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Alternative names
Diet - ironDefinition Return to top
Iron is a trace mineral found in every cell of the body. Iron is an essential mineral for humans because it is part of blood cells.
Function Return to top
Iron is part of hemoglobin in red blood cells and myoglobin in muscles. The role of both of these molecules is to carry oxygen. Iron also makes up part of many proteins and enzymes in the body.
Food Sources Return to top
The best sources of iron include:
Reasonable amounts of iron are also found in lamb, pork, and shellfish.
Iron from vegetables, fruits, grains, and supplements is harder for the body to absorb. These sources include:
If you mix some lean meat, fish, or poultry with beans or dark leafy greens at a meal, you can improve absorption of vegetable sources of iron up to three times. Foods rich in vitamin C also increase iron absorption.
Some foods reduce iron absorption. For example, commercial black or pekoe teas contain substances that bind to iron so it cannot be used by the body.
Side Effects Return to top
The human body stores some iron to replace any that is lost. However, continual low iron can lead to a type of anemia. (See iron deficiency anemia.) This is the most common nutritional deficiency worldwide.
The symptoms of low iron include lack of energy, shortness of breath, headache, irritability, dizziness, or weight loss. Other symptoms include pica (the development of an appetite for unusual substances such as paper or clay products) and pacophagia (the development of an appetite for ice).
If you have constant tiredness, see your health care provider. There are many causes of such symptoms, and simply taking an iron supplement may not be enough.
Those at risk for low iron include:
TOO MUCH IRON
It is unlikely that a person would take iron at toxic (too high) levels. However, children can sometimes develop iron toxicity by taking too many iron supplements. Symptoms include the following:
Hemochromatosis is a genetic disorder that affects the regulation of iron absorption. Treatment consists of a low-iron diet, no iron supplements, and phlebotomy (blood removal) on a regular basis.
Excess storage of iron in the body is known as hemosiderosis. The high iron stores come from eating excessive iron supplements or from receiving frequent blood transfusions, not from increased iron intake in the diet.
Recommendations Return to top
According to USDA recommendations, the allowances of dietary iron intake are as follows:
Any male or postmenopausal female with iron deficiency should be evaluated by a health care provider to rule out whether the problem may be due to a more serious gastrointestinal cause, such as ulcers, polyps, or tumors.
Update Date: 1/19/2003 Updated by: Steven Angelo, M.D., Assistant Professor of Medicine, Yale School of Medicine, New Haven, CT. Review provided by VeriMed Healthcare Network.
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Page last updated: 28 October 2004 |