Low-Dose Iron Supplementation in Infancy Modestly Increases Infant Iron Status at 9 Mo without Decreasing Growth or Increasing Illness in a Randomized Clinical Trial in Rural China
BACKGROUND: Previous trials of iron supplementation in infancy did not consider maternal iron supplementation. OBJECTIVE: This study assessed effects of iron supplementation in infancy and/or pregnancy on infant iron status illnesses and growth at 9 mo. METHODS: Enrollment occurred from December 2009 to June 2012 in Hebei China. Infants born to women in a pregnancy iron supplementation trial were randomly assigned 1:1 to iron [ approximately 1 mg Fe/(kg . d) as oral iron proteinsuccynilate] or placebo from 6 wk to 9 mo excluding infants with cord ferritin /=2 abnormal iron measures) or body iron 60% of infants still had ID at 9 mo. Receiving more bottles of iron in infancy was associated with better infant iron status at 9 mo but only among iron-supplemented infants whose mothers were also iron supplemented (i.e. the iron/iron group). There were no group differences in hospitalizations or illnesses and no adverse effects on growth overall or among infants who were iron sufficient at birth. CONCLUSIONS: Iron supplementation in Chinese infants reduced ID at 9 mo without adverse effects on growth or illness. Effects of iron supplementation in pregnancy were observed only when higher amounts of iron were distributed in infancy. This trial was registered at clinicaltrials.gov as NCT00613717. (c) 2016 American Society for Nutrition.