Rigor and reproducibility via laboratory studies of eating behavior: A focused update and conceptual review

The role of sexual assault history and PTSD in responses to food intake among women with bulimic-spectrum eating disorders

Sexual abuse or assault (SA) history is associated with eating disorder severity and psychiatric comorbidity, including post-traumatic stress disorder (PTSD). Beyond persistent alterations in mood and cognitions characterizing PTSD, PTSD due to SA may contribute to greater increases in negative affect and body image concerns following food intake in bulimic syndromes (BN-S). To test this, participants (n = 172) with BN-S who reported PTSD due to SA, PTSD due to other forms of trauma, or neither completed clinical interviews and momentary reports of negative affect and shape/weight preoccupation before and after food intake. Participants with PTSD, regardless of trauma source, reported higher purging frequency whereas PTSD due to SA was associated with more frequent loss of control eating. For one task, changes in negative affect following food intake differed across the three groups. Negative affect decreased significantly in participants with PTSD without SA whereas nonsignificant increases were observed in those with PTSD with SA. Results of the present study suggest that source of trauma in PTSD may impact likelihood that eating regulates affect and provide insight into ways current treatments may be adapted to better target purging in BN-S comorbid with PTSD.

Eating behavior in atypical anorexia nervosa

OBJECTIVE

Atypical anorexia nervosa (AN) has been increasingly identified in the community and in clinical settings. Initial studies indicate that psychological symptoms are similar or more severe among patients with atypical AN, as compared with AN. This study examined whether eating behavior differed among patients with AN (n = 98), patients with atypical AN (n = 18), and healthy controls (HC, n = 75).

METHOD

Adults and adolescents chose what to eat from a standardized, laboratory-based multi-item meal. Total intake, macronutrient composition, diet variety, and energy density were compared between groups.

RESULTS

Both AN and atypical AN severely restricted caloric intake as compared with HC (431 ± 396 kcal and 340 ± 338 kcal vs. 879 ± 350 kcal, F2,188 = 35.4, p < .001). Individuals with AN and atypical AN did not differ in the mean intake of total calories or percentage of calories from fat (15.2 ± 25.2% vs. 11.5 ± 16.9%).

DISCUSSION

This study demonstrates that individuals with atypical AN are at least as restrictive in their food intake as individuals with AN, and the restriction of dietary fat is particularly notable. Examination of eating behavior in a larger sample would be useful to replicate these findings. The current study highlights the need to understand maladaptive eating behavior in atypical AN in order to develop appropriate treatment recommendations.

PUBLIC SIGNIFICANCE

Atypical anorexia nervosa is emerging as a prevalent eating disorder in community and clinical populations. The findings that patients with atypical anorexia nervosa limit calorie and fat intake in a pattern similar to that of patients with anorexia nervosa highlights the need for research to identify appropriate treatment strategies for normalization of eating patterns.

Reduced dorsal fronto-striatal connectivity at rest in anorexia nervosa

BACKGROUND

Anorexia nervosa (AN) is a serious psychiatric illness that remains difficult to treat. Elucidating the neural mechanisms of AN is necessary to identify novel treatment targets and improve outcomes. A growing body of literature points to a role for dorsal fronto-striatal circuitry in the pathophysiology of AN, with increasing evidence of abnormal task-based fMRI activation within this network among patients with AN. Whether these abnormalities are present at rest and reflect fundamental differences in brain organization is unclear.

METHODS

The current study combined resting-state fMRI data from patients with AN (n = 89) and healthy controls (HC; n = 92) across four studies, removing site effects using ComBat harmonization. First, the a priori hypothesis that dorsal fronto-striatal connectivity strength - specifically between the anterior caudate and dlPFC - differed between patients and HC was tested using seed-based functional connectivity analysis with small-volume correction. To assess specificity of effects, exploratory analyses examined anterior caudate whole-brain connectivity, amplitude of low-frequency fluctuations (ALFF), and node centrality.

