Iron is an essential microelement which cannot be produced by our body; therefore it has to be supplied externally through nutrition. However, the absorption and bioavailability of iron is extremely bad; with food (e.g. meat, liver, egg, sorrel, spinach, legumes, nuts, etc.) only a fraction of the iron intake gets into the blood. Accordingly, it is important to supply the iron quantity necessary for the operation of our body from other, external sources.