U.S. researchers have discovered that people with the eating disorder anorexia nervosa have excess levels of fat in their bone marrow. The disease, which mainly affects young women, leads to extremely low body weight and is attributed to an obsessive fear of weight gain.
For the study, doctors took MRI scans on the knees of 40 girls whose average age was 16. Half of the girls were healthy and half had anorexia. The researchers found that the girls with anorexia had higher fat content and less than half as much healthy red marrow in their knees. The difference was also found in the upper shinbone and lower thighbone.
Dr. Catherine Gordon, an endocrinologist and director of the Bone Health Program at Children’s Hospital Boston who led the study, said that, “Bone formation is very low in girls with anorexia, and that’s a particular problem, because they are growing adolescents who should be maximally forming bones.”
Earlier studies found that hormonal changes in people who are malnourished trigger the bone marrow’s stem cells to turn into fat cells rather than bone-forming cells. Researchers believe this could explain why people with anorexia lose bone mass and sometimes develop osteoporosis; however, further study is needed.
