Anemia

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Alternative Names

Dietary Factors

Iron found in foods is either in the form of heme or non-heme iron:

• Heme Iron. Foods containing heme iron are the best for increasing or maintaining healthy iron levels. Such foods include (in decreasing order of iron-richness) clams, oysters, organ meats, beef, pork, poultry, and fish.
• Non-Heme Iron. Non-heme iron is less well absorbed. About 60% of the iron in meat is non-heme (although meat itself helps absorb non-heme iron). Eggs, dairy products, and iron-containing vegetables have only the non-heme form. Such vegetable products include dried beans and peas, iron-fortified cereals, bread, and pasta products, dark green leafy vegetables (chard, spinach, mustard greens, kale), dried fruits, nuts, and seeds.

The absorption of non-heme iron often depends on the food balances in meals. The following are foods and cooking methods that enhance absorption of iron.

• Meat and fish not only contain heme iron -- the best form for maintaining stores -- but they also help absorb non-heme iron.
• Increasing intake of vitamin-C rich foods, such as orange juice, may enhance absorption of non-heme iron, although it is not clear if mixed on their effectiveness in improving iron stores in iron-deficient people. In any case, vitamin-C rich foods are healthy and include broccoli, cabbage, citrus fruits, melon, tomatoes, and strawberries. (Taking vitamin C supplements does not appear to have any significant effect on iron stores.)
• Riboflavin (vitamin B2) may help enhance the response of hemoglobin to iron. Food sources include dairy products, liver, and dried fortified cereals.
• Cooking methods can enhance iron stores. Cooking in cast iron pans and skillets is well-known to increase the iron content of food. According to one study, boiling, steaming, or stir-frying in utensils composed of any material significantly increased the release of non-heme iron stored in vegetables.

Certain nutrients impede the body's absorption of dietary iron. They include the following:

• Polyphenols (found in tea, coffee, red wine, berries, apples).
• Phytates (found in foods such as seeds, dried beans, soy, and bran). Such foods are typically high in fiber. (It is often believed that fiber itself impedes iron absorption, but researchers report that it has little or no effect.)
• Calcium. Calcium impairs the absorption of heme and non-heme iron. However, calcium intake must be quite high to cause any significant problems. For example, a 2002 study reported that cheese had no effect on iron absorption from meals rich in heme and non-heme iron.

Getting enough calcium to keep bones from thinning throughout a person's life may be made more difficult if that person has lactose intolerance or another reason, such as a tendency toward kidney stones, for avoiding calcium-rich food sources. Calcium deficiency also effects the heart and circulatory system, as well as the secretion of essential hormones. There are many ways to supplement calcium, including a growing number of fortified foods.

Sources of Vitamins B12 and Folate. Vitamins B12 and folate are important for prevention of megaloblastic anemia and good health in general.

• The only natural dietary sources of B12 are animal products, such as meats, dairy products, eggs, and fish (clams and oily fish are very high in B12); like other B vitamins, however, B12 is added to commercial dried cereals. The RDA is 2.4 mcg a day. Deficiencies are rare in young people, although the elderly may have trouble absorbing natural vitamin B12 and require synthetic forms from supplements and fortified foods.

Click the icon to see an image sources of vitamin B12.

• Folate is best found in avocado, bananas, orange juice, cold cereal, asparagus, fruits, green, leafy vegetables, dried beans and peas, and yeast. The synthetic form, folic acid, is now added to commercial grain products. Vitamins are usually made from folic acid, which is about twice as potent as folate. Many experts now recommend that adults have 400 mcg of folic acid daily, which is considerably higher than standard recommendations of 400 mcg of folate, which does not take into consideration the possible benefits of folate on the heart. Women who are trying to conceive, who are pregnant, and who are breastfeeding should take 400 mcg of folic acid.

Click the icon to see an image of sources of folate.

Preventing Anemia in Infants and Small Children

The main source of iron for an infant from birth to one year of age is in milk, either from breast milk, iron-fortified infant formula, or cereal. The best methods for preventing iron deficiency during infancy are the following:

Breastfeeding and Iron-Supplemented Formulas. Mothers should be encouraged to breastfeed their babies for their first year. Up to half of the iron in breast milk is absorbed by the baby and is sufficient to prevent anemia for the first four to six months, assuming that the mother had adequate iron stores during pregnancy. Breast milk itself is low in iron, but if the mother's diet is healthy, vitamin C and lactose in the breast milk may enhance iron absorption.

Breastfed babies should have iron supplements after four to six weeks, even if they are still nursing. Of note, a 2003 study reported better eyesight and higher test scores on psychologic and motor development in babies who received iron supplement during the time they were nursing. More research is needed to confirm such benefits.

In any case, infants who are not breastfed should start with iron-fortified formulas. Most experts strongly discourage the use of low-iron formulas (less than 4.0 mg/L). Of note, however, a 2002 study suggested that formulas with iron levels as low as 1.6 mg Fe/L provide sufficient iron to infants and higher amounts do not add any benefit. Parents should discuss the best formula with their doctor. Children given iron supplements may have a slightly higher risk for diarrhea. Experts advise against cow's milk for the first year of life.

Recommendations for Toddlers. Toddlers who did not have iron supplements during infancy should be checked for iron deficiency. After the first year, children should be given a varied diet that is rich in sources of iron, B vitamins, and vitamin C. Some experts recommend no more than 24 ounces of cow's milk a day (equal to three glasses). Some also advise iron-fortified vitamins or drinks, although this is controversial. It should be noted, that a preference for apple juice over vitamin-C rich orange juice does not reduce iron absorption in children with any otherwise healthy diet.