I have a 16 year old son, he runs at the varsity level, for his high school, cross country, and track team. He is a distance runner. He recently had some blood tests done. His hemoglobin was 14.8 g/dL, hematocrit was 44.5 %, and ferritin was 23 ng/mL. I have been told by the team doctor that his ferritin is too low for an endurance athlete and that he should take iron supplements. My son's pediatrician says that he does not need the supplements. Can you offer some advice? Should he take the supplements? If yes, then how much?