Food contains two types of iron: heme iron and non heme iron. Heme iron is a part of hemoglobin and myoglobin, so it is found only in animal tissue.
Meat, fish, and poultry contain about 40 percent heme iron. The other 60% is non-heme iron. Non-heme iron is found primarily in plant foods such nuts, fruits, vegetables, grain and tofu.
Heme iron is much more bioavailable than non-heme iron.
Heme iron exists mainly in ferrous form. Ferrous form of iron is easily absorbed. It is assumed that 25% of the consumed iron can be absorbed in adult. If heme iron is cooked for a long time, it can be converted to non-heme and bioavailability will be affected.
On average, heme iron represents about 10% of the iron a person consumes in a day. Even though heme iron accounts for only a small proportion of the intake, it is so well absorbed that it contributes significant iron.
Efficiency of heme iron absorption is approximately two or three times greater than that of non-heme iron. Many plant based foods such as legumes and cereals contain high levels of phytates, which can inhibit dietary non heme iron absorption.
Dietary of heme iron
