Iron supplements. Chelated iron has been treated to bind it to an amino acid, supposedly to make it more like that occurring naturally in foods. It allegedly is more easily absorbed through cell walls. Ferrous sulfate is the most common & cheapest iron supplement but may not be well tolerated. Ferrous fumarate is better absorbed, but heme iron polypeptide is well tolerated & absorbed. Vitamin c enhances iron uptake.
Iron. Ferrous sulfate is also known as iron. You can use this as a supplement if your iron level is low- as a treatment for iron deficiency. Iron chelating agent- on the other hand- is used to bind the iron in your blood and then remove it from your body. This will be used if your iron level is too muc/highh- for instance in the setting where you received multiple blood transfusion.