They may permanently stunt their growth and increase their risk of developing the bone-thinning disease osteoporosis, which usually is associated with older women and men. Girls may delay the start of their menstrual periods or miss periods if menstruation has already begun. We tend to think of eating disorders as a recent phenomena fueled by images of rail-thin models and actors. But the Greeks and Romans wrote about eating disorders, and some experts date them as far back as the 12th century. People whose parents or siblings have eating disorders are more likely to be diagnosed with them, and identical twins are more likely to both be diagnosed than non-identical twins.
Biology can help set the stage.
At puberty, a girl may correctly sense that she is eating more because her body needs a certain amount of fat to mature sexually. Biochemical studies offer some clues that may explain a starving girl can ignore the skeletal figure in the mirror. Researchers have found that the brains of some people with eating disorders have abnormal levels of hormones and neurotransmitters, although it is not clear whether these imbalances arise before or after an eating disorder occurs. Once established, these chemical imbalances may play a role in the disturbed perceptions and moods that can sustain abnormal eating patterns. These imbalances may persist for a while even after weight is restored.