Iron is an essential part of hemoglobin, the protein substance which enables red blood cells to carry oxygen through the body.1,† Without oxygen, cells cannot function properly which can lead to fatigue and a lack of energy. Nature Made Iron 65 mg helps individuals lacking in iron, meet their nutrient needs for this essential mineral.† 1 in 10 US adult premenopausal women (ages 15 - 49yrs) are deficient in iron.* Each tablet contains 65 mg Elemental Iron (Equivalent to 325 mg of Ferrous Sulfate Heptahydrate) Vital for red blood cell formation† #1 Pharmacist Recommended Vitamin and Supplement Brand** Equivalent to 325 mg. Ferrous Sulfate Vital For Red Blood Cell Formation For Iron Deficiency Take 1 Tablet Daily With Water and a Meal