RESULTS

Compared to HC, patients showed significantly reduced right, but not left, anterior caudate-dlPFC connectivity (p = 0.002) in small-volume corrected analyses. Whole-brain analyses also identified reduced connectivity between the right anterior caudate and left superior frontal and middle frontal gyri (p = 0.028) and increased connectivity between the right anterior caudate and right occipital cortex (p = 0.038). No group differences were found in analyses of anterior caudate ALFF and node centrality.

CONCLUSIONS

Decreased coupling of dorsal fronto-striatal regions indicates that circuit-based abnormalities persist at rest and suggests this network may be a potential treatment target.

The buffet challenge: a behavioral assessment of eating behavior in adolescents with an eating disorder

OBJECTIVE

Eating disorders are characterized by disturbances in nutritional intake and abnormal mealtime behaviors. Laboratory eating paradigms offer a unique opportunity to accurately measure dietary intake and eating behaviors, however, these studies have predominantly occurred in adults. This paper describes the development and preliminary psychometric examination of the Buffet Challenge, a laboratory-based meal task for youths with an eating disorder.

METHOD

We recruited and assessed 56 participants as part of a randomized controlled trial of Family-Based Treatment for adolescents with anorexia nervosa. Adolescents completed the Buffet Challenge at baseline, midway through treatment (~ week 16 of a 6 months course), and end of treatment. Participants and their parents also reported eating disorder symptomatology and treatment related variables of interest were recorded.

RESULTS

All adolescents were willing to complete the Buffet Challenge at all time points, although one refused to give up their cellphone, and there were no significant adverse events recorded. Preliminary results are presented.

CONCLUSIONS

Our initial pilot of this task in adolescents with anorexia nervosa demonstrates its acceptability, although investigation of our hypotheses was hindered by significant missing data due to COVID-related research shutdowns. Future studies should replicate procedures in a larger sample to ensure analyses are adequately powered.

Examining trait-like factors as predictors of state-level responses to food intake in women with bulimia nervosa, purging disorder, and controls

OBJECTIVE

Theories suggest that elevated negative affect and weight/shape concerns explain both who is affected by bulimic symptoms as well as when bulimic symptoms occur, suggesting that individual differences predict within-subject differences. However, few studies have tested this theoretical premise.

METHOD

In the present study, participants (N = 119) diagnosed with bulimia nervosa (N = 57), purging disorder (N = 31), and non-eating disorder controls (N = 31) completed measures of negative affect and weight/shape concerns and later made momentary affect and weight/shape concerns ratings before and after an ad lib meal.

RESULTS

State negative affect and weight/shape concerns increased post-meal. No moderating effect of trait negative affect was observed for state affect. In contrast, between-subject differences in weight/shape concerns moderated within-subject increases in state weight/shape concerns. Diagnostic group did not account for this effect.

DISCUSSION

Findings point to viable treatment targets for disordered eating. Targeting elevated weight/shape concerns early in interventions could facilitate reductions in purging after food intake for bulimia nervosa and purging disorder.

PUBLIC SIGNIFICANCE

In the present study, individual differences in weight/shape concerns at baseline predicted greater increases in state weight/shape concerns following eating. These effects were maintained when considering possible differences related to presence and type of eating disorder. Results suggest that targeting weight/shape concerns earlier in treatment may be important for reducing maladaptive responses to eating across eating disorders.

Unequivocally large, but not enormous: An examination of the nutritional content of objective and subjective binge-eating episodes using ecological momentary assessment data

OBJECTIVE

This study compared the macronutrient profiles of subjective binge-eating episodes (SBEs), objective binge-eating episodes (OBEs), and typical eating episodes.

METHOD

Twenty-one adults with binge eating completed ecological momentary assessment of all eating episodes for 2 weeks, including detailed monitoring of food types and portions. Binge-eating episodes (N = 237) were coded as OBEs (n = 76) or SBEs (n = 161). Calories and macronutrients were computed using manufacturer information and USDA Food and Nutrient Database for Dietary Studies. Multilevel regression models compared the eating episode types on caloric and macronutrient content.

