Iron is a mineral that is found in every living cell. Iron
exists in two forms—heme and nonheme. Heme iron is part of the
hemoglobin and myoglobin molecules in animal tissues. About 40%
of the iron in meat is in the heme form. Nonheme iron comes from
animal tissues other than hemoglobin and myoglobin and from
plant tissues. It is found in meats, eggs, milk, vegetables,
grains, and other plant foods. The body absorbs heme iron much
more efficiently than nonheme iron. Much of the iron in our diet
comes from foods, such as breads and cereals that are fortified
with this mineral. Worldwide, iron deficiency anemia is the most
common form of malnutrition. Iron's functions include: - In
hemoglobin, carrying oxygen to cells throughout the body - In
myoglobin, holding oxygen within the cells, especially heart and
skeletal muscle cells - Forming collagen, which is the major
protein that makes up connective tissue, cartilage, and bone -
Helping fight infection by synthesizing certain enzymes needed
for immune function -