Anorexia nervosa is an eating disorder characterized by weight loss (or lack of appropriate weight gain in growing children); difficulties maintaining an appropriate body weight for height, age, and stature; and, in many individuals, distorted body image. People with anorexia generally restrict the number of calories and the types of food they eat. Some people with the disorder also exercise compulsively, purge via vomiting and laxatives, and/or binge eat.
Anorexia can affect people of all ages, genders, sexual orientations, races, and ethnicities. Historians and psychologists have found evidence of people displaying symptoms of anorexia for hundreds or thousands of years. People in non-Westernized areas, such as rural China and Africa, have also been diagnosed with anorexia nervosa.
Although the disorder most frequently begins during adolescence, an increasing number of children and older adults are also being diagnosed with anorexia. Nor does a person need to be emaciated or underweight to have anorexia. Studies have found that larger-bodied individuals can also have anorexia, although they may be less likely to be diagnosed due to cultural prejudice against fat and obesity.
To be diagnosed with anorexia nervosa according to the DSM-5, the following criteria must be met:
1. Restriction of energy intake relative to requirements leading to a significantly low body weight in the context of age, sex, developmental trajectory, and physical health.
2. Intense fear of gaining weight or becoming fat, even though underweight.
3. Disturbance in the way in which one's body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of the current low body weight.
Even if all the DSM-5 criteria for anorexia are not met, a serious eating disorder can still be present. Atypical anorexia includes those individuals who meet the criteria for anorexia but who are not underweight despite significant weight loss. Research studies have not found a difference in the medical and psychological impacts of anorexia and atypical anorexia.
NEDA has gathered data on the prevalence of eating disorders from the US, UK, and Europe to get a better idea of exactly how common anorexia is. Older data from other countries that use more strict definitions of anorexia and bulimia give lower prevalence estimates:
- In a study of 31,406 Swedish twins born from 1935-1958, 1.2% of the women had strictly defined anorexia nervosa during their lifetime, which increased to 2.4% when a looser definition of anorexia was used (Bulik et al., 2006).
- For twins born between 1975 and 1979 in Finland, 2.2-4.2% of women (Keski-Rahkonen et al., 2007) and 0.24% of men (Raevuori et al., 2009) had experienced anorexia during their lifetime.
- At any given point in time between 0.3-0.4% of young women and 0.1% of young men will suffer from anorexia nervosa
Several more recent studies in the US have used broader definitions of eating disorders that more accurately reflect the range of disorders that occur, resulting in a higher prevalence of eating disorders.
- A 2007 study asked 9,282 English-speaking Americans about a variety of mental health conditions, including eating disorders. The results, published in Biological Psychiatry, found that 0.9% of women and 0.3% of men had anorexia during their life
When researchers followed a group of 496 adolescent girls for 8 years (Stice et al., 2010), until they were 20, they found:
- 5.2% of the girls met criteria for DSM5 anorexia, bulimia, or binge eating disorder.
- When the researchers included nonspecific eating disorder symptoms, a total of 13.2% of the girls had suffered from a DSM-5 eating disorder by age 20.
Combining information from several sources, Eric Stice and Cara Bohon (2012) found that
- Between 0.9% and 2.0% of females and 0.1% to 0.3% of males will develop anorexia
- Subthreshold anorexia occurs in 1.1% to 3.0% of adolescent females
Other statistics related to anorexia:
- • Anorexia is the third most common chronic disease among young people, after asthma and type 1 diabetes.
- • Young people between the ages of 15 and 24 with anorexia have 10 times the risk of dying compared to their same-aged peers.
- • Males represent 25% of individuals with anorexia nervosa, and they are at a higher risk of dying, in part due to the fact that they are often diagnosed later since many people assume males don’t have eating disorders.
- • Subclinical eating disordered behaviors (including binge eating, purging, laxative abuse, and fasting for weight loss) are nearly as common among males as they are among females.
- • An ongoing study in Minnesota has found incidence of anorexia increasing over the last 50 years only in females aged 15 to 24. Incidence remained stable in other age groups and in males.
- • Eating disorder symptoms are beginning earlier in both males and females, which agrees with both formal research and clinical reports.
Bennett, D., Sharpe, M., Freeman, C., & Carson, A. (2004). Anorexia nervosa among female secondary school students in Ghana. The British Journal of Psychiatry, 185(4), 312-317.Bulik CM, Sullivan PF, Tozzi F, Furberg H, Lichtenstein P, and Pedersen NL. (2006). Prevalence, heritability, and prospective risk factors for anorexia nervosa. Archives of General Psychiatry, 63(3):305-12. doi:10.1001/archpsyc.63.3.305.
Favaro A, Caregaro L, Tenconi E, Bosello R, and Santonastaso P. (2009). Time trends in age at onset of anorexia nervosa and bulimia nervosa. Journal of Clinical Psychiatry, 70(12):1715-21. doi: 10.4088/JCP.09m05176blu.
Hoek, H. W., & van Hoeken, D. (2003). Review of the prevalence and incidence of eating disorders. International Journal of Eating Disorders, 34(4), 383-396
Hudson, J., Hiripi, E., Pope, H., & Kessler, R. (2007) “The prevalence and correlates of eating disorders in the national comorbidity survey replication.” Biological Psychiatry, 61, 348–358.
Keski-Rahkonen A, Hoek HW, Susser ES, Linna MS, Sihvola E, Raevuori A, …, and Rissanen A. (2007). Epidemiology and course of anorexia nervosa in the community. American Journal of Psychiatry, 164(8):1259-65. doi: 10.1176/appi. ajp.2007.06081388.
Lai, K. Y. (2000). Anorexia nervosa in Chinese adolescents—does culture make a difference?. Journal of Adolescence, 23(5), 561-568.
Lucas AR, Crowson CS, O’Fallon WM, Melton LJ 3rd. (1999). The ups and downs of anorexia nervosa. International Journal of Eating Disorders, 26(4):397-405. DOI: 10.1002/(SICI)1098108X(199912)26:4<397::AID-EAT5>3.0.CO;2-0.
Mond, J.M., Mitchison, D., & Hay, P. (2014) “Prevalence and implications of eating disordered behavior in men” in Cohn, L., Lemberg, R. (2014) Current Findings on Males with Eating Disorders. Philadelphia, PA: Routledge.
Sabel, A., Rosen, E., & Mehler, P. (2014) “Severe anorexia nervosa in males: clinical presentations and medical treatment.” Eating Disorders: The Journal of Treatment and Prevention, 22-3, 209-220.
Stice, E. (2002). Risk and maintenance factors for eating pathology: A meta-analytic review. Psychological Bulletin, 128, 825-848.
Stice E & Bohon C. (2012). Eating Disorders. In Child and Adolescent Psychopathology, 2nd Edition, Theodore Beauchaine & Stephen Linshaw, eds. New York: Wiley.
Stice E, Marti CN, Shaw H, and Jaconis M. (2010). An 8-year longitudinal study of the natural history of threshold, subthreshold, and partial eating disorders from a community sample of adolescents. Journal of Abnormal Psychology, 118(3):587-97. doi: 10.1037/a0016481.
Wade, T. D., Keski-Rahkonen A., & Hudson J. (2011).Epidemiology of eating disorders. In M. Tsuang and M. Tohen (Eds.), Textbook in Psychiatric Epidemiology (3rd ed.) (pp. 343-360). New York: Wiley.