Red blood cells and hemoglobin

Anemia is a condition characterized by a lack of enough healthy red blood cells to transport an adequate level of oxygen to the body’s tissues, which can cause severe damage to them.

Blood carries oxygen and nutrients to living cells and removes their waste products. It also releases immune cells to fight infection and contains platelets that can form a plug in a damaged blood vessel to prevent blood loss.

Anemia is technically defined as a decreased number of red blood cells, as a decreased concentration of hemoglobin in the blood, or as a lower than normal hematocrit value.