Motivation and emotion/Book/2016/Anorexia nervosa and extrinsic motivation

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Anorexia nervosa and extrinsic motivation:
What extrinsic motivational factors contribute to anorexia nervosa?

Overview[edit | edit source]

Template:I would refer readers to the list of resources you have provided at the bottom of the page.

When Debra was 19 years old, she was admitted to a mental health centre. She weighed 29 kilos. Her liver, pancreas and kidneys were damaged, and she spent almost 2 months in hospital recovering. During this time, Debra received psychotherapy that helped her understand why her eating behaviour had become dangerous. She also engaged in a behaviour modification program that rewarded her with privileges for each kilo she gained. Slowly, she began to gain weight and through therapy began to understand why her eating behaviour had become dangerous. When she left the hospital, she weighed 48 kilos, and two years later, was maintaining a steady weight (Steele, 1977).

Debra's experience highlights the burden of anorexia, a debilitating eating disorder that leads to diminished quality of life, and serious adverse health effects. It is a complex disorder and has been the focus of research attempting to determine contributing factors and effective treatments. It also lends itself to many questions: What motivates an individual to engage in damaging eating habits? Are internal or external motivations responsible?

This chapter examines the external motivational factors that contribute to the development of anorexia. It will also attempt to answer some of the questions above, and hopefully answer your own questions; so if you have any, keep them in mind while you read.

Focus question

1. What extrinsic motivational factors contribute to anorexia nervosa?

Eating disorders[edit | edit source]

Eating disorders are characterised by persistent disturbance surrounding eating or eating-related behaviours, leading to significant psychological distress and impaired functioning, and in some cases, death (APA, 2013). It is estimated that approximately 4% of the Australian population has an eating disorder (Butterfly foundation, 2016), with at least 15% of women experiencing an eating disorder at some point in their life (NEDC, 2016). Some common eating disorders are listed in Table 1. Eating disorders are diagnosed in Australia through the Diagnostic and Statistical Manual, fifth edition, a clinical tool that lists currently recognised mental disorders, and includes various information about the different sub-types, causes and prevalence of these disorders (APA, 2013).

Figure 2. Australia has a network of eating disorder support groups.

Table 1. Summary of common eating disorders (National Institute of Mental Health (2017)

Common symptoms
Anorexia nervosa Extreme restriction of food intake, accompanied by excessive exercise and at times purging behaviours. (Vancampfort et al., 2014)
Bulimia nervosa Bingeing on sweet or high-caloric foods, and then purging through vomiting, or diuretic use. (Vancampfort et al., 2014)
Binge Eating Disorder Out of control consumption of large quantities of foods (usually within 2 hours) and is accompanied by feelings of guilt or distress after eating (Giel et al., 2022)

Note: An individual may have problems or issues surrounding eating and eating behaviours, but these will only fall under the definition of "eating disorder", if they cause significant impairment in that individual's life. For example, Eddie may be very focused on eating only vegetables and doing at least two hours of exercise every day, but until these behaviours start to interfere with other aspects of Eddie's life, he would not be diagnosed with an eating disorder (APA, 2013).

Anorexia nervosa[edit | edit source]

Figure 3. Restricted food intake is a common feature of anorexia

Anorexia is a serious eating disorder, clinically named Anorexia Nervosa. Anorexia can be identified by changes in an individual's thoughts, feelings and behaviour to lose weight. Common behavioural changes include excessively restricting food intake and engaging in regular, intense periods of physical activity (APA, 2013). Physical changes such as dizziness, disruptions of the menstrual cycle (in women), and the appearance of fine hair across the body, are also often present (NEDC, 2016). Psychological changes include a preoccupation with eating, intense fear of gaining weight, and a distorted body image (NEDC, 2016). Other symptoms include frequently checking weight, and measuring body parts (APA, 2013). Often, individuals with anorexia will see losing weight as extraordinary self-control and determination; gaining weight is seen as an unacceptable failure (APA, 2013).

People at risk[edit | edit source]

Anorexia usually develops in adolescence or young adulthood, between 15 and 19 years (Bulik, Reba, Siega-Riz, & Reichborn-Kjennerud, 2005). Statistics from the United States show that in 2007, the lifetime prevalence of anorexia was affecting 0.6% of the adult population, with lifetime prevalence rates for females at 0.9%, and 0.3% for males (Hudson, Hiripi, Pope, & Kessler, 2007). Other statistics suggest that anorexia is ten times more common among females than males (Rieger, 2014). However, the incidence of anorexia among males is increasing (Wooldridge, & Lytle, 2012).

