Eating Behaviors 14 (2013) 472–475
Contents lists available at ScienceDirect
Eating Behaviors
Cravings and food consumption in binge eating disorder Longena Ng ⁎, Caroline Davis Department of Psychology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
a r t i c l e
i n f o
Article history: Received 5 April 2013 Accepted 14 August 2013 Available online 23 August 2013 Keywords: Binge Eating Disorder Food Cravings Questionnaire Food consumption
a b s t r a c t The purpose of this study was to extend existing work that examines the role of cravings in Binge Eating Disorder (BED). The current study uses a case–control design to establish a relationship between cravings and food exposure, and between cravings and food consumption in individuals diagnosed with BED. Twenty-nine females with BED, 40 obese controls, and 50 normal-weight controls were first presented with a neutral cue and completed a food-craving measure. They were then presented with their favourite snack food and completed the craving measure again, after which they were allowed to consume the food. The BED group had significantly higher scores for pre- and post-craving measures, and consumed more food compared to the controls. There was, however, no significant interaction between group and craving scores. Results also showed a positive correlation between food consumption and cravings scores both before and after food exposure for individuals with BED. The findings suggest that the level of cravings prior to food exposure may be sufficient to predict overeating in BED and that treatment may want to target this as a defining feature that differentiates individuals with BED from those who do not binge eat. Crown Copyright © 2013 Published by Elsevier Ltd. All rights reserved.
1. Introduction The reduction in obesity is an important public health objective because of its association with high morbidity and mortality (Centre for Disease Control and Prevention, 2011). One contributor to the rising obesity rates is compulsive overeating — a hallmark criterion for Binge Eating Disorder (BED). To date, however, effective treatments for BED are generally lacking, in part, due to our incomplete understanding of the antecedents to binge episodes (Hudson et al., 2006; Temple et al., 2009). Some established binge-eating triggers include boredom, stress, fatigue, and low mood (Engelberg, Steiger, Gauvin, & Wonderlich, 2007; Laessle & Schulz, 2009; Redlin, Miltenberger, Crosby, Wolff, & Stickney, 2002). Food cravings have also been cited as a precipitant to binge episodes (Greeno, Wing, & Shiffan, 2000; Jansen, 1998). Appetite ratings and desire for food are typically measured through self-report — and believed to be the better assessment tools as they display stronger cue-specificity (Carter & Tiffany, 1999) — although physiological measures, such as heart rate and skin temperature, have also served as proxy indicators (Nederkoorn, Smulders, & Jansen, 2000). Studies have shown that those with eating disturbances report higher levels of cravings and food intake when exposed to a food cue compared to normal eaters (Sobik, Hutchison, & Craighead, 2005; Staiger, Dawe, & McCarthy, 2000). Currently only three studies have examined cravings in BED, showing that binge-eaters report higher levels of hunger and cravings than those who do not binge eat (Greeno et al., 2000; Jarosz, Dobal, ⁎ Corresponding author at: Centre for Addiction and Mental Health, 455 Spadina Avenue, Suite 200, Toronto, ON M5S 2G8, Canada. Tel.: +1 416 535 8501x77758. E-mail address: [email protected] (L. Ng).
Wilson, & Schram, 2007; Karhunen, Lappalianen, Tammela, Turpeinen, & Uusitupa, 1997). Some of the limitations of these studies were small sample sizes, the use of non-validated craving measures, and inclusion of those with BED and bulimia nervosa in the same group. The primary purpose of this study was to address the limitations of existing work on cravings in BED. To our knowledge, the current study is the first to compare women diagnosed with BED according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR; American Psychiatric Association, 2000) with appropriate control groups on food intake and cravings by using a well-validated multiitem craving scale. This study also assessed relationships between food exposure, food consumption, and cravings. Both normal-weight and weight-matched controls were used in order to ensure that the findings were attributable to the underlying eating pathology and not to other factors. Individuals with BED generally have a higher BMI than average; hence, it was particularly important to ensure that the results were not merely a facet of elevated weight (Greeno et al., 2000; Wilfley et al., 2002). It was hypothesized that there would be a significant interaction between time (cravings before and after food exposure) and group as well as main effects for time and group. Specifically, it was anticipated that BED participants would have higher craving scores compared to the control groups and all participants would have higher craving scores after food exposure than before exposure. It was also expected that individuals with BED would consume a significantly greater proportion of food than the controls, and that this would be independent of selfreported hunger (e.g., self-reported hunger ratings would not differ between the groups). Finally, it was predicted that cravings scores after presentation of the craved food would be positively correlated with percentage of food consumed for all participant groups.
