Limited evidence suggested that iron supplementation produced a small improvement in cognitive development but had no effect on physical growth .
CONCLUSIONS : In 2 to 5 year olds , daily iron supplementation increases hemoglobin and ferritin .
There is a concerning lack of data on the effect of iron supplementation on clinical ly important outcomes including anemia , ID anemia , ID , and cognitive development .
BACKGROUND AND OBJECTIVES : Iron deficiency ( ID ) is the most common cause of anemia worldwide .
The prevalence is highest among preschool-aged children .
Iron is widely administered to children with or at risk for ID , but evidence of benefit among 2- to 5-year-old children has not been evaluated by systematic review .
We summarize the evidence for the benefit and safety of daily iron supplementation with regard to hematologic , growth , and cognitive parameters in 2 to 5 year olds .
Efficacy of Daily and Weekly Iron Supplementation on Iron Status in Exclusively Breast-Fed Infants
Iron deficiency anemia ( IDA ) remains the most prevalent nutritional deficiency in infants worldwide . The purpose of this study was to determine the efficacy of daily and weekly iron supplementation for 3 months to improve the iron status in 4-month-old , exclusively breast-fed healthy infants . Infants 4 months of age were eligible for the open , r and omized controlled trial if their mothers intended to continue exclusive breast-feeding until the infants were 6 months of age . Infants or mothers with iron deficiency ( ID ) or IDA on admission were excluded . The infants ( n = 79 ) were r and omly assigned to three groups , the first group receiving daily ( 1 mg/kg daily ) , the second group weekly ( 7 mg/kg weekly ) , and the third group no iron supplementation .  Anthropometric measurements were taken on admission and at 6 and 7 months of age . Iron status was analyzed on admission and monthly for 3 months . Both hematologic parameters and anthropometric measurements were found to be similar among the three groups during the study period . Seven infants ( 31.8 % ) in the control group , six ( 26.0 % ) in the daily group , and three ( 13.6 % ) in the weekly group developed ID or IDA ( P > 0.05 ) . Infants whose mothers had ID or IDA during the study period were more likely to develop ID or IDA independently from iron supplementation . Serum ferritin levels decreased between 4 and 6 months of age in the control and daily groups ; the weekly group showed no such decrease . In all groups , the mean levels of serum ferritin were significantly increased from 6 months to 7 months of age during the weaning period . In this study , which had a limited number of cases , weekly or daily iron supplementation was not found to decrease the likelihood of IDA . In conclusion , exclusively breast-fed infants with maternal IDA appeared to be at increased risk of developing IDA
Limited evidence suggested that iron supplementation produced a small improvement in cognitive development but had no effect on physical growth .
CONCLUSIONS : In 2 to 5 year olds , daily iron supplementation increases hemoglobin and ferritin .
There is a concerning lack of data on the effect of iron supplementation on clinical ly important outcomes including anemia , ID anemia , ID , and cognitive development .
BACKGROUND AND OBJECTIVES : Iron deficiency ( ID ) is the most common cause of anemia worldwide .
The prevalence is highest among preschool-aged children .
Iron is widely administered to children with or at risk for ID , but evidence of benefit among 2- to 5-year-old children has not been evaluated by systematic review .
We summarize the evidence for the benefit and safety of daily iron supplementation with regard to hematologic , growth , and cognitive parameters in 2 to 5 year olds .