Literature Review on Bulimia Nervosa and its Relation to the Personality Trait Introversion

Bulimia nervosa (BN) is one of the three major eating disorders commonly addressed in the field of psychology. The disorder is primarily characterized by an abnormal eating behavior that usually involves binging on food for a certain period of time as a response to personal stressors. Often referred to as a binge/purge syndrome, the eating disorder may involve such behaviors as induced vomiting, laxative and diuretic abuse, excessive exercise and unnecessary fasting. The disease usually has an onset age between 15 and 18 years and is said to affect 1-5% of (young) women in general.

The disorder is generally hard to detect due to several reasons. These reasons include: a) bulimics are good at hiding their rituals; b) most weigh within normal range for their height, sex and age and only a few are under or overweight; and c) they demonstrate appropriate and normal eating habits in public circumstances. Furthermore, “eating disorders have for a long time been thought of as a culture-bound syndrome concerning white, middle class women, and often have not been thought to exist in other societies or cultures.

However, studies show that eating disorders are present also in non-western societies, though not as prevalent” (Ekeroth, 2005, p. 19). Some signs and symptoms bulimics may exhibit include dental and gum diseases due to gastric acid exposure; irregular menstrual periods; swollen parotid glands; gastrointestinal problems such as bloating, constipation, and ulcers (gastric and duodenal); and electrolyte imbalances as a result of dehydration with accompanying symptoms such as hypotension, dizziness and light headedness (Sewell, 2000 ,p. 5-6).
The diagnosis of BN is primarily accomplished through the determination of the following criteria: “: a) recurrent episodes of binge eating (rapid consumption of a large amount of food in a discrete period of time); b) a feeling of lack of control over eating behavior during the eating binges; c) regularly engaging in self-induced vomiting, the use of laxatives or diuretics, strict dieting or fasting, or vigorous exercise in order to prevent weight gain; d) a minimum of two binge-eating episodes a week for at least three months; and e)
persistent over concern with body shape and weight” (Sewell, 2000, p. 6). In the paper written by Tracy Sewell (2000), she discusses the prevalence of eating disorders (ED) as affecting an estimated 2-3% of post pubertal girls and women with an additional 5-10% of whom have “subclinical” eating disorders. Apparently, a significant number of girls are psychologically distressed suffering in quiet disturbance which makes their cries for help harder to hear and easier to ignore.
As it were, girls tend to perceive their bodies, as it moves away from the thin prepubertal look, as overweight – resulting in unhappy feelings and the development of maladaptive methods of coping such as extreme dietary measures (p. 98-99). Sewell (2003) discusses several variables as affecting the incidence of the disorder. One such variable researchers have often associated with the disorder is the self-esteem levels/values of women.
Issues often surrounding the disorder include body shape dissatisfaction which have been found to be highly correlated with the disorder as having both a mediating and moderating effect depending on outcome measures used. Additionally, she notes that “disordered eating can be conceptualized along a continuum, ranging from concern with weight and normal eating, to “normative discontent” with weight and moderately deregulated/restrained eating, to anorexia nervosa and bulimia nervosa” (3).
“Normative discontent,” however, does not necessarily mean a psychiatric diagnosis or categorization, the condition itself – in its own right – can cause considerable distress and thus is a potential risk factor for developing BN syndrome (3). Perception plays a vital role in the pathology of the disorder. Most studies done on the subject reveal that bulimic women tend to report significant distortion of their body parts. They are greatly dissatisfied with their bodies which lead them to perceive themselves as larger than they really are and thus desire to become much smaller (Sewell, 2000, p.
102). Apparently, there is a high connection between depression, body esteem, body image pre-occupation (Sewell, 2000, p. 103); Baigrie & Giraldez, 2008, p. 173; Watson, 2008, p. 6-7) teasing, anxiety, hostility, boredom, dietary restraint (Baigrie & Giraldez, 2008), neuroticism, obsessive compulsive disorders [OCD], borderline personality disorder [BPD] and extroversion (Watson, 2008, p. 6-7) with the development of eating disturbances in young women with low self-esteem.
