He has a Thyroid problem which means that his metabolism is a lot faster than normal people. This means that he will have spells or days upon days of boundless energy where he wont be able to sleep or relax followed by crashes of complete energy deficiency, faintness, lethargy or anaemia.
It basically means that his body is burning itself out too fast. It's why he's so skinny, his body is like a firework burning at both ends. In short it means he's probably going to die young.
From Wikipedia:
If there is too much thyroid hormone, every function of the body tends to speed up. Therefore, some of the symptoms of hyperthyroidism are nervousness, irritability, increased perspiration, heart racing, hand tremors, anxiety, difficulty sleeping, thinning of the skin, fine brittle hair, and muscular weakness—especially in the upper arms and thighs. More frequent bowel movements may occur, but diarrhea is uncommon. Weight loss, sometimes significant, despite a good appetite may occur, vomiting, and, for women, menstrual flow may lighten and menstrual periods may occur less often.[6] Thyroid hormone is critical to normal function of cells.
Another interesting symptom is " feminization" a medical condition which makes the subject more feminine. Sound familiar? XD
