What does having a deficiency in iron mean for the body?

Iron: Iron is a component of many enzymes and chemical structures in the body. Most importantly it is a component of hemoglobin which the oxygen carrying molecule in a red blood cell. Without enough iron, not enough red blood cells can be produced and you will develop iron deficiency anemia.

Find out why: Iron deficiency depletes myoglobin and cytochromes as well as red blood cells. The key is to find out why the person is iron deficient. Bad diet / Vegetarian who does not supplement? Gut cancer? Heavy monthly loss?