Iron in Diet

Overview & Functions

Iron is an essential mineral for humans because it is part of blood cells. About 30% of the iron in the human body is in storage to be readily available to replace any that is lost.

Iron is essential to the formation of hemoglobin and myoglobin, which carry oxygen in the blood and muscles. It also makes up part of many proteins and enzymes in the body.

Iron deficiency is the most common nutritional deficiency worldwide. Although full-blown anemia is rarely evident, partial deficiency is widespread.

Symptoms of decreased iron stores include general fatigue, shortness of breath, headache, irritability, and/or lethargy. 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 unusual signs of 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 stores include:

• Menstruating women (Women with heavy periods are particularly at risk.
• Pregnant and postpartum women -- extra iron is needed to meet the needs of the growing fetus and to make up for iron lost due to blood loss during childbirth
• Infants are born with iron stores that last about six months. An infant's additional iron needs are met by breast milk. A non-breast-fed infant's iron needs can be met with an iron supplement or iron-fortified infant formula. As babies move to solid foods, foods containing high amounts of iron should be selected to prevent the development of iron deficiency.
• Toddlers between 1 and 4 years of age are at risk for developing iron deficiency because of rapid growth and a lack of sufficient iron in their diets unless iron-fortified foods or a supplement is available. Because milk is a very poor source of iron, children who drink large quantities of milk at the expense of other foods may develop "milk anemia." Recommended milk intake is two to three cups per day for toddlers.
• Adolescents -- both boys and girls -- traditionally have been prone to anemia because of rapid growth rates, erratic eating habits, and concerns about body image.
• Long-distance runners -- demanding exertions may damage red blood cells
• Strict vegetarians (animal products contain the most bioavailable form of iron)
• People with bleeding lesions in their gastrointestinal tract.
• People with absorption problems in the gastrointestinal tract, such as celiac sprue or having had portions of the intestines removed, which may lead to low levels of iron.