RESULTS

OBEs contained an average of 121.5 (95.1) g fat, 363.7 (289.1) g carbohydrates, 65.2 (38.2) g protein, 20.9 (16.4) g fiber, and 2856.2 (1869.2) calories. SBEs contained 31.6 (30.5) g fat, 76.5 (54.0) g carbohydrates, 20.5 (21.6) g protein, 5.3 (5.9) g fiber, and 695.1 (505.9) calories. Although OBEs contained significantly more calories and grams of all macronutrients than SBEs (p < .001), the macronutrient proportions of OBEs and SBEs did not differ. The proportions of carbohydrates (p = .005) and protein (p < .001) in SBEs significantly differed from typical eating episodes.

DISCUSSION

Our findings offer preliminary evidence that OBEs and SBEs are more comparable in macronutrient profile than typical eating episodes.

PUBLIC SIGNIFICANCE STATEMENT

The present study compared the calories and grams of macronutrients in objectively large binge-eating episodes, subjectively large binge-eating episodes, and typical meals and snacks. Results suggest that objectively and subjectively large binge-eating episodes demonstrate similar profiles of macronutrients, which are different from the macronutrient profile of meals and snacks. These results may help the eating disorder field better study the impact of subjectively large binge-eating episodes.

Examining the role of urgency in predicting binge size in bulimia nervosa

Greater binge size within bulimia nervosa is associated with elevated distress and impairment. Theoretical models posit that emotion dysregulation predicts binge eating, but little research has investigated the potential for dispositional traits that reflect difficulty in emotion regulation to predict binge size among women with bulimia nervosa. Research supports that negative urgency, the tendency to act rashly when feeling distressed, is associated with binge eating behavior among individuals with bulimia nervosa. Relatively fewer studies have explored associations between binge eating and positive urgency, the tendency to act rashly when feeling extreme positive affect. The urgency traits may predict greater binge size within bulimia nervosa. The current study sought to examine negative urgency and positive urgency as predictors of test meal intake in a sample of 50 women, n = 21 with bulimia nervosa and n = 29 healthy controls. Dispositional levels of positive urgency, negative urgency, positive affect, and negative affect were measured prior to a laboratory binge eating paradigm. Participants in the bulimia nervosa group scored higher on negative urgency, positive urgency, and negative affect than participants in the control group. Across participants, lower levels of negative affect were associated with greater test meal intake. Elevated levels of positive urgency predicted significantly greater test meal intake, but only for participants with bulimia nervosa. No other dispositional traits predicted test meal intake when the interaction of positive urgency and group was included in the model. Findings suggest positive urgency is an underappreciated, but potentially important, risk factor for greater binge size in bulimia nervosa.

Increases in shame following binge eating among women: Laboratory and longitudinal findings

This multi-method, two-study investigation tested the hypothesis that, controlling for guilt and negative affect, shame increases following binge eating. Support for this hypothesis constitutes the first step in testing the theory that shame mediates the link between binge eating and comorbid psychopathology. Study 1 employed a laboratory binge-eating paradigm in n = 51 women [21 with bulimia nervosa, 30 controls]. Study 2 employed a naturalistic test of prospective relationships among binge eating, shame, guilt, and negative affect in n = 302 college women over three months. In Study 1, women with bulimia nervosa reported increases in shame that were not explained by changes in guilt or negative affect, following laboratory binge eating, compared with controls. In Study 2, baseline binge eating predicted increased shame at follow-up independently of guilt and negative affect. Should shame prove to mediate the link between binge eating and comorbid disorders, interventions to reduce shame may be useful for those who binge.

Restrictive eating across a spectrum from healthy to unhealthy: behavioral and neural mechanisms

BACKGROUND

Restriction of food intake is a central feature of anorexia nervosa (AN) and other eating disorders, yet also occurs in the absence of psychopathology. The neural mechanisms of restrictive eating in health and disease are unclear.

