Iron In Diet
Iron is a trace mineral and an essential nutrient. Iron is found in small amounts in every cell of the body. The body stores iron mainly in the liver, spleen, and bone marrow. The body needs only small amounts, and iron is widely available in many foods.
What food source is the nutrient found in?
Iron can be found in both animals and plants in two forms. Heme iron is found in meat, fish, and poultry. The best source is lean red meat. This is the easiest form of iron for the body to use and absorb.
Non-heme iron is found in plant foods. The body has a harder time absorbing iron from plants. Foods rich in vitamin C, such as citrus fruits, strawberries, and broccoli, improve iron absorption, especially non-heme iron.
Different foods have different amounts of iron. The following are examples of animal foods that contain heme iron:
- liver and braised beef (3.5 oz. serving) = 6.8 mg iron
- broiled short loin or T-bone steak (3.5 oz. serving) = 3.2 mg iron
- well-done baked ground beef (3.5 oz. serving) = 3.0 mg iron
- cooked shrimp (3 oz. serving or 15 large shrimp) = 2.6 mg iron
- chicken, dark meat, roasted with skin (3.5 oz. serving) = 1.4 mg iron
- turkey, light meat, roasted without skin (3.5 oz. serving) = 1.4 mg iron
Some good sources of plant iron, or non-heme iron, are as follows:
- spinach, boiled (1/2 cup) = 3.2 mg iron
- kidney beans, red, boiled (1 cup) = 5.2 mg iron
- potato, baked with skin (1 large) = 2.7 mg iron
- noodles, egg, enriched, cooked (1 cup) = 2.5 mg iron
- rice, white, enriched, cooked (1 cup) = 1.9 mg iron
- rice, long grain, brown, cooked (1 cup) = 0.82 mg iron
- raisins, seedless (2/3 cup) = 2.1 mg iron
- broccoli, boiled (1/2 cup) = 0.66 mg iron
- egg, boiled, hard/soft (1 large) = 0.59 mg iron
How does the nutrient affect the body?
Iron plays an important part in keeping people healthy. Iron is vital to how cells make energy. It is an essential part of hemoglobin, which helps carry oxygen in blood from the lungs to every body cell. It is needed to make new cells, proteins, hormones, and substances necessary for nerve functioning. Iron helps protect the body from infections because it is a part of an enzyme in the immune system.
Iron also helps to convert beta-carotene
to vitamin A. Vitamin A helps produce tissues that hold the body together.
Even though we only need a small amount of iron in the body, iron deficiency is the most common nutrient deficiency in the world. The consequence of iron deficiency in the boyd is anemia, that is, a low red blood cell count. Its symptoms include:
- difficulty concentrating
- shortness of breath
Women have iron deficiency anemia more often than men, because blood is lost each month during menstruation. Vegetarians are at higher risk for anemia. Children between the ages of 1 and 4 years old and adolescents who may not get enough iron from their diets are also at risk.
In addition, premature babies are at a very high risk because they run out of iron stores earlier than full term newborns. Babies who ingest too much milk (>35 ounces per 24 hrs) are also at risk, as are babies exposed to cows milk before one year of age, or those who are fed low-iron formulas.
To improve iron in the diet, the following may help:
- Consume foods rich in heme iron, including lean red meat and dark poultry.
- Eat dark green, iron-rich vegetables with meat, poultry, or seafood. The iron in the animal protein enhances absorption of the iron in the vegetables.
- Include foods high in vitamin C at each meal. This will enhance the body's absorption of iron, especially the non-heme iron, which is harder to absorb.
- Eat enriched or fortified grain, cereal, and pasta products that have iron added to them.
- Use iron cooking pans, for example, cast-iron skillets.
- Include an animal protein when eating grains, cereal, or pasta to increase the absorption of non-heme iron.
- Avoid drinking tea when eating iron-rich foods. The tannic acid in tea reduces iron absorption by about 50%. Coffee also reduces iron absorption but not as much.
The amount of iron needed for good health varies. Following are the Recommended Daily Allowances
- 11 mg for children from 7 to 12 months old
- 7 mg for children from 1 to 3 years old
- 10 mg for children from 4 to 8 years old
- 8 mg for boys and girls from 9 to 13 years old
- 11 mg for boys 14 to 18 years old
- 15 mg for girls 14 to 18 years old
- 8 mg for adult men 19 years and older
- 18 mg for adult women 19 to 50 years old
- 8 mg for adult women 51 years and older
- 27 mg for pregnant women
- 25 mg for adolescent women 14 to 18 years old who are breastfeeding
- 27 mg for women 19 years and older who are breastfeeding
Iron supplements are available for individuals who are not getting enough iron from their diet. When taking iron supplements, it is important to consider the following guidelines:
- Iron is best taken on an empty stomach, with water or fruit juice, one to two hours after a meal.
- If iron causes stomach upset, the iron supplement can be taken with food or right after a meal.
- Antacids may make iron supplements less effective, so iron should be taken at least one to two hours before or after antacids.
- Certain foods interfere with iron absorption and should be avoided one to two hours after or before an iron supplement is taken. These foods include eggs, milk, cheese, tea, coffee, and whole grain bread.
- Iron and calcium supplements should not be taken together.
- There are some interactions between iron and certain medications, such as some antibiotics. Individuals taking iron supplements should let their healthcare professionals know this when new medications are prescribed.
- Iron can worsen certain medical conditions, such as stomach ulcers. It's important to discuss iron supplements with the healthcare professional.
It is hard to get too much iron just from food. However, it is possible to get too much iron if vitamin and mineral supplements are used. Too much iron can be poisonous, especially for children. Vitamins with iron, including chewable vitamins made for children, should be kept out of the reach of children.
Symptoms of iron toxicity include the following:
- loss of appetite
- shortness of breath
- weight loss
Somer, E., MA, RD.&Health Media of America. (1995). The Essential Guide To Vitamins and Minerals (2nd ed.). New York: HarperCollins Publishers, Inc.
Duyff, R., MS, RD, CFCS. (1996). The American Dietetic Association's Complete Food&Nutrition Guide. Minnesota: Chronimed Publishing.
Murray, M., ND. (1996). Encyclopedia of Nutritional Supplements. California: Prima Publishing.