Iron deficiency Iron-deficient erythropoiesis (IDE). Untreated iron deficiency can lead to iron deficiency anemia, a common type of anemia. Anemia is a condition characterized by inadequate red blood cells (erythrocytes) or hemoglobin. Iron deficiency anemia occurs when the body lacks sufficient amounts of iron, resulting in reduced production of the protein hemoglobin. Hemoglobin binds to oxygen, thus enabling red blood cells to supply oxygenated blood throughout the body. Children, pre-menopausal women (women of child-bearing age) and people with poor diet are most susceptible to the disease. Most cases of iron deficiency anemia are mild, but if not treated can cause problems like
Effect of spaceflight on the human body enough oxygen to the brain without the astronaut's fainting or becoming dizzy. "Under the effects of the earth's gravity, blood and other body fluids are pulled towards the lower body. When gravity is taken away or reduced during space exploration, the blood tends to collect in the upper body instead, resulting in facial edema and other unwelcome side effects. Upon return to earth, the blood begins to pool in the lower extremities again, resulting in orthostatic hypotension." In 2013 NASA published a study that found changes to the eyes and eyesight of monkeys with spaceflights longer than 6 months. Noted