Anemia occurs when you have less than the normal number of red blood cells in your blood or when the red blood cells in your blood don't have enough hemoglobin. Hemoglobin is a protein that gives the red color to your blood. Its main job is to carry oxygen from your lungs to all parts of your body. If you have anemia, your blood does not carry enough oxygen to all the parts of your body. Without oxygen, your organs and tissues cannot work as well as they should. Since there are many types and causes of anemia, The most frequent causes: Iron deficiency, B12 deficiency, and the bone marrow�s ability to produce red blood cells.Complete Blood Count (CBC), Iron, TIBC, UIBC, % Transferrin Saturation, Ferritin