METHODS

This study examined behavioral and neural mechanisms associated with restrictive eating among individuals with and without eating disorders. Dietary restriction was examined in four groups of women (n = 110): healthy controls, dieting healthy controls, patients with subthreshold (non-low weight) AN, and patients with AN. A Food Choice Task was administered during fMRI scanning to examine neural activation associated with food choices, and a laboratory meal was conducted.

RESULTS

Behavioral findings distinguished between healthy and ill participants. Healthy individuals, both dieting and non-dieting, chose significantly more high-fat foods than patients with AN or subthreshold AN. Among healthy individuals, choice was primarily influenced by tastiness, whereas, among both patient groups, healthiness played a larger role. Dorsal striatal activation associated with choice was most pronounced among individuals with AN and was significantly associated with selecting fewer high-fat choices in the task and lower caloric intake in the meal the following day.

CONCLUSIONS

A continuous spectrum of behavior was suggested by the increasing amount of weight loss across groups. Yet, data from this Food Choice Task with fMRI suggest there is a behavioral distinction between illness and health, and that the neural mechanisms underlying food choice in AN are distinct. These behavioral and neural mechanisms of restrictive eating may be useful targets for treatment development.

Measuring Ostracism-Induced Changes in Consumption of Palatable Food: Feasibility of a Novel Behavioral Task

Purpose

Ostracism is a highly aversive interpersonal experience. Previous research suggests that it can increase consumption of highly palatable food in some individuals, but decrease it in others. Thus, we developed the Cyberball-Milkshake Task (CMT), to facilitate research investigating individual differences in ostracism's effects on consumption of highly palatable food. We present data on feasibility for the CMT in a sample of young adult women.

Materials and Methods

Participants were 22 women, 18-30 years old, reporting very low or very high levels of emotional eating at screening. Participants performed the CMT, which consisted of 12 trials. Each trial included: playing a round of Cyberball (a computerized game of catch with fictitious "other participants" programmed to either include or exclude the participant); viewing a chocolate image; and then consuming a participant-determined amount of milkshake. Participants subsequently played an additional inclusion and exclusion round of Cyberball, each immediately followed by questionnaires assessing current mood and recent Cyberball experience.

Results

Cyberball exclusion (vs. inclusion) was associated with large, significant increases in reported ostracism and threats to self-esteem; exclusion's effects on affect were in the expected direction (e.g., increased negative affect), but generally small and non-significant. Milkshake intake was measurable for 95% of participants, on 96% of trials. Intake decreased quadratically across trials, with a steep negative slope for low trial numbers that decreased to the point of being flat for the highest trial numbers.

Discussion

The CMT is a generally feasible approach to investigating ostracism's effects on consumption of highly palatable food. The feasibility (and validity) of the CMT may benefit from modification (e.g., fewer trials and longer rounds of Cyberball). Future research should examine whether performance on a modified version of the CMT predicts real-world behavior in a larger sample.

The Universal Eating Monitor (UEM): objective assessment of food intake behavior in the laboratory setting

The Universal Eating Monitor was a term used to describe a device used in a laboratory setting that enabled investigators to measure, with the same instrument, the rate of eating either solids or liquids, hence the term “universal”. It consisted of an electronic balance placed in a false panel under a table cloth on which could be placed a food reservoir that contained either solid or liquefied food. The device was created in order to determine whether rates of eating differed in pattern between solid and liquid foods. An acceptable mixture of foods of identical composition that could be served as either solid or blended as a liquid was used to test the hypothesis that eating rate and intake were affected by physical composition. A best-fitting mathematical function (intake was quadratic function of time, with coefficients varying among foods used and experimental conditions), quantified intake rates. The device was used to test a variety of mechanisms underlying food intake control. Eating rates were linear when solid foods were used, but negatively accelerated with liquids. Overall, intake did not differ between solid and liquefied food of identical composition. Satiation on a calorie for calorie basis was different among foods, but physical composition interacted with energy density. Hormones and gastric distension were strong influences on food intake and rate of eating. Individuals with bulimia nervosa and binge eating disorder ate more than individuals without these disturbances. Intake in social and individual contexts was identical, but the rate of eating was slower when two individuals dined together. The eating monitor has been a useful instrument for elucidating controls of food intake and describing eating pathology.

