Anorexia and Bone Loss: An Overview
Approximately 1 percent of adolescent girls develop
anorexia nervosa, an
eating disorder characterized by an irrational fear of weight gain. The condition usually begins around the time of puberty and is associated with restricted eating and extreme weight loss.
Anorexia is a mental disorder with significant physical consequences. Affected individuals typically experience an absence of menstrual periods and other health problems that negatively affect
bone density.
Causes of Bone Loss in Anorexia
Both nutritional and endocrine factors set the stage for bone loss in people with anorexia. One of the most significant factors is estrogen deprivation. Low body weight causes the body to stop producing estrogen. This disruption in the menstrual cycle, known as amenorrhea, is associated with estrogen levels similar to those found in postmenopausal women. Significant losses in bone density typically occur.
Elevated glucocorticoid levels also contribute to low bone density in people with anorexia. Sufferers tend to have excessive amounts of the glucocorticoid cortisol, which is known to trigger bone loss. Other factors, such as a decrease in the production of growth hormone and growth factors, low body weight (apart from estrogen loss),
calcium deficiency, and malnutrition have also been proposed as possible causes of bone loss in females with the disorder.