1471-0153/$ – see front matter. Crown Copyright © 2013 Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.eatbeh.2013.08.011
L. Ng, C. Davis / Eating Behaviors 14 (2013) 472–475
473
2. Methods
2.3. Procedure
2.1. Participants
Potential participants were contacted by telephone and reported their weight and height to determine a provisional BMI for group assignment. Once deemed eligible, participants were asked about their most preferred snack food. Typical foods included chocolate, chips, and candy; no healthy foods such as apples or carrot sticks were requested. They were also told to consume a normal meal two hours prior to the study. On the day of testing, the SCID-I/P interview was administered to determine if the exclusion criteria were met. When appropriate, they were asked questions from the DSM-IV-TR and the EDE to determine a diagnosis of BED and the frequency of binge episodes. Next, they rated their current degree of hunger. Participants were then asked to look at a pencil (the control cue) prior to completing the FCQ-S, which instructed them to rate their cravings for their favourite snack food. Following these baseline measures, participants were given their selected snack food (which had been purchased prior to the testing session), after which they completed the FCQ-S again. At this point, participants were left alone for 15 min to complete some filler questionnaires. During that time participants were told they could consume the snack if they wished. At the end of the study, the snack was weighed if any remained. Participants were debriefed and paid a small stipend for their time and travel expenses.
Participants were pre-menopausal women between 25 and 50 years old recruited from advertisements placed at universities, hospitals, newspapers and online sites such as Craigslist. There were 29 obese participants with BED, 40 obese controls and 50 normal-weight controls. The mean monthly frequency of binge eating episodes in the BED group was 8.7. This study was approved by the York University ethics committee and was performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki. Exclusion criteria included current pregnancy (or a birth within the last 12 months), history of substance disorder, psychotic disorder, or currently participating in a weight-loss program or diet. The presence of any disordered eating behaviours, including binge-eating, was an additional exclusion criteria for the control groups. 2.2. Materials 2.2.1. Structured Clinical Interview for the DSM-IV-TR Axis I Disorders, Research Version, Patient Edition The Structured Clinical Interview for the DSM-IV-TR Axis I Disorders, Research Version, Patient Edition (SCID-I/P; First, Spitzer, Gibbon, & Williams, 2002) was used to screen for the Axis I disorders discussed in the exclusion criteria. Criteria found in Appendix B of the DSM-IVTR were used to diagnose BED.
2.2.2. Eating Disorder Examination Selected items from the Eating Disorder Examination (EDE; Fairburn & Cooper, 1993) were used to provide information about binge episodes (e.g., frequency). The EDE has shown good inter-rater reliability (r N .95) and test–retest reliability (r N .70) in assessing binge episodes (Grilo, Masheb, Lozano-Blanco, & Barry, 2004; Wilfley et al., 2002). 2.2.3. Body Mass Index Body Mass Index (BMI) [weight (kilogram)/height (metre)2] was calculated from height and weight measured with participants wearing light indoor clothing and standing in stocking feet. 2.2.4. Current hunger A 100 mm visual analogue line was used to measure self-reported hunger with 0 indicating “no hunger at all”, and 100 mm indicating the “most hunger imaginable”. 2.2.5. Food consumption The proportion of food consumed was calculated by dividing weight (grams) of the un-finished food after the exposure from the baseline weight of the food; this was then subtracted from 1. 2.2.6. Food Cravings Questionnaire-State The Food Cravings Questionnaire-State (FCQ-S; Cepeda-Benito, Gleaves, Williams, & Erath, 2000) is a 15-item self-report state measure of food cravings. It comprises five subscales which measure a desire to eat, reinforcement and relief from negative affect states after eating, lack of control, and craving as a physiological state. The total score was used to measure overall craving. It has shown high internal consistency in obese and overweight subjects (α = .88; Vander Wal, Johnston, & Nikhil, 2007), and in patients with eating disorders (α = .69 to .92 for the subscales; Moreno, Rodriguez, Fernandez, Tamez, & Cepeda-Benito, 2008). The Cronbach's α coefficient in this study was .91.
3. Results 3.1. Descriptive statistics There were no significant differences between the three groups in age (p = .11), marital status (p = .68), and ethnicity (p = .38). By design, the normal-weight controls had significantly lower BMIs than the obese controls and BED group, who did not differ from each other. See Table 1 for descriptive statistics. 3.2. Food cravings Repeated measures analysis of variance using Time (pre and post FCQ-S scores) as the within-subjects variable and Group as the between-subjects variable was used to assess cravings scores. There was a main effect of Group (F2, 116 = 8.55, p b .01) and Time (F1, 117 = 61.609, p b .001), but contrary to our hypothesis, the interaction was not statistically significant (p = .52). As expected, FCQ-S scores were higher after food exposure than before exposure. Tukey's post hoc analyses revealed that BED had significantly higher scores for pre and post FCQ-S compared to obese (p b .05) and normal-weight controls (p b .001), who did not differ from each other (see Fig. 1). 3.3. Food consumption Analysis of co-variance (ANCOVA) with Percentage of Food Consumed as the dependent variable, Group as the independent variable, and Hunger ratings as the covariate indicated a significant Group effect (F2, 116 = 2.66, p b 0.001). As hypothesized, the BED group consumed significantly greater proportions of food compared to the obese (p b .001) and normal-weight (p b .001) controls with no significant differences between the control groups (see Table 1). There
Table 1 Descriptive statistics (means and standard deviations) by group.
