"We know very little about the mechanism behind body image distortion," said Bulik. "We do know that there is a substantial genetic component but we do not yet know how those genes work to result in the disorder."
Because there are so many physical and psychological factors involved in anorexia and other eating disorders, recovery can be difficult.
"Once someone starts down the slippery slope of starvation, it simply spins out of control," said Bulik. "Even if the person wants to recover, it becomes enormously hard to eat and restore weight. The fear and anxiety underlying anorexia nervosa become paralyzing to recovery."
Caro's long struggle with anorexia emphasizes how pervasive a disease it is.
"Anorexia nervosa is not a phase," said Bulik. "Anorexia nervosa is not a choice. It needs to be taken seriously because, as Isabelle Caro's death underscores, it is serious."