Possible causes[edit | edit source]

Anorexia has no one single cause, although there are minor predispositions and precipitations that may be necessary for its development, they are not entirely sufficient for all cases of the development of the disorder (Morris & Taddle, 2007).

Biology[edit | edit source]

Although not entirely understood, biological factors, such as an inherited disposition or genetic abnormality may predispose an individual to developing anorexia. Research shows that families of individuals suffering from anorexia will likely present traits such as a disposition towards leanness, or a family history of obsessive-compulsive personalities, or mood disorders, all of which may have a genetic basis (Rieger, 2014). In fact, the risk for individuals who have an immediate family member diagnosed with anorexia is approximately seven to twelve times higher than for other individuals (Herpertz-Dahlmann, Seitz, & Konrad, 2011).

Psychology[edit | edit source]

Figure 4. Genetics likely plays a role in the development of anorexia.

Psychological factors such as dysfunctional thoughts have been identified as other possible factors that lead to anorexia. A European study in 2012 interviewed eight adolescents between the age of 13 and 17 years, to try and determine what psychological factors are present at the onset of anorexia. Results showed that a variety of overwhelming emotions, such as frustration, guilt and fear were present in participants before the onset of anorexia (Koruth, Nevison, & Schwannauer, 2012). Obsessiveness, perfectionism and competitive traits have also been found to be present in adolescents and adults with anorexia (Morris & Taddle, 2007). Furthermore, anorexia has also been found to occur in individuals who were well-behaved, hard-working and successful as children (Bruch, 1985, as cited in Herpertz-Dahlmann, Seitz, & Konrad, 2011).

Society[edit | edit source]

There are social implications associated with having eating disorders. Machado, Goncalves, Martins, Hoek, & Machado (2014) examined the possible social causes of anorexia, by comparing 86 women diagnosed with anorexia with two matched groups of either healthy individuals, or individuals with other mental disorders. Analysis revealed that the women with anorexia reported receiving negative or critical comments about their body shape, or weight, in the year preceding their diagnosis (Machado, Goncalves, Martins, Hoek, & Machado, 2014). Social favouring of certain body types may be a contributory factor; a study conducted in 1995 and 1998 examined the incidence of eating disorder symptoms among young Fijian women before, and after the introduction of television to their province. Results revealed that a greater percentage of women scored in the clinical range on an eating disorder questionnaire after exposure to television, compared to women who had not been exposed (Becker, Burwell, Gilman, Herzog, & Hamburg, 2002, as cited in Rieger, 2014).

Co-morbid disorders[edit | edit source]

Individuals with anorexia are often diagnosed with other mental disorders. Anxiety disorders are one of the most frequently reported disorders to co-occur with anorexia (Herpertz-Dahlmann, Seitz, & Konrad, 2011). Other co-occurring disorders include mood disorders, such as major depressive disorder, and personality disorders, such as obsessive-compulsive personality disorder (Rieger, 2014). A 2015 study of patients with severe anxiety disorders in Denmark found that individuals diagnosed with obsessive-compulsive disorder presented the greatest risk for anorexia (Meier, Bulik,Thornton, Mattheisen, Mortensen, & Peterson, 2015).

Treatment[edit | edit source]

[Provide more detail] Medical treatment. If undernourishment or starvation has started to break down your body, medical treatment will be the first priority. A GP will treat the medical conditions that have been caused by anorexia, such as, heart problems, or depression.


Setting[edit | edit source]

In this chapter's opening case study, Debra visited a mental health centre and a hospital (Steele, 1977). Recently, the treatment setting for individuals with anorexia has changed; rather than long-term hospital admittance, the individual will likely engage in a short-term hospital stay, followed by returning to a treatment centre several times a week. The individual may also remain at home and see a therapist several times a week (Rieger, 2014).

Psychotherapy[edit | edit source]

Psychological treatments involve a clinical psychologist, who helps the client understand their disorder and treat it. Individuals with anorexia often seen the disorder as a channel for achievement, with the result that some individuals do not want to change (Rieger, 2014). Motivational enhancement therapy aims to alter the client's motivation to change (Rieger, 2014). Cognitive Behavioural Therapy (CBT), is useful in cases where the client has motivation to treat their disorder, and is conducted over three phases, summarised below (Rieger, 2014). Interpersonal psychotherapy, deals with how the client relates to other people, and family therapy attempts to draw the focus of the client's family from the client's eating disorder, to relationships (Rieger, 2014). Currently, evidence supports the effectiveness of motivational enhancement therapy, CBT and family therapy in treating anorexia (Rieger, 2014). Interpersonal psychotherapy has also been supported for its long-term benefits in focusing on the client's relationship to others (Zipfel, et al., 2014, as cited in Bulik, 2014).

