Iron is quite abundant in meat, poultry, and fish. These foods contain heme iron. Plants and vegetables contain non-heme iron, but this is not as good a source of iron as foods that have heme iron. Heme iron absorbs more efficiently from the gastrointestinal tract than does non-heme iron. However, if one includes foods that are rich in vitamin C, non-heme iron will absorb better than it will without that vitamin present.
Iron and diet
The best sources of iron are foods that contain a great deal of fat such as red meat. People who follow low-fat diets for a long time may become deficient in iron if they do not obtain sufficient amounts of it from other foods. Nevertheless, most dietary iron is non-heme, and this is the type of iron that is also present in iron-rich or fortified foods.
Certain foods that a person consumes with a meal will influence how much non-heme iron he or she absorbs, but those other foods will not affect the absorption of heme iron. Obviously vegetarian diets will be low in heme iron, but a strategic meal plan will enhance the amount of iron these clients receive every day.
Tannins, which are in tea, may impair the absorption of non-heme iron. Moreover, legumes and whole grains which may contain calcium, phytates, and polyphenols can hinder non-heme iron absorption. It is also true that the absorption of iron is inversely proportional to the amount of body stores of iron. In other words, the less the body stores of iron, the greater the absorption of iron through the gastrointestinal system.
Healthy adults absorb 10 to 15 per cent of the iron that they consume in their diet. A diet high in fiber may lessen the absorption of iron even more. Vitamin A also influences the availability of iron in the body because it mobilizes iron from the storage sites. The deficiency of vitamin A is not common in the United States, but in countries where it does exist, cases of iron deficiency result.
The Food and Drug Administration requires that all food labels in the United States indicate the percent daily value of iron per serving of the product. This enables consumers to follow their own adherence to the Recommended Daily Allowance which is the average daily intake of a certain nutrient necessary to meet the requirements of most healthy people of all age groups.
Adolescent girls and women of childbearing age have additional iron requirements since they menstruate. Neither women who have completed the menopause nor adult men require as much iron as girls and women who menstruate. Women who take oral birth control pills, however, may have less risk of iron deficiency than women who menstruate and who do not take contraceptive hormonal therapy.
Women who take oral contraceptives tend to lose less blood with menstruation than women who do not take birth control.
The absorption of iron is not as good when one consumes low nutrient density foods such as desserts and sodas which contain sugar. There is also an association of iron deficiency with pica or geophagia which is the oral intake of dirt, clay, starch, and excessive amounts of ice. It is not clear whether the iron deficiency is the result of pica or pica the consequence of iron deficiency.
Children who acquire lead in their bloodstream may become anemic because this element interferes with the body’s ability to make hemoglobin. They may become toxic with lead through inhalation of lead dust, intake of water which contains lead, or oral consumption of paint or soil.
Patients with kidney failure tend to become anemic. This may be anemia of chronic disease; however, it is important to note that the kidney makes a hormone, erythropoietin, which enables the body to produce red blood cells. When the kidneys fail, whether because of high blood pressure, diabetes mellitus, or other medical conditions, the production of erythropoietin and red blood cells will decline.
Excessive iron intake
The seriousness of iron deficiency should not prompt anyone to take supplementation of this mineral without a physician’s recommendation. In fact, excessive amounts of iron intake can lead to damage to internal organs or death. People who take iron supplements should keep them out of reach of children as childhood deaths have occurred from an overdose of it.