Sewell’s (2000) research into the subject of BN reveals that there are several correlated factors in the development of the disorder. One such factor is the onset of adolescence which is viewed as a turbulent time of “storm and stress” as the young woman’s family values come into conflict with societal, peer and media-espoused values. Numerous studies have established that adjustment problems peak during this time and thus contribute to the struggle for identity and independence (p. 6-7). Additionally, she found that certain predictive symptoms of BN can be found as soon as early childhood.
These include eating and digestive problems such as problems with self-control of eating behaviors as well as eating-related family struggles. Notably, it was discovered that parents of bulimics – most especially the father – demonstrated personality profiles suggestive of disturbed affect, weak internal controls, unmodulated expression of hostile impulses and absent emotionally satisfying intrafamilial ties. It was also found that relatives of bulimics were more likely to suffer frequently from affective disorders, alcoholism and drug use disorders (p.
8). Furthermore, it was discovered that the families of individuals with bulimia and bulimia-like symptoms were characteristically lacking in commitment, help, support, and filled with anger, aggression and conflict. Additionally, they were also found to be “disengaged, chaotic, conflictual, and lacking in expressive communication” (p. 9-10). It was also discussed in the same research that feminine and masculine traits were also correlated with the development of the disorder, especially towards the development of a distorted body-image.
Apparently in the case of eating disorders, feminine traits were valued negatively compared to masculine traits and this has led women to have more negative self-concepts than men do (Sewell, 2000, p. 11). In fact, it was found that: both masculine and feminine gender-typed women who strongly adhered to a superwoman ideal were at greater risk for eating disorders than androgynous superwomen were. In contrast, androgynous superwomen had relatively low potential for disordered eating and appeared comparable to women who regardless of gender typing rejected the superwoman ideal.
(Sewell, 2000, p. 13). Another area of correlation, according to the same research, is in the area of self-esteem. Apparently, low self-esteem is linked to indicators of psychological distress such as depression, neuroticism, anxiety, poor general adjustment and eating disorders. According to studies, it is generally accepted that those who have low self esteem have a greater risk of developing eating disorders (Sewell, 2000, p. 14). The issue of body image in bulimics has been found to have distinctions between body-size distortion and body dissatisfaction.
The former is described to be a “perceptual” disturbance where the patient appears unable to assess personal size accurately. The latter, on the other hand, has a more attitudinal (cognitive and affective) nature and has no disturbed size awareness. To quote: “ [in] this type patients assess their physical dimensions accurately but they react to their bodies with extreme forms of disparagement or occasional[] aggrandizement” (Sewell, 2000, p. 15). These two types are also known to operate separately or conjointly, depending on the complexity of the disorder.
Depression was also found to be highly correlated to the development of bulimia. Research indicates that around 60% of all bulimics suffer from a form of depression and that these feelings may be rooted in troubles with socialization. Studies have shown that socialization encourages the development of feminine characteristics in young women, however, the same activity also predispose them to develop “learned helplessness” – a form of maladaptation pattern towards stress.
This may be due to the imposition of the “thin ideal” primarily on women which results in the higher frequency of depression in the group (Sewell, 2000, p. 16). In fact it was found that “depression was related to eating attitudes in fifth and sixth grade girls [which] suggest that preoccupation with food and dieting in girls begins in the fifth and sixth grades and increases in the seventh and eighth grades, a time when most girls are completing puberty” (Sewell, 2000, p. 18).
Additionally, Sewell (2000) described in her research two sets of variables which the author predicted to have either predisposing effects (variables A) or precipitating effects (variables B) on the development of eating disorders. Findings for the research indicated that variables designated as B (which included self esteem and body shape dissatisfaction) had a more direct relationship in predicting eating disorder risk (p. 50-51). Apparently, it was also found that dieting can be an entree into an eating disorder especially if it were accompanied by certain risk factors and intensified by certain issues (p.
51). Other findings discussed by the author included several psychological measures designed to estimate the presence of risk factors such as the Rosenberg Self-Esteem Inventory, Body Shape Questionnaire, endorsed sex roles, Social Insecurity Subscale and the Interoceptive Awareness Subscale (Sewell, 2000, p. 52-53, 57, 106, 108). According to the research, those who are at risk of developing eating disorders usually score high in the Rosenberg Self-Esteem Inventory – a measure indicating the presence of lowered self-esteem.
