A young, male patient, only 20, came into the clinic for a yearly general exam but complained of being more tired than usual lately. After performing a physical exam, taking blood and checking his cholesterol, we were shocked to find that his cholesterol was well above average. More surprising is that this patient is actually underweight. It's my concern that there is a greater underlying concern than an early onset dyslipidemia, especially since he claims he eats healthily. What would you suggest testing for, and have you run across this in your patients before?