DIETARY PATTERNS, MINERAL AND VITAMIN METABOLISM
Location: Obesity and Metabolism Research Unit
Title: INTERNATIONAL RESEARCH ON INFANT SUPPLEMENTATION STUDY: RANDOMIZED CONTROLLED TRIALS OF MICRONUTRIENT SUPPLEMENTATION DURING INFANCY
Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 1, 2005
Publication Date: November 1, 2005
Citation: Allen, L.H., Shrimpton, R. 2005. INTERNATIONAL RESEARCH ON INFANT SUPPLEMENTATION STUDY: IMPLICATIONS FOR PROGRAMS AND FURTHER RESEARCH. Journal of Nutrition. 135:666S-669S.
Interpretive Summary: The purpose of this is to provide perspective on the results, compared the effect of different micronutrient supplements on infant development in four countries, together with program and research implications. The overall biological coherence and consistency of the IRIS study results confer great plausibility to the findings. There was a significant dose-response effect between the weekly multiple micronutrient and the daily multiple micronutrient supplements for hemoglobin, plasma ferritin, zinc, retinol, homocysteine, tocopherol, and erythrocyte riboflavin concentrations. For all of these outcomes, when compared with placebo, the effect produced by weekly multiple micronutrient supplements, which contained twice the recommended daily intake taken on one day of the week (2/7), was half that produced by the daily multiple micronutrient, which contained one daily intake taken each day of the week (7/7). Similar effects were seen in weight gain where, compared with those receiving iron or placebo supplements, infants receiving the multiple micronutrient supplements for 6 mo were heavier by 180 g when taking them daily and by 90 g when taking them weekly.
The International Research on Infant Supplementation (IRIS) studies, performed in 4 developing country settings across the world and presented in this supplement, show that the use of a daily multiple micronutrient supplement during infancy is more efficacious for improving micronutrient status, anemia, and child weight growth than a daily iron supplement or a multiple micronutrient supplement. Neither iron nor multiple micronutrient supplementation prevented growth faltering and, although in the pooled analysis the daily multiple micronutrient supplementation produced a small breaking effect on weight-growth faltering compared with placebo, length-growth faltering was the same in all groups. Infants receiving the daily multiple micronutrient supplement showed improved concentrations of circulating hemoglobin and of plasma ferritin, zinc, retinol, riboflavin, homocysteine, and tocopherol, whereas daily iron supplements and weekly multiple micronutrient supplements only improved hemoglobin and plasma ferritin concentrations. The morbidity data were not collected in comparable ways across countries, but in those country studies that reported morbidity, there was no difference between any supplementation group and placebo.