Scoring high in the Body Shape Questionnaire test, on the other hand, indicates greater body shape dissatisfaction. These two measures combined indicate a greater risk for respondents falling within the clinical diagnosis range (p. 52-53). In terms of reported sex role, those who endorsed an androgynous sex role orientation were found to have higher body mass indices (BMI) and scored lowest in the Eating Attitudes Test (EAT), supporting findings in literature which state that those individuals with a more androgynous sex-role orientation generally score highest in self-esteem (p.
57). Meanwhile, high scores on the Social Insecurity Subscale reflects the level of perceived tension, insecurity, disappointment, unrewarding and generally poor quality of social relationships while the Interoceptive Awareness Subscale, on the other hand, measures confusion and apprehension in recognizing and accurately responding to emotional states.
It also reflects one’s lack of confidence in recognizing and accurately identifying sensations of hunger and satiety (p. 108). Interpreting these various data led Sewell (2000) to the following conclusions: numerous literatures indicate decreased self-esteem leads to a greater likelihood of being diagnosed with an eating disorder.
Similarly, increased body shape dissatisfaction and poor body image are strongly related to eating disorders and those individuals who indicated they “always” exercise were more likely to be diagnosed with an eating disorder than those who indicated they exercised less frequently. This also agrees with findings in the literature that indicates individuals who have an eating disorder are inclined to engage in great amounts of exercise, rather than exercise in moderation. (p. 52-53).
These, therefore, are the gist of Sewell’s findings on BN and other eating disorders: a) the disorder is highly predisposed by depression; b) several complex co-morbidities precipitate the development of eating disorders; c) failed, faulty or maladaptive social and familial interactions can affect the likeliness of developing the eating disorders; and d) BN and other eating disorders display high levels of body distortion and dissatisfaction which all point towards lowered body and self esteems.
In a separate study conducted by Kerstin Ekeroth (2005) where the author tackled psychological problems in adolescents and young women, she found that “patients with bulimia nervosa (BN) scored higher than both patients with anorexia nervosa (AN) and those with an eating disorder not otherwise specified (EDNOS) on most problem scales,” supporting the findings of Sewell and other literatures. Additionally, the author also mentions that AN-bingers/purgers (an AN subclass similar in behavior with bulimics) scored higher in externalizing behaviors than pure restrictors (p. 4).
In terms of co-morbidity, the author also found strong relations with depression. However, the author also warns that starvation may cause symptoms similar to primary depressive disorder and thus has a potential to influence initial depression ratings. Similarly, it was also found that there are elevated frequencies of social phobia in both AN and BN patients. In fact, an estimated 75% of AN and 88% of BN patients had anxiety disorders predating the eating disorder (Ekeroth, 2005, p. 25-26). Additionally, the author described several personality disorder clusters usually found in persons with eating disorders.
According to this description, BN patients most commonly demonstrate cluster B personality disorders. Cluster B personality disorders include borderline, antisocial, histrionic, and narcissistic personality disorders. Among these, it was found that borderline personality disorder is the most frequently reported. Additionally, BN patients also categorize under a cluster labeled C which includes disorders such as avoidant, dependent and obsessive-compulsive personality disorders. Apparently this cluster is commonly reported equally in both BN patients and AN patients (Ekeroth, 2005, p.
27-28). Several studies have also reported that a higher frequency of suicidal behavior, drug use, and stealing are found in girls with BN indicating impulsivity disorders. As the author writes: Bulimic behavior is often thought of as an expression or manifestation of a failure to control impulses to eat, and to get rid of the food afterwards. In addition, earlier studies have found that girls with bulimia not only have lower impulse control and elevated rates of impulsive behavior but also express more aggression compared to girls with AN.
(Ekeroth, 2005, p. 29). This is further supported by the fact that many patients with BN seem to have disinhibitory problems. A possible explanation for this is that dieting and starvation has been found to not only influence mood lability but is also disruptive to the different psychoneuroendocrinological systems (Ekeroth, 2005, p. 30). The author also discussed that patients with eating disorders often experience conflicted relations with friends and family, and usually withdraw from social interaction.
Despite this general characterization however, AN patients were found to be active in school and in sports. In complete contrast, BN girls were reported to have received less support from friends and family, experienced negative interactions and conflicts more frequently, and have less social competence (Ekeroth, 2005,p. 32). Furthermore, correlations identified by the author revealed the following data: [C]orrelations between the internalizing and externalizing dimensions were 0. 51/0.
