Now here’s one I hadn’t heard before. Researchers recently discovered that anorexics have extra fat -- in their bone marrow. The results came from radiologists at Children’s Hospital Boston, who used MRI to image the knees of 20 girls with anorexia and 20 healthy girls of the same age.
MRI of a control patient's knee
MRI of an anorexic patient's knee
It turned out that patients with anorexia had markedly increased fat content--visualized as "yellow marrow"--and less than half as much healthy red marrow in their knees.
What does this mean?
No one knows. The researchers are guessing that fatty knees has something to do with the body's attempt to store energy and preserve warmth in the face of starvation. Researchers are also bantering about the hormonal consequences of malnutrition. Hormonal changes can prompt stem cells in the bone to mature into fat cells (adipocytes) rather than bone-forming cells (osteoblasts). This altered-path phenomenon may explain why people with anorexia nervosa lose bone mass, sometimes leading to osteoporosis and fractures.
The finding is provocative and worthy of further study.
“It’s counter-intuitive that an emaciated young woman with almost no subcutaneous fat would be storing fat in her marrow," says endocrinologist Catherine Gordon, MD, MSc, director of the Bone Health Program at Children's and the study's senior investigator.
But perhaps that's nature way of keeping the body alive during times of famine. And something we just really don't understand very well.
Kudos to nature and human resilience. But how sad that such an insidious disease must continually test nature’s limits. Let’s hope the research brings news avenues for therapy. And better yet, more maneuvers to outwit anorexia.

