Transferrin is a protein in the blood that plays a crucial role in iron transport. It binds to iron ions and carries them to various tissues in the body, ensuring that cells receive the iron they need for essential functions, such as producing red blood cells and supporting metabolism. When the body has enough iron, transferrin levels can decrease, while low levels of iron can lead to increased transferrin production. This regulation helps maintain proper iron balance, which is vital for overall health and is closely related to conditions like anemia and hemochromatosis.