Iron is a very important mineral to our health because it transports oxygen from the lungs throughout the cells of the body. Iron carries oxygen on a blood component called hemoglobin. Having too little iron in the blood to bring the oxygen to the body cells results in a condition called anemia.
Iron Deficiency Anemia
Iron deficiency is the most common nutritional deficiency in the United States, according to the Centers for Disease Control and Prevention. The causes for dietary-induced iron deficiency include increased needs during growth, such as in children or pregnancy, or from decreased intake or absorption of the mineral from foods that are eaten.
Heme vs Non-Heme Iron
There are two types of iron in the diet. Heme iron is present in animal products, such as meat, poultry and fish. Non-heme iron is found in plant foods and foods that are fortified with minerals, such as breakfast cereals. Heme iron is absorbed two to three times more efficiently by the body than non-heme iron, but there are many factors that can affect the absorption of iron in the body.
Heme sources of iron eaten at the same time as non-heme sources can improve the absorption of the mineral. For example, ground beef in a pot of chili can increase the iron absorption from the kidney beans in the dish. The foods do not have to be mixed – eating a leafy green vegetable as a side to a meat or poultry entrée can also improve the absorption of iron.
Improving Iron Absorption
Foods that contain vitamin C can help absorb non-heme iron as well. High vitamin C foods include citrus fruits such as oranges and lemons, broccoli and potatoes. Orange juice with breakfast can improve the absorption of iron from the cereal.
Foods that Interfere with Iron
Some dietary substances actually interfere with iron absorption, both heme and non-heme. Phytates, polyphenols and calcium inhibit iron from being absorbed in the intestine. Foods that should be consumed separately from iron-containing foods include tea, coffee and dairy products such as milk and cheese. Whole grains and high fiber foods, while very healthy for the body, can also interfere with iron absorption. If dietary iron is a concern, planning may be needed to consume these foods separately from high-iron foods.
Some cooking methods are thought to help iron content of foods as well. Cooking foods in an iron pot for 20 minutes can increase the iron by nine times. This method works best for acidic foods, such as tomatoes.
Vegetarians receive most of their dietary iron as non-heme sources. However, this should not be a concern if meals are well planned to include a variety of nutrient sources and care is taken to use methods of increasing iron absorption, such as ensuring a vitamin C source with meals.
Best Iron Sources
The best foods sources of iron include red meat (beef and lamb), dark meat chicken and duck, shellfish such as clams and oysters, dried beans such as soybeans, lentils, and kidney beans, and dried fruits such as raisins and prunes.