Robert D. Baker, MD, PhD, Frank R. Greer, MD and The Committee on Nutrition
PEDIATRICS Vol. 126 No. 5 November 2010, pp. 1040-1050 (doi:10.1542/peds.2010-2576)
Given that iron is the world's most common single-nutrient deficiency and there is some evidence of adverse effects of both iron deficiency (ID) and iron-deficiency anemia (IDA) on cognitive and behavioral development, it is important to minimize ID and IDA in infants and toddlers without waiting for unequivocal evidence. Controversies remain regarding the timing and methods used for screening for ID/IDA as well as regarding the use of iron supplements to prevent ID/IDA. Although further study is required to generate higher levels of evidence to settle these controversies, the currently available evidence supports the following recommendations.
Term, healthy infants have sufficient iron for at least the first 4 months of life. Human milk contains very little iron. Exclusively breastfed infants are at increasing risk of ID after 4 completed months of age. Therefore, at 4 months of age, breastfed infants should be supplemented with 1 mg/kg per day of oral iron beginning at 4 months of age until appropriate iron-containing complementary foods (including iron-fortified cereals) are introduced in the diet (see Table 3 in the original guideline document). For partially breastfed infants, the proportion of human milk versus formula is uncertain; therefore, beginning at 4 months of age, partially breastfed infants (more than half of their daily feedings as human milk) who are not receiving iron containing complementary foods should also receive 1 mg/kg per day of supplemental iron.
For formula-fed infants, the iron needs for the first 12 months of life can be met by a standard infant formula (iron content: 12 mg/dL) and the introduction of iron-containing complementary foods after 4 to 6 months of age, including iron-fortified cereals (see Table 3 in the original guideline document). Whole milk should not be used before 12 completed months of age.
The iron intake between 6 and 12 months of age should be 11 mg/day. When infants are given complementary foods, red meat and vegetables with higher iron content should be introduced early (see Table 3 in the original guideline document). To augment the iron supply, liquid iron supplements are appropriate if iron needs are not being met by the intake of formula and complementary foods.
Toddlers 1 through 3 years of age should have an iron intake of 7 mg/day. This would be best delivered by eating red meats, cereals fortified with iron, vegetables that contain iron, and fruits with vitamin C, which augments the absorption of iron (see Tables 3 and 4 in the original guideline document). For toddlers not receiving this iron intake, liquid supplements are suitable for children 12 through 36 months of age, and chewable multivitamins can be used for children 3 years and older.
All preterm infants should have an iron intake of at least 2 mg/kg per day through 12 months of age, which is the amount of iron supplied by iron-fortified formulas. Preterm infants fed human milk should receive an iron supplement of 2 mg/kg per day by 1 month of age, and this should be continued until the infant is weaned to iron-fortified formula or begins eating complementary foods that supply the 2 mg/kg of iron. An exception to this practice would include infants who have received an iron load from multiple transfusions of packed red blood cells.
Universal screening for anemia should be performed at approximately 12 months of age with determination of hemoglobin (Hb) concentration and an assessment of risk factors associated with ID/IDA. These risk factors would include low socioeconomic status (especially children of Mexican American descent [see Table 1 in the original guideline document]), a history of prematurity or low birth weight, exposure to lead, exclusive breastfeeding beyond 4 months of age without supplemental iron, and weaning to whole milk or complementary foods that do not include iron-fortified cereals or foods naturally rich in iron (see Table 3 in the original guideline document). Additional risk factors are the feeding problems, poor growth, and inadequate nutrition typically seen in infants with special health care needs. For infants and toddlers (1–3 years of age), additional screening can be performed at any time if there is a risk of ID/IDA, including inadequate dietary iron intake.
If the Hb level is less than 11.0 mg/dL at 12 months of age, then further evaluation for IDA is required to establish it as a cause of anemia. If there is a high risk of dietary ID as described in point 6 above, then further testing for ID should be performed, given the potential adverse effects on neurodevelopmental outcomes. Additional screening tests for ID or IDA should include measurement of:
Serum ferritin (SF) and C-reactive protein (CRP) levels
Reticulocyte hemoglobin content (CHr) concentration
If a child has mild anemia (Hb level of 10-11 mg/dL) and can be closely monitored, an alternative method of diagnosis would be to document a 1 g/dL increase in plasma Hb concentration after 1 month of appropriate iron-replacement therapy, especially if the history indicates that the diet is likely to be iron deficient.
Use of the serum transferrin receptor 1 (TfR1) assay as screening for ID is promising, and the American Academy of Pediatrics (AAP) supports the development of TfR1 standards for use of this assay in infants and children.
If IDA (or any anemia) or ID has been confirmed by history and laboratory evidence, a means of carefully tracking and following infants and toddlers with a diagnosis of ID/IDA should be implemented. Electronic health records could be used not only to generate reminder messages to screen for IDA and ID at 12 months of age but also to document that IDA and ID have been adequately treated once diagnosed.