Iron
Iron is most available to the body when added to amino acids – iron in this form is ten to fifteen times more digestible than than it is as an element. Iron is also found in meat, for example steak. Iron provided by diet supplements is in the form of a chemical, such as Iron(II) sulfate, which is cheap and is absorbed well. The body will not take up more iron than it needs, and it usually needs very little. The iron in red blood cells is recycled by a system which breaks down old cells. Loss of blood by injury or parasite infection may be more serious.