Comparison of ad libitum snack consumption and acquisition between adolescents living with food security and food insecurity: A stage 1 registered report

OBJECTIVE

Approximately 11% of the U.S. population experiences food insecurity (FI; insufficient access to healthy food due to financial constraints). FI is associated with detrimental health outcomes, including the development of eating disorders (EDs). However, additional studies are needed, particularly in adolescence when EDs are likely to emerge. The current study will utilize an experimental ad libitum snack paradigm to investigate snack consumption, acquisition (i.e., taking snacks home), and associated disordered eating behaviors among racially, ethnically, and financially diverse adolescents living with FI and food security (FS).

METHOD

Sixty-four adolescents will be recruited and randomized into one of two conditions: prior knowledge condition (i.e., participants will know prior to snacking that they can take any remaining food home) and no prior knowledge condition (i.e., participants will not know ahead of time that they can take snacks home).

RESULTS

We expect youth with FI to show increased eating and acquisition behaviors compared to youth with FS across both conditions.

DISCUSSION

This study, utilizing a novel experimental design, is an important step in understanding how FI impacts adolescent eating behaviors among youth from marginalized backgrounds, who have historically been excluded from research.

Open science practices for eating disorders research

This editorial seeks to encourage the increased application of three open science practices in eating disorders research: Preregistration, Registered Reports, and the sharing of materials, data, and code. For each of these practices, we introduce updated International Journal of Eating Disorders author and reviewer guidance. Updates include the introduction of open science badges; specific instructions about how to improve transparency; and the introduction of Registered Reports of systematic or meta-analytical reviews. The editorial also seeks to encourage the study of open science practices. Open science practices pose considerable time and other resource burdens. Therefore, research is needed to help determine the value of these added burdens and to identify efficient strategies for implementing open science practices.

Associations between mealtime anxiety and food intake in anorexia nervosa

OBJECTIVE

A salient disturbance in anorexia nervosa (AN) is the persistent restriction of food intake. Eating behavior in AN is thought to be influenced by anxiety. The current study probed associations between mealtime anxiety and food intake among individuals with AN and healthy comparison individuals (HC).

METHOD

Data were combined across three studies (total of 92 AN and 78 HC) for secondary data analysis. Participants completed a multiitem laboratory buffet meal and visual analogue scale assessments of pre-meal and post-meal anxiety. Linear regression models assessed the association between mealtime anxiety and calorie and fat intake at the meal, and whether associations differed by diagnostic group.

RESULTS

Among individuals with AN, pre-meal anxiety was significantly associated with reduced calorie intake and reduced consumption of calories from fat at the meal; these associations were not observed among HC. There was no evidence for an association between calorie/fat intake at the meal and post-meal anxiety in either group.

DISCUSSION

Treatments that target mealtime anxiety may improve eating and nourishment among individuals with AN. Interventions like exposure therapy that provide skills in overcoming mealtime anxiety might be enhanced by informing patients that post-meal anxiety is not related to intake.

Characterising binge eating over the course of a feasibility trial among individuals with binge eating disorder and bulimia nervosa

Binge eating disorder and bulimia nervosa are eating disorders that are characterized by recurrent binge eating episodes. The highly contextualized nature of binge eating makes naturalistic research a particularly suitable means of understanding the context within which binge eating occurs. The present study aimed to characterise binge eating days with regards to the frequency and probability of negative affect, food craving, meal skipping, and dietary restriction. In addition, it aimed to examine whether a combined intervention that targets the experience of 'loss of control' over eating can decrease these potential maintenance factors that often precede binge eating episodes. Seventy-eight participants with bulimia nervosa (N = 40) or binge eating disorder (n = 38), who were randomly allocated to a food-specific or general intervention combining inhibitory control training and implementation intentions, completed mood and food diaries over four weeks. Results suggest that negative affect and food craving were elevated on binge eating days, but that dietary restraint and meal skipping did not characterise binge eating days. Moreover, meal skipping, binge eating, restriction, and compensation decreased throughout the intervention period, while negative affect and food craving did not. This suggests that some interventions may successfully reduce binge eating frequency without necessarily decreasing negative affect or food craving, thus pointing to the different routes to targeting binge eating and providing implications for future interventions.

