Iron is a mineral that plays an important role in oxygen delivery to tissues. It is necessary for the production of hemoglobin in red blood cells, and is involved in the production of ATP (the basic unit of energy in the body). It is also essential for the regulation of cell growth and differentiation.
There are two forms of dietary iron: heme and nonheme. Heme iron is derived from hemoglobin, the protein in red blood cells that delivers oxygen to cells. Heme iron is found in animal foods that originally contained hemoglobin, such as red meats, fish, and poultry. Iron in plant foods such as lentils and beans is arranged in a chemical structure called nonheme iron.