49 (boys/girls), and for anxious/depressed, and aggressive behavior the correlations were 0. 49/0. 45 (boys/girls). Moreover, self-destructive/identity problems correlated high with anxious/depressed (r = 0. 78/0. 82 boys/girls) as well as with the internalizing dimension (r = 0. 77/0. 78 boys/girls) (Ekeroth, 2005, p. 40), revealing that a high correlation exists between self-destructive/identity problems with anxiety/depression and internalizing dimensions of persons with eating disorders.
Other findings included in the paper also reveal that BN patients score higher on somatic complaints, attention problems, delinquent behavior, aggressive behavior, externalizing, and total problems compared to AN and EDNOS patients. This was supported by the fact that BN patients report higher degrees of problem externalization especially concerning delinquent behaviors compared to AN patints (Ekeroth, 2005, p. 43). Additionally, BN patients were also reported to have more problems compared with AN patients.
Similarly, BN patients were also reported to have more problems “than EDNOS patients on anxious/depressed, self-destructive/identity problems and internalizing” (Ekeroth, 2005, p. 41). These findings were in line with previous reports that girls with ED score significantly lower on competence, interpersonal sensitivity, depression, anxiety, and psychoticism (Ekeroth, 2005, p. 48) – reinforcing the idea that “[f]eelings of self-competence and having close and good relations to family and peers might be important factors influencing coping potential and treatment outcome” (Ekeroth, 2005, p.
43) of patients with eating disorders. Evidently, lack of competence is on of the common features in persons with eating disorders. However, like most constructs, this aspect is not easily defined (Ekeroth, 2005, p. 58). Additionally, the author discusses: Bulimic behavior has been linked to impulsivity…[h]owever, the definition of impulsivity is not clear-cut and simple. Impulsivity consists of two different aspects, lack of planning and urgency (the tendency to act rashly when experiencing negative affect), and that it is urgency, which is linked to bulimic behavior.
Others have pointed at the distinction between internally and externally directed impulsive behavior, and suggest that general psychopathology is related to internally directed impulsivity (e. g. self-harm), while bulimic pathology is more specifically associated to externally directed impulsivity (e. g. theft). (Ekroth, 2005,p. 53). However, despite all these information, it is still generally regarded that there is still large uncertainty about the relevant distinction between AN-r (restrictive type), AN-b/p (binging/purgative type), and BN.
(Ekeroth, 2005, p. 33). The findings in both Sewell’s and Ekeroth’s research were also supported by a third study conducted by Baigrie and Giraldez (2008). The focus of this study however was on the subject of binge eating and its relation to coping strategies employed by [Spanish] otherwise normal adolescents. In the said study, it was found that among respondents for the study, those who reported binge eating characteristically had higher BMIs, lower self esteem, depressive symptoms and were less satisfied with their body image (p. 173).
Additionally, the study also determined that those who scored higher in the Eating Disorders Inventory (EDI) were more likely to have lower self esteem, more irrational thinking, decreased use of cognitive and behavioral coping strategies and increased use of avoidance coping (p. 174). In terms of coping strategies, the study found that the binge-eating group scored highest in three of the four areas of coping (introversion, positive hedonist coping, and avoidance coping) with introversion and avoidance coping garnering higher mean scores (Baigrie and Giraldez, 2008, p.
177). As the author’s discussed: it was expected that the adolescents who binge eat would use more avoidance coping strategies (unproductive coping) and fewer problem-focused strategies (positive coping) compared to the adolescents who do not binge eat. The results confirmed [that] adolescents who binge eat use avoidance coping more frequently than those who do not binge eat. (Baigrie and Giraldez, 2008, p. 177). Several studies also focused on the aspect of extraversion and introversion in correlation with eating disorders (Miller et al.
, 2005; Hitti, 2008; Watson, 2008[? ], p. 6-10,23; Carmo and Leal, 2007, p. 1). In these studies, it was found that lower extraversion (i. e. introversion) was related to disordered eating especially in women who score high in neuroticism – indicating that neuroticism and introversion may be risk factors in developing eating disorders (Miller et al. , 2005). This is supported by all previously discussed literature and by Miranda Hitti (2008) in her article where she states “shyness and introversion are risk factors for anxiety disorders, especially social anxiety disorder.
