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.
Although the disorder most frequently begins during adolescence, an increasing number of children and older adults are also being diagnosed with anorexia. You cannot tell if a person is struggling with anorexia by looking at them. A person does not need to be emaciated or underweight to be struggling. 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.
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.

In anorexia nervosa’s cycle of self-starvation, the body is denied the essential nutrients it needs to function normally. Thus, the body is forced to slow down all of its processes to conserve energy, resulting in serious medical consequences.

The body is generally resilient at coping with the stress of eating disordered behaviors, and laboratory tests can generally appear perfect even as someone is at high risk of death. Electrolyte imbalances can kill without warning; so can cardiac arrest. Therefore, it’s incredibly important to understand the many ways that eating disorders affect the body.