Alternative Frameworks for Advancing the Study of Eating Disorders

Eating disorders are life-interrupting psychiatric conditions with high morbidity and mortality, yet the basic mechanisms underlying these conditions are understudied compared with other psychiatric disorders. In this opinion, we suggest that recent knowledge gleaned from genomic and neuroimaging investigations of eating disorders in humans presents a rich opportunity to sharpen animal models of eating disorders and to identify neural mechanisms that contribute to the risk and maintenance of these conditions. Our article reflects the state of the science, with a primary focus on anorexia nervosa (AN) and binge-eating behavior, and encourages further study of all conditions categorized under feeding and eating disorders.

Habits are stronger with longer duration of illness and greater severity in anorexia nervosa

OBJECTIVE

The aim of this study was to examine the relationship between habit strength and clinical features of anorexia nervosa (AN). Habit strength, separate from intention, relates to the persistence of behavior, and is measured by the Self-Report Habit Index (SRHI). We hypothesized that habit strength would be greater among individuals with AN than healthy controls (HC) and that habit strength would be associated with duration and severity of illness.

METHOD

Participants were 116 women with AN (n = 69) and HC (n = 47) who completed the SRHI, the Eating Disorder Examination-Questionnaire (EDE-Q), and a multi-item laboratory meal. The SRHI assessed four domains and these subscales were averaged for the total score.

RESULTS

Individuals with AN demonstrated significantly greater habit strength than HC in the total score (t₁₁₄ = 7.00, p < .01), and within each domain (restrictive eating, compensatory behavior, delay of eating, and rituals). Total SRHI score was significantly associated with EDE-Q scores for both AN and HC groups (r_AN = .59, p_AN = <.001; r_HC = .32, p_HC = .030). Among patients, there was a significant association between SRHI and duration of illness (r = .38, p = .001). There was no significant association between SRHI and caloric intake (r_AN = -.20, p_AN = .10; r_HC = -.25, p_HC = .09).

DISCUSSION

Habit strength was related to chronicity and severity of AN, suggesting that habit formation may play an important role in illness. These data suggest avenues for mechanism research and treatment development.

Emotion regulation and emotional eating in anorexia nervosa and bulimia nervosa

Individuals with anorexia nervosa (AN) and bulimia nervosa (BN) show emotion regulation deficits. While individuals with BN use binge eating to regulate negative affect, individuals with restricting-type AN may use self-starvation for this purpose. The current study examined the emotion regulatory function of over- and undereating in response to different emotional states in women with restrictive AN (n = 54), BN (n = 47), and women without eating disorders (n = 68). Participants completed self-report measures assessing the use of emotion regulation strategies and emotional eating. Both patient groups reported using more dysfunctional and less functional emotion regulation strategies than controls. The BN group reported eating more than usual in response to negative emotions but less than usual in response to positive emotions. In contrast, the AN group reported eating more than usual in response to positive emotions and less than usual in response to negative emotions. More dysfunctional emotion regulation related to eating less in response to negative emotions in the AN group. Less functional emotion regulation related to eating less when being happy in the BN group. The current study highlights the need to differentiate between different eating outcomes and different emotional states when examining emotion effects on food intake.

The FTO Gene and Measured Food Intake in 5- to 10-Year-Old Children Without Obesity

OBJECTIVE

Genetic variation in the first intron of FTO (e.g., single-nucleotide polymorphism [SNP] rs9939609) is strongly associated with adiposity. This effect is thought to be mediated (at least in part) via increasing caloric intake, although the precise molecular genetic mechanisms are not fully understood. Prior pediatric studies of FTO have included youth with overweight and obesity; however, they have not informed whether a genotypic effect on ingestive behavior is present prior to obesity onset. Therefore, this study investigated the association between FTO and caloric intake in children aged 5 to 10 years without obesity (adiposity ≤ 95th percentile).

