Iron is a mineral concentrate in the blood which is present in every living cell. All iron exists in the body combined with protein.
The major function of iron is to combine with protein and copper in making hemoglobin, the coloring matter of red blood cells. Hemoglobin transports oxygen in the blood from the lungs to the tissues, which need oxygen to maintain the basic life functions. Thus iron builds up the quality of the blood and increases resistance to stress and disease. Iron is also necessary for the formation of myoglobin, which is pound only in muscle tissue. Myoglobin is also a trans-3rter of oxygen; it supplies oxygen to the muscle cells use in the chemical reaction that results in muscle contraction.
Iron is present in enzymes that promote protein metabolism, and it works with other nutrients to improve respiratory action. Calcium and copper must present for iron to function properly. I The best source of dietary iron is liver, with oysters, lean meat, and tongue as second choices, green vegetables, whole grains, dried fruits, le-s, and molasses are rich in iron.
The body can utilize either -ferric or ferrous iron, but ace indicates that naturally occurring ferrous iron more efficiently and that most iron is reduced 3US iron before being absorbed. It is absorbed in regulated amounts into the blood and bone marrow. Ninety percent of the iron ingested never reaches the blood and remains unabsorbed. Absorption occurs in the upper part of the small Iron is usually absorbed within 4 hours ingestion; from 2 to 4 percent of the iron found is used by the body. It is primarily stored in the liver, spleen, bone marrow, and blood.
The iron in the body is normally used efficiently. It is neither used up nor destroyed, but it is conserved to be used repeatedly. Only very small amounts are normally excreted from the body. Iron is excreted in small amounts in the urine, feces, during menstruation, and through perspiration and exfoliation of the skin.
There are many factors that influence the absorption of iron. Ascorbic acid enhances absorption by helping reduce ferric to ferrous iron. The iron found in animal protein is more readily absorbed than the iron in vegetables. The degree of gastric acidity regulates the solubility and availability of the iron in food.
The balance of calcium, phosphorus, and iron is very important. Excess phosphorus hinders iron absorption, although if calcium is present in sufficient amounts, it will combine with the phosphates and free the iron for use. In addition, the lack of hydrochloric acid; the administration of alkalis; a high intake of cellulose, coffee, and tea; the presence of insoluble iron complexes (phytates, oxalates, and phosphates); and increased intestinal mobility all interfere with iron absorption.
The National Research Council suggests a daily iron intake of 18 milligrams for women and 10 milligrams for men. The need for iron increases during menstruation, hemorrhage, periods of rapid growth, or whenever there is a loss of blood. Additional iron is required during pregnancy, when the developing fetus builds up its own reserve supply of iron in the liver.
A toxic level of iron may occur in an individual due to a genetic error of metabolism, due to blood transfusion, due to a prolonged oral intake of iron, in persons who consume large amounts of red wine containing iron, and in those addicted to certain iron tonics.
Excessive deposits of iron may result from such conditions as cirrhosis of the liver, diabetes, pancreas insufficiency, the presence of other diseases, hemolytic or aplastic anemia, early hepatitis, and a vegetarian diet.
Too much iron, accumulating over the years, occurs often in older men. Iron overload can result in siderosis, damage to the heart, liver, and pancreas. Studies have shown that arthritic patients insufficiently metab-
olize iron, possibly resulting in deposition of the mineral in the joints.
These diseases caused by iron toxicity are due to the inability of the digestive tract to eliminate excess iron. Iron deposited in body tissues eventually turns the skin a grayish color. Symptoms of iron overload include headache, shortness of breath, fatigue, dizziness, and loss of weight.
Deficiency Effects and Symptoms
The most common deficiency of iron is iron-deficiency anemia (hypochromic anemia), in which the amount of hemoglobin in the red blood cells is reduced and the cells consequently become smaller. As in other forms of anemia, iron-deficiency anemia reduces the oxygen-carrying capacity of the blood, resulting in pale skin and abnormal fatigue. Symptoms of anemia may include constipation, lusterless, brittle nails, and difficult breathing.
A deficiency of B6 and zinc can cause blood disorders that mimic an iron deficiency. Measuring serum iron, not the hemoglobin, is the most efficient way to diagnose an iron deficiency.
Hemorrhagic anemia, marked by internal hemor-rhaging, may not be detected for some time, especially when associated with the bleeding that may occur in peptic ulcers. Excessive donation of blood may cause this type of anemia.
Infections and peptic ulcers may also lead to anemia.
Beneficial Effect on Ailments
When iron-deficiency anemia, with its symptoms of pallor, easy fatigue, and decreased resistance to disease, is diagnosed, a diet high in iron-rich foods with a concurrent intake of vitamin C will speed up the restoration of hemoglobin levels to normal. Iron is the most important mineral for the prevention of anemia during menstruation. Iron may also be beneficial in the treatment of leukemia and colitis
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