BMI Hunger (cm) Food consumed (%)
BED
Obese
Normal-weight
F
36.16(9.25)a 4.20(2.18) 57.38(.44)a
36.68(5.64)a 3.21(2.15) 16.67(.25)b
22.13(1.68)b 3.61(2.52) 22.79(2.66)b
89.09 b .001 1.645 .20 16.09 b .001
Note: a and b denote significance at p b .001.
p
474
L. Ng, C. Davis / Eating Behaviors 14 (2013) 472–475
Lapidoth, Ghaderi, & Norring, 2011), determining whether decreased cravings and consumption are related to subsequent decreases in psychopathology and other correlates (e.g., self-esteem, body image) is an important next step. One limitation is that there may have been another antecedent that was not being measured in this study that was correlated or causing food consumption in BED. Further, the current research focused solely on women due to the greater number of females diagnosed with BED than males (Tuschen-Caffier & Schlussel, 2005). Future studies should consider extending the research to males. This study showed that food cravings to non-salient food cues are correlated to over-eating in BED and that this is not a result of hunger or calorie deprivation. This is important as it suggests that the level of cravings prior to food exposure is one of the defining features that differentiate BED from non-binging individuals and it is these “anticipatory” cravings that may consequently precipitate a binge.
Fig. 1. Mean scores (standard error of the mean) on the Food Craving Questionnaire-State before and after food exposure by group.
was no significant difference between the groups on hunger ratings (see Table 1). 3.4. Craving and food consumption Also as hypothesized, there was a significant positive correlation between percentage of food consumed and FCQ-S scores after food exposure for BED participants (r = .596, p b .001), obese controls (r = .454, p b .01) and normal-weight controls (r = .300, p b .05). Interestingly, we found a significant correlation between food consumed and FCQ-S prior to food exposure for the BED group only (r = .518, p b .05). 4. Discussion The purpose of this study was to address the limitations of existing researching on cravings and food consumption in those with BED. Our hypotheses were supported to some degree. Compared to both controls, individuals with BED had significantly higher craving scores before and after food exposure, and consumed a significantly greater proportion of food. Contrary to our predictions the interaction between group and craving scores was not significant. As expected, food cues elicit cravings and cue-elicited cravings were correlated with food consumption in all groups; however, uncued cravings were correlated with consumption only in the BED group. This suggests that explicit food cues may not be necessary to precipitate binges in individuals with BED. It is possible that these “baseline” cravings represent the anticipatory effect of food since participants were asked about their favourite snack food during the screening and may have expected the food during the study. Therefore it appears that these less salient stimuli, or the anticipation of the food, may have been sufficient to predict consumption in BED. This is consistent with existing literature which suggests that individuals with BED display greater hedonic hunger (a subjective state that occurs in the absence of an energy deficit and is largely regulated by the palatability of food) than those who do not binge eat (Davis et al., 2009; Lowe & Butryn, 2007). Gaining an understanding of the antecedents to binge episodes will contribute to the design of clinical interventions. For instance, Kemps and Tiggemann (2007) found that olfactory and visual imagery of nonfood items decreased cravings, and using imagery to decrease the anticipatory cravings in BED may be effective in the subsequent prevention of a binge episode. Given that BED in obese individuals is associated with greater comorbid psychopathology and poorer overall health outcomes compared to non-binging obese individuals (de Man
Role of Funding Sources Funding for this study was provided by a minor research grant from York University's Faculty of Health and the SSHRC Small Grants Program. Neither funding source had a role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication.
Contributors Dr. Ng designed the study, conducted literature searches, collected the data, conducted the statistical analyses, and wrote the first draft of the manuscript. Dr. Davis contributed to the study design, statistical analyses, and revisions of the manuscript. Both authors contributed to and have approved the final manuscript.
Conflict of Interest Drs. Ng and Davis declare that they have no conflicts of interest.
