Woobie, if your doctor is just going by labs then please consider seeing a new doc.
Normal lab results are very common on someone who is very underweight. I just mine tested again in December and they were also right on the nose too
(normal). My nails are still purple and I still get cold but it's not really cold outside (71 degrees).
My hair is still falling out etc..
Here are some links about people with normal labs and who are underweight: fishyvb.something-fishy.org/archive/index.
"..blood values can be normal and cannot, therefore, be used as a proof of adequate nutrition." www.bulimia.com/client/client_pages/exerpt
"..normal lab results despite clear-cut anorexia – occurs so often is that the body works very hard and very effectively to compensate for starvation. The ups and downs of human evolution have ensured that the body is well-adapted to surviving famine. Usually labs will stay normal until the patient is in very serious medical trouble, and then things go downhill so fast.." www.eatingdisordersblogs.com/nutrition/200