Table 2. Summary of the three phases of CBT in treating anorexia

Phase Action
1 Establishes the therapeutic relationships between the client and the psychologist, and creates meal plans with a dietitian.
2 Identifies the client's dysfunctional thoughts about their weight and eating, examining evidence for and against these thoughts, and replacing them with more realistic beliefs.
3 Concludes treatment and provides the client with strategies to prevent relapse.

Quick quiz[edit | edit source]

If you like, complete the following quiz to see if you recognise the basic causes, symptoms, and treatments for anorexia, before reading the rest of the chapter:

1 What is a common symptom of anorexia?

Disturbed body image.
Narcissism.
Over-eating.

2 Has the cause of anorexia been proven?

Yes, genetic factors are the cause.
No, but it is likely caused by a range of interacting factors
No, but it is likely caused psychological factors.

3 Choose a common co-morbid disorder of anorexia from the list below:

Anxiety disorders.
Psychotic disorders.
There are no co-morbid disorders of anorexia.

4 What is a common treatment for anorexia?

Encourage the client to eat more.
Sporadic change therapy.
Motivational enhancement therapy.


Introduction to motivation: basic definitions[edit | edit source]

Figure 5. If this batter is playing baseball because he loves the game, he is intrinsically motivated.

The rest of this chapter focuses on extrinsic motivations and anorexia; however, it is first important to understand some basic definitions of motivational concepts.

Motivation: an organism is moved to do something, implying a level of energy and direction in that movement; it is divided into two categories, intrinsic and extrinsic motivation (Ryan, & Deci, 2000c).

Extrinsic motivation:

"An incentive to do something that arises from factors outside the individual, such as rewards or penalties" (Law, 2016).

Intrinsic motivation:

"An incentive to do something that arises from factors within the individual, such as a need to feel useful or to seek self-actualization" (Law, 2016).

The distinction between extrinsic and intrinsic motivation is whether an incentive originates externally or internally, and is associated with losses and gains, or interest, respectively. Furthermore, an individual can be intrinsically motivated even if a task is difficult. Research has shown that greater levels of motivation are associated with intrinsic motivators, rather than extrinsic motivators (Reeve, 2015). While extrinsic motivation seems undesirable, research has also shown positive sides to extrinsic motivation, which we will discuss further.

Which one is extrinsic motivation? Which one is intrinsic motivation?

  1. Brendan does his homework because he doesn't want to fail his class.
  2. Sarah does her difficult guitar lessons because she really wants to learn a song she likes.

Self-determination theory[edit | edit source]

Several theories that focus on understanding how different types of motivation effect human behaviour have been proposed by researchers; the following is a short overview of a motivational theory that explores different facets of motivation, including extrinsic motivation.

Self-determination theory suggests that there are three basic psychological needs, competence, autonomy and relatedness, which lead to increased motivation and enhanced welfare (Ryan, & Deci, 2000a). Competence refers to the individual's need to feel control in their life. Autonomy refers to the individual's need to feel that one's behaviours and thoughts are guided from within, rather than exerted by external forces. Relatedness refers to the individual's need to experience a sense of connection to other individuals (Ryan, & Deci, 2000a). This theory suggests that these are fulfilled primarily through intrinsic motivation. This theory also acknowledges positive multidimensional aspects of extrinsic motivation, defining four types of extrinsic motivation, ranging from a state of amotivation (no motivation) to intrinsic motivation (Reeve, 2015). Self-determination theory also distinguishes between autonomous and controlled motivation; autonomous motivation describes a combination of intrinsic and extrinsic motivations, where behaviour is influenced by free incorporation of useful extrinsic motivators into one's identity. Controlled motivation is a combination of extrinsic motivational types that control an individual's behaviour through external pressures such as approval, or shame avoidance (Deci, & Ryan, 2008).

Understanding the relationship between anorexia and extrinsic motivations[edit | edit source]

Figure 6. Obedience training is an example of externally regulated behaviour.