References American Psychiatric Association (2000). Diagnostic and statistical manual (4th ed., Text Revision )Washington, D.C.: American Psychiatric Association. Carter, B.L., & Tiffany, S. T. (1999). A meta-analysis of cue-reactivity in addiction research. Addiction, 94, 327–340. Centre for Disease Control and Prevention (2011). Obesity: Halting the epidemic by making health easier. (http://www.cdc.gov/chronicdisease/resources/publications/AAG/obesity. htm, downloaded May 26, 2011). Cepeda-Benito, A., Gleaves, D. H., Williams, T. L., & Erath, S. A. (2000). The development and validation of the State and Trait Food-Cravings Questionnaire. Behaviour Therapy, 31, 151–173. Davis, C., Levitan, R. D., Reid, C., Carter, J. C., Kaplan, A. S., Patte, K., et al. (2009). Dopamine for “wanting” and opiods for “liking”: A comparison of obese adults with and without binge eating. Obesity, 17, 1220–1225. de Man Lapidoth, J., Ghaderi, A., & Norring, C. (2011). Binge eating in surgical weight-loss treatments: Long-term associations with weight loss, health related quality of life (HRQL) and psychopathology. Eating and Weight Disorders, 16, e263–e269. Engelberg, M., Steiger, H., Gauvin, L., & Wonderlich, S. A. (2007). Binge antecedents in bulimic syndromes: An examination of dissociation and negative affect. International Journal of Eating Disorders, 40, 531–536. Fairburn, C. G., & Cooper, Z. (1993). The eating disorder examination. In C. G. Fairburn, & G. T. Wilson (Eds.), Binge eating: Nature, assessment, and treatment (pp. 317–360) (12th ed.). New York: Guilford Press. First, M. B., Spitzer, R. L., Gibbon, M., & Williams, J. B. W. (2002). Structured Clinical Interview for DSM-IV-TR Axis I Disorders, Research Version, Patient Edition. (SCID-I/P). New York: Biometrics Research, New York State Psychiatric Institute. Greeno, C. G., Wing, R. R., & Shiffan, S. (2000). Binge antecedents in obese women with and without binge eating disorder. Journal of Consulting and Clinical Psychology, 68, 95–102. Grilo, C. M., Masheb, R. M., Lozano-Blanco, C., & Barry, D. T. (2004). Reliability of the Eating Disorder Examination in patients with binge eating disorder. International Journal of Eating Disorders, 35, 80–85. Hudson, J. I., Lalonde, J. K., Berry, J. M., Pindyck, L. J., Bulik, C. M., Crow, S. J., et al. (2006). Binge-Eating Disorder as a distinct familial phenotype in obese individuals. Archives of General Psychiatry, 63, 313–319. Jansen, A. (1998). A learning model of binge eating: Cue-reactivity and cue exposure. Behaviour Research and Therapy, 36, 257–272. Jarosz, P. A., Dobal, M. T., Wilson, F. L., & Schram, C. A. (2007). Disordered eating and food cravings among urban obese African American women. Eating Behaviors, 8, 374–381. Karhunen, L. J., Lappalianen, R. I., Tammela, L., Turpeinen, A. K., & Uusitupa, M. I. J. (1997). Subjective and physiological cephalic phase responses to food in obese binge-eating women. International Journal of Eating Disorders, 21, 321–328. Kemps, E., & Tiggemann, M. (2007). Modality-specific imagery reduces cravings for food: An application of the Elaborate Intrusion Theory of Desire to food cravings. Journal of Experimental Psychology. Applied, 13, 95–104.
L. Ng, C. Davis / Eating Behaviors 14 (2013) 472–475 Laessle, R. G., & Schulz, S. (2009). Stress-induced laboratory eating behaviour in obese women with Binge Eating Disorder. International Journal of Eating Disorders, 42, 505–510. Lowe, M. R., & Butryn, M. L. (2007). Hedonic hunger: A new dimension of appetite. Physiology and Behavior, 91, 432–439. Moreno, S., Rodriguez, S., Fernandez, M. C., Tamez, J., & Cepeda-Benito, A. (2008). Clinical validation of the trait and state versions of the Food Craving Questionnaire. Assessment, 15, 375–387. Nederkoorn, C., Smulders, F. T. Y., & Jansen, A. (2000). Cephalic phase responses, cravings and food intake in normal subjects. Appetite, 35, 45–55. Redlin, J. A., Miltenberger, R. G., Crosby, R. D., Wolff, G. E., & Stickney, M. I. (2002). Functioning assessment of binge eating in a clinical sample of obese binge eaters. Eating and Weight Disorders, 7, 106–115. Sobik, L., Hutchison, K., & Craighead, L. (2005). Cue elicited craving for food: A fresh approach to the study of binge eating. Appetite, 44, 253–261.
475
Staiger, P., Dawe, S., & McCarthy, R. (2000). Responsivity to food cues in bulimic women and controls. Appetite, 35, 27–33. Temple, J. L., Bulkley, A.M., Badawy, R. L., Krause, N., McCann, S., & Epstein, L. H. (2009). Differential effects of daily snack food intake on the reinforcing value of food in obese and nonobese women. American Journal of Clinical Nutrition, 90, 304–313. Tuschen-Caffier, B., & Schlussel, C. (2005). Binge eating disorder: A new eating disorder or an epiphenomenon of obesity? In S. Munsch, & C. Beglinger (Eds.), Obesity and binge eating disorder (pp. 138–148). Basel, Switzerland: Karger. Vander Wal, J. S., Johnston, K. A., & Nikhil, D. (2007). Psychometric properties of the State and Trait Food Cravings Questionnaires among overweight and obese persons. Eating behaviors, 8, 211–223. Wilfley, D. E., Welch, R. R., Stein, R. I., Borman-Spurrell, E., Cohen, L. R., Saelens, B. E., et al. (2002). A randomized comparison of group cognitive-behavioural therapy and group interpersonal psychotherapy for the treatment of overweight individuals with binge-eating disorder. Archives of General Psychiatry, 59, 713–721.
