What Is Iron Rich Food?

Iron is an essential mineral in the diet because it is necessary for the production of hemoglobin, which carries oxygen throughout the body in blood. People who do not consume enough iron can develop anemia, with symptoms such as fatigue, dizziness and shortness of breath. While iron supplementation may be recommended for those with anemia, it is generally not advised for others, as it is difficult to excrete excess supplemental iron from the body. For this reason, most people are advised to obtain the recommended amount through iron-rich foods instead of supplements.

Types of Iron

There are two types of iron--heme iron and nonheme iron. Heme iron is derived from animal sources. Animal foods that have hemoglobin stores, such as meat and fish, are sources of heme iron. This iron is absorbed more easily by the body than nonheme iron, which is found in plant foods and fortified products. According to the Office of Dietary Supplements, 15 to 35 percent of the heme iron ingested is absorbed by the body, while only 2 to 20 percent of ingested nonheme iron is absorbed.

Sources of Heme Iron

The recommended amount of iron for men and non-menstruating women is 8 milligrams per day, while the amount for menstruating women is 18 mg per day. Some of the best animal sources of iron are shellfish, with 3 oz. of clams providing 23.8 mg and 3 oz. of oysters providing 10.2 mg. Additionally, a 3.5 oz. serving of shrimp supplies 2.7 mg of iron. Red meat and dark poultry meat are also good sources, with 3 oz. of most beef cuts providing approximately 3 mg of iron, and 3.5 oz. of dark meat turkey providing 2.3 mg. Organ meats are also rich sources of iron, but they are also quite high in cholesterol.

Sources of Nonheme Iron

Beans are one of the best plant sources of iron. One half cup of lentils contains 3.3 mg, ½ cup of white beans contains 3.9 mg and ½ cup of kidney beans contains 2.6 mg. Soy is also an excellent source, with ½ cup of tofu containing 3.4 mg. Additional nonheme sources of iron include molasses, with 3.5 mg per tablespoon, and spinach, with 3.2 mg per ½ cup. Nonheme iron is also included in many fortified products such as cereal. While all of these plant sources contain iron, this iron may not be easily absorbed, and therefore easily used, by the body.

Factors that Increase Absorption

Two factors can increase the rate of nonheme iron absorption. First, when a nonheme source of iron is ingested, along with a heme source of iron, the rate of absorption increases. While this may work well for meat eaters, it is not an option for vegetarians Fortunately, another factor that can increase the absorption of iron is ingesting it with vitamin C. For instance, a glass of vitamin C-rich orange juice can be combined with a meal of beans to increase the amount of iron that the body could absorb from the beans.

Factors that Decrease Absorption

While there are factors that increase iron absorption, there are also some that inhibit iron absorption. Tannins, which are present in tea, and oxalates, present in some leafy vegetables such as spinach, can both reduce the amount of iron absorbed from food. Calcium, phosphates and some prescription medicines can also decrease iron absorption.