Now, with an understanding of anorexia and some motivational concepts, we can discuss the relationship between extrinsic motivation and anorexia. The following is the final component of this chapter, and looks at the four types of extrinsic motivation and specific motivators that may play a role in the development of anorexia.

Levels of extrinsic motivation[edit | edit source]

Self-determination theory proposes several levels of extrinsic motivation, summarised in the table below (Deci, & Ryan, 2000b; Vallerand, 1997).

Table 3. Summary of the four levels of extrinsic motivation.

Level Effect on behaviour
External regulation Behaviour is strictly controlled by consequences.
Introjected regulation Behaviour is performed because of self-imposed pressures.
Identified regulation Behaviour is personally identified with.
Integrated regulation Behaviour is freely chosen & organised into the individual's identity

These levels distinguish between the influence of external pressures and free choice on behaviour (Vallerand, 1997), and may also explain anorexia development. Several different levels of extrinsic motivation are identifiable in anorexic behaviours. For example, anorexic eating behaviour is controlled by consequential weight-loss and is therefore externally regulated. A study in 2007 examined the role of extrinsic motivations in relation to exercise, body image and need satisfaction among a group of 149 aerobic instructors. Results found that introjected regulation demonstrated a negative relationship with body image and self-worth, suggesting that self-imposed pressures to exercise in order to achieve a desired body type, may have a negative effect on self-esteem, in turn possibly leading to anorexia (Thogersen-Ntoumani, & Ntoumanis, 2007). Identified regulation is also implicated; in a qualitative recovery study, anorexia survivors cited personally identifying with their disorder until it became a "way of life" (Weaver, Wuest, & Ciliska, 2005). Together, this research suggests that these different levels of extrinsic motivation may influence the development of anorexia. As well as these levels, specific extrinsic motivators may also contribute to the disorder.

Provide more in-text references


Two specific extrinsic motivators[edit | edit source]

[Provide more detail]

Body image[edit | edit source]

The promotion of certain body types may act as a powerful extrinsic motivator that contributes to the development of anorexia. Current media promotes an ultra-thin female body type that for many women is unattainable (Attie, & Brooks-Gun, 1989, as cited in, Hawkins, Richards, Granley, & Stein, 2004). As many young women are exposed to media daily, research has focused on the role that exposure to promotion of these body types has on anorexia development. In a revealing study, researchers exposed a mixed group of 145 women from the Ohio State University campus to images from popular magazines that were either neutral, or promoted an ultra-thin body type. Results revealed that women who were exposed to the ultra-thin images experienced greater body dissatisfaction, decreased self-esteem, increased negative mood and eating disorder symptoms (Hawkins, Richards, Granley, & Stein, 2004). Although limited by self-report measures (Hawkins, Richards, Granley, & Stein, 2004), this study presents that promotion of certain unattainable body-types may act as an extrinsic motivator for anorexia. A qualitative study discussing 28 women's battles with anorexia also highlighted the extrinsic motivational power of promoted body-types; while not blaming the media for the development of their disorder, participants acknowledged the influence of fashion magazine models (Thomsen, McCoy, & Williams, 2001). In the words of one participant:

"On my wall, I would cut out all the pictures of the models...I'd cut them and pin them up on my wall just like a motivator...I'd think, "Those are the legs I want. Those are the arms I want." And I just filled up my room with that and that was my goal" (Thomsen, McCoy, Williams, 2001).

Another study explored the relationship between associating underweight models with positive attributes, and eating disorder symptoms (Ahern, Bennett, & Hetherington, 2008). A sample of 99 female undergraduate students completed an implicit association test on weight, and a self-report measure assessing eating disorder symptoms and body dissatisfaction. Results revealed that participants associating being underweight with positive attributes, also presented elevated eating disorder symptoms (Ahern, Bennett, & Hetherington, 2008). While limited by possible sample bias (Ahern, Bennett, & Hetherington, 2008), this study also presents the importance of recognising the promotion of thin body types as an extrinsic motivator for anorexia.

Next time you're browsing the internet, count the number of times you see an attractive model who is very thin. Compare this with the number of times a model is a healthy weight.

Control[edit | edit source]

Another extrinsic motivator that has links to anorexia, is control. Attempting to gain control of life situations has been examined as a contributory extrinsic motivator of anorexia. The aforementioned qualitative study by Thomsen, McCoy and Williams (2001), found participants often described living in difficult family dynamics, which led to a desire to gain control, before developing anorexia. These familial situations often included parenting younger siblings and protecting mothers from abusive partners (Thomsen McCoy, & Williams, 2001). As one participant stated:

"I didn't want to be the cause of another problem ... it was easier for me to just worry about my body and exercise and food." (Thomsen, McCoy, & Williams, 2001).

