently located as a specific diagnostic category in diagnostic criteria for ED's, (ii) centrally feature ED psychopathology, and (iii) have emerging empirical evidence suggesting the distinct nature of the syndrome. A greater awareness of these emerging phenotypes will likely facilitate accurate diagnostic practice and may also serve to facilitate further empirical efforts.