METHODS

A total of 122 children were genotyped for rs9939609 and ate ad libitum from a laboratory lunch buffet following a standardized breakfast. Linear regressions, adjusting for body mass, were used to examine the association between FTO "dose" (number of copies of SNP rs9939609) and intake variables.

RESULTS

There was a significant association between FTO and total intake. Each risk allele predicted an additional 64 calories, accounting for 3% of the variance. There were no associations between FTO and macronutrient preference, energy density, or diet variety. Results were influenced by race.

CONCLUSIONS

Results corroborate and extend prior work by showing a dose-dependent effect on food intake in children without obesity.

Fat preference and fat intake in individuals with and without anorexia nervosa

Fat restriction is a characteristic eating behavior among individuals with anorexia nervosa (AN), and laboratory meal studies demonstrate restricted fat intake among low-weight patients. The Geiselman Food Preference Questionnaire-I^© (FPQ) is a validated self-report measure that yields a fat preference score (FPS). Prior research reported that patients with AN had a significantly lower FPS than did healthy control (HC) participants. The goal of the current study was to compare self-reported fat preference (FPS) to fat intake (multi-item meal (MIM) study) in low-weight ANs and HCs. Specific aims were 1) to determine if the FPS differed between ANs and HCs; 2) to determine if fat and energy intakes differed between ANs and HCs; and 3) to determine if the FPS was associated with fat and energy intakes in ANs and HCs. Forty-four female AN inpatients and 48 female HCs completed the FPQ and participated in a MIM study. Compared to HCs, ANs consumed less energy (469.1 ± 397.7 vs. 856.4 ± 346.8 kcal, p < 0.001), less fat (16.4 ± 20.4 vs. 36.7 ± 18.9 g, p < 0.001), and a smaller percentage of calories from fat (22.9 ± 13.8 vs. 36.6 ± 8.0%, p < 0.001) at the MIM. Compared to HCs, ANs also had a lower FPS (79.7 ± 27.4 vs. 102.3 ± 18.9, p < 0.001). The FPS was significantly and positively correlated with caloric intake (r = 0.481, p < 0.01), total fat (r = 0.453, p < 0.01), and the percentage of calories from fat (r = 0.37, p < 0.05) in ANs as well as in HCs (kcal: r = 0.583, p < 0.001; fat: r = 0.621, p < 0.001; % fat kcal: r = 0.601, p < 0.001). The FPS is related to objective measures of energy and fat intake in patients with AN as well as in healthy individuals.

Relationship between three factor eating questionnaire-restraint subscale and food intake

OBJECTIVE

Dietary restraint refers to an individual's intention to restrict food intake, measured via self-report questionnaires, whereas dietary restriction refers to actual reduction in caloric intake. The aim of this research was to investigate the association between dietary restraint scales and actual caloric restriction.

METHOD

Data were collected from six previously published or two ongoing eating behavior studies in which participants (n = 183) completed the Three Factor Eating Questionnaire (TFEQ) and Eating Disorders Examination Questionnaire (EDE-Q) and participated in a laboratory-based research lunch meal. Participants were individuals with anorexia nervosa (AN), bulimia nervosa (BN), and healthy controls (HC). The primary analysis was the association between TFEQ Restraint subscale and caloric intake in the meal.

RESULTS

There was a significant negative correlation between total caloric intake and TFEQ Restraint scores (r = -.60, p < .001) and EDE-Q Restraint scores (r = -.54, p < .001). For TFEQ Restraint score, this relationship was significant within each diagnostic group (HC: r = -.32, p = .007; AN: r = -.38, p < .001; BN: r = -.43, p = .02).

DISCUSSION

These results suggest that the TFEQ Restraint scale is a useful measure of dietary restriction, especially among individuals with eating disorders.