Significant heterogeneity was evident , and its predictors included greater weight-for-age in supplemented children in malaria hyperendemic regions and greater weight-for-height for children above 5 years of age , but a negative effect on linear growth in developed countries and with supplementation for 6 months or longer .
This review did not document a positive effect of iron supplementation on the physical growth of children .
OBJECTIVE To evaluate the effect of iron supplementation on  physical growth in children through a systematic review of r and omised controlled trials ( RCTs ) .
Adverse effect of iron supplementation on weight gain of iron-replete young children
The efficacy of iron supplementation for iron-deficient subjects is in no doubt . However , the assumption that iron supplementation of iron-replete subjects is harmless may not be valid . We have studied the effect of iron supplementation on growth rate in 47 iron-sufficient young children ( 12 - 18 months ) in Indonesia . The children were r and omly assigned either ferrous sulphate ( 3 mg/kg daily ) or placebo every day for 4 months . Before treatment the length , weight , and arm circumference of the two groups were similar . During the 4 months of supplementation the rate of weight gain was significantly greater in the placebo group than in the iron-supplemented group ( 0.106 [ SE 0.010 ] vs 0.070 [ 0.011 ] kg every 2 weeks , p = 0.02 ) . The rates of gain in length and arm circumference did not differ significantly by treatment . There were no differences between the groups in rates of respiratory and gastrointestinal infections . These results suggest that iron supplementation of iron-replete children may retard their growth
Significant heterogeneity was evident , and its predictors included greater weight-for-age in supplemented children in malaria hyperendemic regions and greater weight-for-height for children above 5 years of age , but a negative effect on linear growth in developed countries and with supplementation for 6 months or longer .
This review did not document a positive effect of iron supplementation on the physical growth of children .
OBJECTIVE To evaluate the effect of iron supplementation on  physical growth in children through a systematic review of r and omised controlled trials ( RCTs ) .