Contents lists available at ScienceDirect
Eating Behaviors
Cravings and food consumption in binge eating disorder Longena Ng ⁎, Caroline Davis Department of Psychology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
a r t i c l e
i n f o
Article history: Received 5 April 2013 Accepted 14 August 2013 Available online 23 August 2013 Keywords: Binge Eating Disorder Food Cravings Questionnaire Food consumption
a b s t r a c t The purpose of this study was to extend existing work that examines the role of cravings in Binge Eating Disorder (BED). The current study uses a case–control design to establish a relationship between cravings and food exposure, and between cravings and food consumption in individuals diagnosed with BED. Twenty-nine females with BED, 40 obese controls, and 50 normal-weight controls were first presented with a neutral cue and completed a food-craving measure. They were then presented with their favourite snack food and completed the craving measure again, after which they were allowed to consume the food. The BED group had significantly higher scores for pre- and post-craving measures, and consumed more food compared to the controls. There was, however, no significant interaction between group and craving scores. Results also showed a positive correlation between food consumption and cravings scores both before and after food exposure for individuals with BED. The findings suggest that the level of cravings prior to food exposure may be sufficient to predict overeating in BED and that treatment may want to target this as a defining feature that differentiates individuals with BED from those who do not binge eat. Crown Copyright © 2013 Published by Elsevier Ltd. All rights reserved.
1. Introduction The reduction in obesity is an important public health objective because of its association with high morbidity and mortality (Centre for Disease Control and Prevention, 2011). One contributor to the rising obesity rates is compulsive overeating — a hallmark criterion for Binge Eating Disorder (BED). To date, however, effective treatments for BED are generally lacking, in part, due to our incomplete understanding of the antecedents to binge episodes (Hudson et al., 2006; Temple et al., 2009). Some established binge-eating triggers include boredom, stress, fatigue, and low mood (Engelberg, Steiger, Gauvin, & Wonderlich, 2007; Laessle & Schulz, 2009; Redlin, Miltenberger, Crosby, Wolff, & Stickney, 2002). Food cravings have also been cited as a precipitant to binge episodes (Greeno, Wing, & Shiffan, 2000; Jansen, 1998). Appetite ratings and desire for food are typically measured through self-report — and believed to be the better assessment tools as they display stronger cue-specificity (Carter & Tiffany, 1999) — although physiological measures, such as heart rate and skin temperature, have also served as proxy indicators (Nederkoorn, Smulders, & Jansen, 2000). Studies have shown that those with eating disturbances report higher levels of cravings and food intake when exposed to a food cue compared to normal eaters (Sobik, Hutchison, & Craighead, 2005; Staiger, Dawe, & McCarthy, 2000). Currently only three studies have examined cravings in BED, showing that binge-eaters report higher levels of hunger and cravings than those who do not binge eat (Greeno et al., 2000; Jarosz, Dobal, ⁎ Corresponding author at: Centre for Addiction and Mental Health, 455 Spadina Avenue, Suite 200, Toronto, ON M5S 2G8, Canada. Tel.: +1 416 535 8501x77758. E-mail address: [email protected] (L. Ng).
Wilson, & Schram, 2007; Karhunen, Lappalianen, Tammela, Turpeinen, & Uusitupa, 1997). Some of the limitations of these studies were small sample sizes, the use of non-validated craving measures, and inclusion of those with BED and bulimia nervosa in the same group. The primary purpose of this study was to address the limitations of existing work on cravings in BED. To our knowledge, the current study is the first to compare women diagnosed with BED according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR; American Psychiatric Association, 2000) with appropriate control groups on food intake and cravings by using a well-validated multiitem craving scale. This study also assessed relationships between food exposure, food consumption, and cravings. Both normal-weight and weight-matched controls were used in order to ensure that the findings were attributable to the underlying eating pathology and not to other factors. Individuals with BED generally have a higher BMI than average; hence, it was particularly important to ensure that the results were not merely a facet of elevated weight (Greeno et al., 2000; Wilfley et al., 2002). It was hypothesized that there would be a significant interaction between time (cravings before and after food exposure) and group as well as main effects for time and group. Specifically, it was anticipated that BED participants would have higher craving scores compared to the control groups and all participants would have higher craving scores after food exposure than before exposure. It was also expected that individuals with BED would consume a significantly greater proportion of food than the controls, and that this would be independent of selfreported hunger (e.g., self-reported hunger ratings would not differ between the groups). Finally, it was predicted that cravings scores after presentation of the craved food would be positively correlated with percentage of food consumed for all participant groups.