Figure 8. For individuals with anorexia, weight-loss can be seen as gaining control, or achieving.

Research with anorexia survivors also shows that experience of difficult life circumstances, such as parental unemployment or divorce, contribute to a desire to take control (Weaver, Wuest, & Ciliska, 2005). One anorexia survivor pin-pointed the stress of moving house, and hearing that her parent's marriage was in trouble, as precursory events that led to anorexia (National health scheme, 2016). Another qualitative study of 12 female anorexia survivors found that participants saw the feeling of "taking control" by engaging anorexic behaviours, as a "lure" to engage in further anorexic behaviours (Weaver, Wuest, & Ciliska, 2005). Participants described feeling greater personal control and effectiveness when experiencing events such as a "running high" and lack of appetite after exercise; this encouraged the progression of anorexic behaviours, to the long-term development of anorexia (Weaver, Wuest, & Ciliska, 2005). Interestingly, this desire to take control is connected to a desire to "achieve something"; anorexia survivors often note that they wanted to feel better about themselves before engaging in anorexic behaviours. One anorexia survivor found that dieting led to immediate feelings of achievement.

"As I began to lose weight, I started to feel that life was worth living. At last I seemed to be achieving something." (National health scheme, 2016).

Another survivor's desire to achieve strongly motivated here to be constantly busy because she didn't want her friends and family to think she was "lazy" (Eating Disorders Victoria, 2016). Individuals who develop anorexia often present a strong drive for achievement (Weaver, Wuest, & Ciliska, 2005); it is no surprise that signs of immediate achievement such as weight-loss, are a major factor in anorexia. Although these studies rely on self-report, they present evidence that seeking to gain control of difficult life situations and to a desire to achieve, may act as extrinsic motivational factors that lead to and support anorexia.

Conclusion[edit | edit source]

This chapter has provided a brief overview of the factors that contribute to anorexia. We have explored eating disorders and anorexia, defined the different types of motivation, and examined how extrinsic motivations are related to anorexia. However, this chapter has only discussed two specific motivators; it is likely that individuals not yet included in research could define other extrinsic factors related to anorexia, a possible future direction for motivational research. During your journey through this chapter you have also been asked questions; perhaps you managed to answer these, perhaps you did not. However, hopefully this chapter has encouraged you to think on some challenging concepts, and overall, has left you with a more complete understanding of motivation.

Thank you for reading.

See also[edit | edit source]

References[edit | edit source]

Ahern, A. L., Bennett, K. M., & Hetherington, M. M. (2008). Internalization of the ultra-thin ideal: positive implicit associations with underweight fashion models are associated with drive for thinness in young women. Eating Disorders, 16, 294-307. doi: 10.1080/10640260802115852.

American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing.

Bulik, C. M., Reba, L., Siega-Riz, A., & Reichborn-Kjennerud, T. (2005). Anorexia Nervosa: Definition, Epidemiology, and Cycle of Risk. Psychopathology, 37, 2-9. doi: 10.1002/eat.20107

Bulik, C. (2014). The challenges of treating anorexia nervosa. The Lancet, 383, 105-106. doi: 10.1016/S0140-6736(13)61940-6

Butterfly Foundation for Eating Disorders. (2016). Understanding Eating Disorders & Body Image Issues. Retrieved from the Butterfly Foundation for Eating Disorders: https://thebutterflyfoundation.org.au/understand-eating-disorders/

Deci, E. L., & Ryan, R. M. (2008). Self-Determination Theory: A Macrotheory of Human Motivation, Development, and Health. Canadian Psychology, 49, 182-185. doi: 10.1037/a0012801

Eating Disorders Victoria (2016). Lauren's Recovery From Anorexia. Retrieved from Eating Disorders Victoria https://www.eatingdisorders.org.au

Hawkins, N., Richards, P. S., Granley, H. M., & Stein, D. M. (2004). The impact of exposure to the thin-ideal media image on women. Eating Disorders, 12, 35-50. doi: 10.1080/10640260490267751

headspace: the National Youth Mental Health Foundation. (2016). Who we are. Retrieved from headspace the National Youth Mental Health Foundation https://www.headspace.org.au/about-us/who-we-are/

