Iron deficiency anemia is probably the most common nutritional deficiency in the world - it is estimated that at least 500 million people are affected.
In children, iron deficiency is usually the result of an inadequate iron intake and can affect their behavior and development.
In adults, iron deficiency is most
commonly caused by chronic blood loss, such as with heavy menstruation or
intestinal bleeding from peptic ulcers, cancer, or hemorrhoids.
FOOD HAS TWO FORMS OF IRON
Dietary iron is available in two
valence states, Fe2+ (ferrous) and Fe3+ (ferric). The
OXIDATION OF IRON
Iron ions undergo two important changes of oxidation state during digestion and absorption.
The first change occurs in the stomach where iron (Fe3+) is reduced to iron (Fe2+ ). This reduction is favored by the low pH. Reducing agents, such as ascorbic acid, assist this process. Reduction is important because iron (Fe2+) dissociates from ligands more easily than iron (Fe3+).
The second change occurs in the duodenum. The duodenum is bicarbonate-rich, and alkaline. In the alkaline environment heme is absorbed directly by the mucosal cells. Within the cells, the iron dissociates from it. Free iron (Fe2+) ions are oxidized to iron (Fe3+), which is taken up by the mucosal cells in substantial amounts under all circumstances of nutritional iron status.
Heme iron is more easily absorbed by the body than nonheme iron. However, heme iron can also promote the absorption of non-heme iron. Therefore, eating beef and beans, for example, is good for providing adequate absorption of both types of iron.
Vitamin C also promotes iron absorption. This is true for both heme and nonheme iron. It is, therefore, beneficial to consume citrus fruits or juices, which are high in vitamin C, with foods that contain iron. For example, a meal might include a lean steak (heme iron source), baked potato (nonheme iron source), broccoli (nonheme iron source), and an orange (vitamin C source) for a good iron intake. You may absorb twice as much iron with just 50 mg of vitamin C, the amount in 1/2 cup of strawberries, orange juice, or broccoli.
Eating DAIRY FOODS while taking IRON
may result in decreased iron effectiveness.
Phytic and tannic acids are two food
components that, when consumed in large amounts, prevent the absorption of iron.
Phytic acid is found in rye bread and other foods made from whole grains. Phytic
acid is also found in nonherbal teas. Tannic acid is found in commercial black
and pekoe teas, coffee, cola drinks, chocolate, and red wines. You absorb up to
40% less iron with coffee, and up to 70% less with tea.
HIGH IRON FOODS
High in iron: liver, beef, ham, brewer's yeast, legumes, lima beans, kidney beans, dark green leafy vegetables, dried fruits (apricots, peaches, raisins, prunes), sardines, potato skin, fortified cereals.
There are many different kinds of iron
supplements. However, iron supplements should only be taken when there is a true
deficiency of iron and only under medical supervision.
TOO MUCH IRON
Iron is stored in the body and large amounts can be toxic. The amount absorbed in the intestine is usually carefully regulated. However, people are usually advised to consult their doctors before taking iron supplements.
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