1471-0153/$ – see front matter. Crown Copyright © 2013 Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.eatbeh.2013.08.011
L. Ng, C. Davis / Eating Behaviors 14 (2013) 472–475
473
2. Methods
2.3. Procedure
2.1. Participants
Potential participants were contacted by telephone and reported their weight and height to determine a provisional BMI for group assignment. Once deemed eligible, participants were asked about their most preferred snack food. Typical foods included chocolate, chips, and candy; no healthy foods such as apples or carrot sticks were requested. They were also told to consume a normal meal two hours prior to the study. On the day of testing, the SCID-I/P interview was administered to determine if the exclusion criteria were met. When appropriate, they were asked questions from the DSM-IV-TR and the EDE to determine a diagnosis of BED and the frequency of binge episodes. Next, they rated their current degree of hunger. Participants were then asked to look at a pencil (the control cue) prior to completing the FCQ-S, which instructed them to rate their cravings for their favourite snack food. Following these baseline measures, participants were given their selected snack food (which had been purchased prior to the testing session), after which they completed the FCQ-S again. At this point, participants were left alone for 15 min to complete some filler questionnaires. During that time participants were told they could consume the snack if they wished. At the end of the study, the snack was weighed if any remained. Participants were debriefed and paid a small stipend for their time and travel expenses.
Participants were pre-menopausal women between 25 and 50 years old recruited from advertisements placed at universities, hospitals, newspapers and online sites such as Craigslist. There were 29 obese participants with BED, 40 obese controls and 50 normal-weight controls. The mean monthly frequency of binge eating episodes in the BED group was 8.7. This study was approved by the York University ethics committee and was performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki. Exclusion criteria included current pregnancy (or a birth within the last 12 months), history of substance disorder, psychotic disorder, or currently participating in a weight-loss program or diet. The presence of any disordered eating behaviours, including binge-eating, was an additional exclusion criteria for the control groups. 2.2. Materials 2.2.1. Structured Clinical Interview for the DSM-IV-TR Axis I Disorders, Research Version, Patient Edition The Structured Clinical Interview for the DSM-IV-TR Axis I Disorders, Research Version, Patient Edition (SCID-I/P; First, Spitzer, Gibbon, & Williams, 2002) was used to screen for the Axis I disorders discussed in the exclusion criteria. Criteria found in Appendix B of the DSM-IVTR were used to diagnose BED.
2.2.2. Eating Disorder Examination Selected items from the Eating Disorder Examination (EDE; Fairburn & Cooper, 1993) were used to provide information about binge episodes (e.g., frequency). The EDE has shown good inter-rater reliability (r N .95) and test–retest reliability (r N .70) in assessing binge episodes (Grilo, Masheb, Lozano-Blanco, & Barry, 2004; Wilfley et al., 2002). 2.2.3. Body Mass Index Body Mass Index (BMI) [weight (kilogram)/height (metre)2] was calculated from height and weight measured with participants wearing light indoor clothing and standing in stocking feet. 2.2.4. Current hunger A 100 mm visual analogue line was used to measure self-reported hunger with 0 indicating “no hunger at all”, and 100 mm indicating the “most hunger imaginable”. 2.2.5. Food consumption The proportion of food consumed was calculated by dividing weight (grams) of the un-finished food after the exposure from the baseline weight of the food; this was then subtracted from 1. 2.2.6. Food Cravings Questionnaire-State The Food Cravings Questionnaire-State (FCQ-S; Cepeda-Benito, Gleaves, Williams, & Erath, 2000) is a 15-item self-report state measure of food cravings. It comprises five subscales which measure a desire to eat, reinforcement and relief from negative affect states after eating, lack of control, and craving as a physiological state. The total score was used to measure overall craving. It has shown high internal consistency in obese and overweight subjects (α = .88; Vander Wal, Johnston, & Nikhil, 2007), and in patients with eating disorders (α = .69 to .92 for the subscales; Moreno, Rodriguez, Fernandez, Tamez, & Cepeda-Benito, 2008). The Cronbach's α coefficient in this study was .91.
3. Results 3.1. Descriptive statistics There were no significant differences between the three groups in age (p = .11), marital status (p = .68), and ethnicity (p = .38). By design, the normal-weight controls had significantly lower BMIs than the obese controls and BED group, who did not differ from each other. See Table 1 for descriptive statistics. 3.2. Food cravings Repeated measures analysis of variance using Time (pre and post FCQ-S scores) as the within-subjects variable and Group as the between-subjects variable was used to assess cravings scores. There was a main effect of Group (F2, 116 = 8.55, p b .01) and Time (F1, 117 = 61.609, p b .001), but contrary to our hypothesis, the interaction was not statistically significant (p = .52). As expected, FCQ-S scores were higher after food exposure than before exposure. Tukey's post hoc analyses revealed that BED had significantly higher scores for pre and post FCQ-S compared to obese (p b .05) and normal-weight controls (p b .001), who did not differ from each other (see Fig. 1). 3.3. Food consumption Analysis of co-variance (ANCOVA) with Percentage of Food Consumed as the dependent variable, Group as the independent variable, and Hunger ratings as the covariate indicated a significant Group effect (F2, 116 = 2.66, p b 0.001). As hypothesized, the BED group consumed significantly greater proportions of food compared to the obese (p b .001) and normal-weight (p b .001) controls with no significant differences between the control groups (see Table 1). There
Table 1 Descriptive statistics (means and standard deviations) by group.
