Blood is the red fluid that circulates through our bodies in veins and arteries. It acts as the body's transport system and plays a major role in defense against infection. Blood cannot be manufactured and must come from donors to help patients in need. Donors are encouraged to maintain healthy iron levels before donating blood and are monitored for at least 15 minutes after donating. Donating blood helps ensure a safe and reliable blood supply for transfusions and can help save lives.