The lowest accepted ferritin level to be able to donate blood is 12 nanograms per milliliter for men and women, according to MedicineNet. These standards may vary slightly between laboratories.
Ferritin is an important protein in the body that is responsible for the storage of iron, explains MedicineNet. Measuring levels of ferritin in the body can indirectly measure iron levels as well. Low levels of ferritin can indicate anemia, while high levels can indicate problems with the body’s iron storage capabilities. When anemia occurs because of low iron levels, the body cannot produce high enough levels of hemoglobin, which allows red blood cells to carry oxygen. Symptoms of serious anemia may include fatigue, dizziness and an elevated heart rate, while mild anemia may show no symptoms at all.