Herpertz-Dahlmann, B., Seitz, J., & Konrad, K. (2011). Aetiology of anorexia nervosa: from a "psychosomatic family model" to a neuropsychiatric disorder?. European Archives of Psychology and Clinical Neuroscience, 261, 177-181. doi: 10.1007/s00406-011-0246-y

Hudson, J. I, Hiripi,. E, Pope, H. G, & Kessler, R.C (2007). The prevalence and correlates of eating disorders in the National Comorbidity Survey Replication. Biological Psychiatry, 61, 348-58. doi:10.1007/s00406-011-0246-y

Koruth, N., Nevison, C., & Schwannauer, M. (2012). A grounded theory exploration of the onset of anorexia in adolescence. European Eating Disorders Review, 20, 257-264. doi:10.1002/erv.1135

Law, J. (2016). A Dictionary of Business and Management (6th. ed.). Retrieved from http://www.oxfordreference.com.ezproxy.canberra.edu.au/view/10.1093/acref/9780199684984.001.0001/acref-9780199684984-e-2403

Machado, B. C., Goncalves, S. F., Machado, P. P., Martins, C., & Hoek, H. W. (2014). Risk factors and antecedent life events in the development of anorexia nervosa: A portuguese case-control study. European Eating Disorders Review, 22, 243-251. doi:10.1002/erv.2286

Morris, J., & Twaddle, S. (2007). Anorexia nervosa. BMJ (Clinical research ed.), 334(7599), 894–898. https://doi.org/10.1136/bmj.39171.616840.BE

National Eating Disorders Collaboration. (2016). What is an eating disorder? Retrieved from National Eating Disorders Collaboration: http://www.nedc.com.au/

National Health Scheme (2016). Anorexia nervosa - Katie's story Retrieved from National Health Scheme: http://www.nhs.uk/

Reeve, J. (2015). Extrinsic Motivation. In C, Johnson (Eds.), Understanding Motivation and Emotion (pp. 116-151). Hoboken, NJ: Wiley.

Rieger, E. (2014). Abnormal Psychology: Leading Researcher Perspectives (3rd. ed.). North Ryde, NSW: McGraw-Hill

Ryan, R. M., & Deci, E. L. (2000c). Intrinsic and Extrinsic Motivations: Classic Definitions and New Directions. Contemporary Educational Psychology, 25, 54-67. doi: 10.1006/ceps.1999.1020

Ryan, R. M., & Deci, E. L. (2000b). Self-determination theory and the facilitation of intrinsic motivation, social development and well-being. American Psychologist, 55, 68-78. doi: 10.1037110003-066X.55.1.68

Ryan. M., & Deci, E. L. (2000a). The "What" and "Why" of Goal Pursuits: Human Needs and the Self-Determination of Behavior. Psychological Inquiry, 11, 227-268. doi: 10.1207/S15327965PLI1104_01

Steele, R. L. (1977). Anorexia nervosa: a case study. Psychotherapy and Psychosomatics, 27, 47-53.

Thaler, L., Israel, M., Antunes, J. M., Sarin, S., Zuroff, D., & Steiger, H. (2016). An examination of the role of autonomous versus controlled motivation in predicting inpatient treatment outcome for anorexia nervosa. International Journal of Eating Disorders, 49, 626-629. doi: 10.1002/eat.22510

Thogersen-Ntoumani, C., & Ntoumanis, N. (2007). A Self-Determination Theory Approach to the Study of Body Image Concerns, Self-presentation and Self-perceptions in a sample of Aerobic Instructors. Journal of Health Psychology, 12, 301-315. doi: 10.1177/1359105307074267

Thomsen, S. R., McCoy, J. K., & Williams, M. (2001). Internalizing the impossible: anorexic outpatients' experiences with women's beauty and fashion magazines. Eating Disorders, 9, 49-64. doi: 10.1080/106402601300187731

Vallerand, R. J. (1997). Toward a Hierarchical Model of Intrinsic and Extrinsic Motivation. Advances in Experimental and Social Psychology, 29, 271-360. doi: 10.1016/S0065-2601(08)60019-2

Weaver, K., Wuest, J., & Ciliska, D. (2005). Understanding women's journey of recovering from anorexia nervosa. Qualitative Health Research, 15, 188-206. doi: 10.1177/1049732304270819

Wooldridge, T., & Lytle, P. (2012). An overview of anorexia nervosa in males. Eating Disorders, 20, 368. doi:10.1080/10640266.2012.715515

External links[edit | edit source]