BMI Hunger (cm) Food consumed (%)
BED
Obese
Normal-weight
F
36.16(9.25)a 4.20(2.18) 57.38(.44)a
36.68(5.64)a 3.21(2.15) 16.67(.25)b
22.13(1.68)b 3.61(2.52) 22.79(2.66)b
89.09 b .001 1.645 .20 16.09 b .001
Note: a and b denote significance at p b .001.
p
474
L. Ng, C. Davis / Eating Behaviors 14 (2013) 472–475
Lapidoth, Ghaderi, & Norring, 2011), determining whether decreased cravings and consumption are related to subsequent decreases in psychopathology and other correlates (e.g., self-esteem, body image) is an important next step. One limitation is that there may have been another antecedent that was not being measured in this study that was correlated or causing food consumption in BED. Further, the current research focused solely on women due to the greater number of females diagnosed with BED than males (Tuschen-Caffier & Schlussel, 2005). Future studies should consider extending the research to males. This study showed that food cravings to non-salient food cues are correlated to over-eating in BED and that this is not a result of hunger or calorie deprivation. This is important as it suggests that the level of cravings prior to food exposure is one of the defining features that differentiate BED from non-binging individuals and it is these “anticipatory” cravings that may consequently precipitate a binge.
Fig. 1. Mean scores (standard error of the mean) on the Food Craving Questionnaire-State before and after food exposure by group.
was no significant difference between the groups on hunger ratings (see Table 1). 3.4. Craving and food consumption Also as hypothesized, there was a significant positive correlation between percentage of food consumed and FCQ-S scores after food exposure for BED participants (r = .596, p b .001), obese controls (r = .454, p b .01) and normal-weight controls (r = .300, p b .05). Interestingly, we found a significant correlation between food consumed and FCQ-S prior to food exposure for the BED group only (r = .518, p b .05). 4. Discussion The purpose of this study was to address the limitations of existing researching on cravings and food consumption in those with BED. Our hypotheses were supported to some degree. Compared to both controls, individuals with BED had significantly higher craving scores before and after food exposure, and consumed a significantly greater proportion of food. Contrary to our predictions the interaction between group and craving scores was not significant. As expected, food cues elicit cravings and cue-elicited cravings were correlated with food consumption in all groups; however, uncued cravings were correlated with consumption only in the BED group. This suggests that explicit food cues may not be necessary to precipitate binges in individuals with BED. It is possible that these “baseline” cravings represent the anticipatory effect of food since participants were asked about their favourite snack food during the screening and may have expected the food during the study. Therefore it appears that these less salient stimuli, or the anticipation of the food, may have been sufficient to predict consumption in BED. This is consistent with existing literature which suggests that individuals with BED display greater hedonic hunger (a subjective state that occurs in the absence of an energy deficit and is largely regulated by the palatability of food) than those who do not binge eat (Davis et al., 2009; Lowe & Butryn, 2007). Gaining an understanding of the antecedents to binge episodes will contribute to the design of clinical interventions. For instance, Kemps and Tiggemann (2007) found that olfactory and visual imagery of nonfood items decreased cravings, and using imagery to decrease the anticipatory cravings in BED may be effective in the subsequent prevention of a binge episode. Given that BED in obese individuals is associated with greater comorbid psychopathology and poorer overall health outcomes compared to non-binging obese individuals (de Man
Role of Funding Sources Funding for this study was provided by a minor research grant from York University's Faculty of Health and the SSHRC Small Grants Program. Neither funding source had a role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication.
Contributors Dr. Ng designed the study, conducted literature searches, collected the data, conducted the statistical analyses, and wrote the first draft of the manuscript. Dr. Davis contributed to the study design, statistical analyses, and revisions of the manuscript. Both authors contributed to and have approved the final manuscript.
Conflict of Interest Drs. Ng and Davis declare that they have no conflicts of interest.