” As previously discussed, anxiety disorders are common co-morbidities among persons with eating disorders. An assumption can therefore be made that since neuroticism and introversion are risk factors for developing anxiety disorders, they are therefore indirect factors towards the development of eating disorders such as bulimia. Additionally, in the study conducted by Isla Watson (2008), it was determined that extroversion has a negative relation with eating disorders.
Extroversion is defined as being markedly engaged with the world and dealing with external factors in an energetic, positive manner such that extroverted individuals gain pleasure from attention and their actions are often spontaneous and lack regard for others. Furthermore, “[c]ompelling evidence has shown that extroversion increases after weight is restored during recovery from an eating disorder” and that it is often not expressed in anorexic individuals therefore calling for a need to watch out for the polar trait introversion (Watson, 2008, p.
10) due to the fact that introversion is a common feature of eating disorders (Watson, 2008, p. 23). This idea is further reinforced by the findings of Claudia Carmo and Isabel Leal where the authors negatively correlated extroversion and awareness with the Eating Disorders Inventory (EDI) subscales, allowing the authors to conclude that extroversion and awareness are protective factors against the development of eating disorders (p. 1).
In summary of all the literature discussed so far, the subject of BN and eating disorders in general seem to be highly correlated and associated with anxiety and personality disorders. It is also pointed out that these psycho-behavioral disorders are a probable result of several contributing factors such as families that are disengaged, chaotic, conflictual, and lacking in expressive communication, negative self concepts, and poor quality of social relationships.
These factors contribute to the development of depression, neuroticism, anxiety, poor general adjustment and lowered self esteem. Furthermore, these mentioned characteristics also define personality clusters found in persons with eating disorders such as BN. Though BN patients are generally more aggressive and demonstrative of delinquent behavior, distinctions between BN, AN-r, AN b/p and EDNOS is not very clearly defined. Therefore, findings about extroversion and introversion may generally apply to all of these eating disorders.
If anything, the fact that extroversion is proven to be negatively related to eating disorders, the inverse thus is also plausible: introversion is positively related with eating disorders. How this affects BN however is still unclear since most of the literature discussed here so far characterize BN as specifically associated with externally directed impulsivity – a behavior that somewhat mirrors extroversion. However, since BN patients also have co-morbid anxiety and personality disorders it cannot be ruled out automatically that these individuals do not have introvertive traits.
The mere fact that the characteristics lowered self esteem, avoidant coping, decreased social competence, and social phobia frequently come up as descriptive traits of the anxiety and depressive disorders found in these individuals all point to the likelihood that these individuals may have some form of introversion and that BN patients probably compensates for this by “acting out” in order to cover for the insecurity that is very definitive of eating disorders. References
Baigrie, S. S. , Giraldez, S. L. (2008). Examining the relationship between binge eating and coping strategies and the definition of binge eating in a sample of Spanish adolescents. The Spanish Journal of Psychology vol. 11 no. 1:172-180. Carmo, C. , Leal, I. (2007). Dimnsions of personality and eating disorders. University of Algarve Portugal, Department of Psychology. Ekeroth, K. (2005). Psychological problems in adolescents and young women with eating disturbances.
Doctoral Dissertation for Goteborg University, Department of Psychology. Hitti, M. (2008). Variations in RGS2 Gene Linked to Shyness in Kids, Introversion in Adults. WebMD Health News Reviewed by Louise Chang, MD. Retrieved March 17, 2009 from http://www. webmd. com/mental-health/news/20080303/shyness-gene-teased-out Miller, J. L. , Schmidt, L. A. , Vaillancourt, T. , McDougall, P. and Laliberte, M. (2005).
Neuroticism and introversion: A risky combination for disordered eating among a non-clinical sample of undergraduate women. Elsevier Ltd. Sewell, T. (2000). Developing risk factor profiles for Anorexia and Bulimia Nervosa in young adults. Thesis for the University of Manitoba for the Faculty of Graduate Studies. National Lirary of Canada. Watson, I. (2008). Personality factors & their relation with attentional bias to food words. Rsearch for the University of Wales, Bangor.