Zinc and Multi-vitamin Supplementation Have Contrasting Effects on Infant Iron Status: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Abstract

BACKGROUND—Zinc supplementation adversely affects iron status in animal and adult human studies but few, trials have included young infants. OBJECTIVE—To determine the effects of zinc and multivitamin supplementation on infant hematologic and iron status. METHODS—In a double-blind RCT, Tanzanian infants were randomized to daily, oral zinc (Zn), multivitamins (MV), Zn and MV, or placebo treatment arms at age 6 wk. Hemoglobin CONCLUSIONS—MV treatment improved iron status in infancy, whereas Zn worsened iron status but without an associated increase in risk for anemia. Infants in long-term zinc supplementation programs at risk for ID may benefit from screening and/or the addition of a multivitamin supplement. Keywords Iron supplementation; Zinc supplementation; Iron deficiency; Iron deficiency anemia; anemia; microcytic anemia