References American Psychiatric Association (2000). Diagnostic and statistical manual (4th ed., Text Revision )Washington, D.C.: American Psychiatric Association. Carter, B.L., & Tiffany, S. T. (1999). A meta-analysis of cue-reactivity in addiction research. Addiction, 94, 327–340. Centre for Disease Control and Prevention (2011). Obesity: Halting the epidemic by making health easier. (http://www.cdc.gov/chronicdisease/resources/publications/AAG/obesity. htm, downloaded May 26, 2011). Cepeda-Benito, A., Gleaves, D. H., Williams, T. L., & Erath, S. A. (2000). The development and validation of the State and Trait Food-Cravings Questionnaire. Behaviour Therapy, 31, 151–173. Davis, C., Levitan, R. D., Reid, C., Carter, J. C., Kaplan, A. S., Patte, K., et al. (2009). Dopamine for “wanting” and opiods for “liking”: A comparison of obese adults with and without binge eating. Obesity, 17, 1220–1225. de Man Lapidoth, J., Ghaderi, A., & Norring, C. (2011). Binge eating in surgical weight-loss treatments: Long-term associations with weight loss, health related quality of life (HRQL) and psychopathology. Eating and Weight Disorders, 16, e263–e269. Engelberg, M., Steiger, H., Gauvin, L., & Wonderlich, S. A. (2007). Binge antecedents in bulimic syndromes: An examination of dissociation and negative affect. International Journal of Eating Disorders, 40, 531–536. Fairburn, C. G., & Cooper, Z. (1993). The eating disorder examination. In C. G. Fairburn, & G. T. Wilson (Eds.), Binge eating: Nature, assessment, and treatment (pp. 317–360) (12th ed.). New York: Guilford Press. First, M. B., Spitzer, R. L., Gibbon, M., & Williams, J. B. W. (2002). Structured Clinical Interview for DSM-IV-TR Axis I Disorders, Research Version, Patient Edition. (SCID-I/P). New York: Biometrics Research, New York State Psychiatric Institute. Greeno, C. G., Wing, R. R., & Shiffan, S. (2000). Binge antecedents in obese women with and without binge eating disorder. Journal of Consulting and Clinical Psychology, 68, 95–102. Grilo, C. M., Masheb, R. M., Lozano-Blanco, C., & Barry, D. T. (2004). Reliability of the Eating Disorder Examination in patients with binge eating disorder. International Journal of Eating Disorders, 35, 80–85. Hudson, J. I., Lalonde, J. K., Berry, J. M., Pindyck, L. J., Bulik, C. M., Crow, S. J., et al. (2006). Binge-Eating Disorder as a distinct familial phenotype in obese individuals. Archives of General Psychiatry, 63, 313–319. Jansen, A. (1998). A learning model of binge eating: Cue-reactivity and cue exposure. Behaviour Research and Therapy, 36, 257–272. Jarosz, P. A., Dobal, M. T., Wilson, F. L., & Schram, C. A. (2007). Disordered eating and food cravings among urban obese African American women. Eating Behaviors, 8, 374–381. Karhunen, L. J., Lappalianen, R. I., Tammela, L., Turpeinen, A. K., & Uusitupa, M. I. J. (1997). Subjective and physiological cephalic phase responses to food in obese binge-eating women. International Journal of Eating Disorders, 21, 321–328. Kemps, E., & Tiggemann, M. (2007). Modality-specific imagery reduces cravings for food: An application of the Elaborate Intrusion Theory of Desire to food cravings. Journal of Experimental Psychology. Applied, 13, 95–104.
L. Ng, C. Davis / Eating Behaviors 14 (2013) 472–475 Laessle, R. G., & Schulz, S. (2009). Stress-induced laboratory eating behaviour in obese women with Binge Eating Disorder. International Journal of Eating Disorders, 42, 505–510. Lowe, M. R., & Butryn, M. L. (2007). Hedonic hunger: A new dimension of appetite. Physiology and Behavior, 91, 432–439. Moreno, S., Rodriguez, S., Fernandez, M. C., Tamez, J., & Cepeda-Benito, A. (2008). Clinical validation of the trait and state versions of the Food Craving Questionnaire. Assessment, 15, 375–387. Nederkoorn, C., Smulders, F. T. Y., & Jansen, A. (2000). Cephalic phase responses, cravings and food intake in normal subjects. Appetite, 35, 45–55. Redlin, J. A., Miltenberger, R. G., Crosby, R. D., Wolff, G. E., & Stickney, M. I. (2002). Functioning assessment of binge eating in a clinical sample of obese binge eaters. Eating and Weight Disorders, 7, 106–115. Sobik, L., Hutchison, K., & Craighead, L. (2005). Cue elicited craving for food: A fresh approach to the study of binge eating. Appetite, 44, 253–261.
475
Staiger, P., Dawe, S., & McCarthy, R. (2000). Responsivity to food cues in bulimic women and controls. Appetite, 35, 27–33. Temple, J. L., Bulkley, A.M., Badawy, R. L., Krause, N., McCann, S., & Epstein, L. H. (2009). Differential effects of daily snack food intake on the reinforcing value of food in obese and nonobese women. American Journal of Clinical Nutrition, 90, 304–313. Tuschen-Caffier, B., & Schlussel, C. (2005). Binge eating disorder: A new eating disorder or an epiphenomenon of obesity? In S. Munsch, & C. Beglinger (Eds.), Obesity and binge eating disorder (pp. 138–148). Basel, Switzerland: Karger. Vander Wal, J. S., Johnston, K. A., & Nikhil, D. (2007). Psychometric properties of the State and Trait Food Cravings Questionnaires among overweight and obese persons. Eating behaviors, 8, 211–223. Wilfley, D. E., Welch, R. R., Stein, R. I., Borman-Spurrell, E., Cohen, L. R., Saelens, B. E., et al. (2002). A randomized comparison of group cognitive-behavioural therapy and group interpersonal psychotherapy for the treatment of overweight individuals with binge-eating disorder. Archives of General Psychiatry, 59, 713–721.
