Study Author Country Study Population Dosage Results Effect of zinc supplementation between 1 and 6 months of life on growth and morbidity of Bangladeshi infants in urban slums. Osendarp et al., 2002 [269] Bangladesh 300 infants from Dhaka slum area, from 4 weeks to 24 weeks of age 5 mg/day for 20 weeks Reduced incidence of ALRI and greater weight gains. Effect of zinc supplementation started during diarrhea on morbidity and mortality in Bangladeshi children: community randomised trial. Baqui et al., 2002 [270] Bangladesh 8070 children 20 mg/day for 14 days in case of diarrhea episodes Reduced incidence of diarrhea and ALRI. Simultaneous weekly supplementation of iron and zinc is associated with lower morbidity due to diarrhea and acute lower respiratory infection in Bangladeshi infants. Baqui et al., 2003 [271] Bangladesh 799 infants Different micronutrient formulations, some including zinc 20 mg weekly for 6 months Lower risk of severe ALRI in the group receiving iron + zinc. Effect of weekly zinc supplements on incidence of pneumonia and diarrhea in children younger than 2 years in an urban, low-income population in Bangladesh: randomised controlled trial. Brooks et al., 2005 [272] Bangladesh 1621 children aged 60 days to 12 months 70 mg weekly for 12 months Reduced pneumonia incidence and mortality. The prophylactic and therapeutic effectiveness of zinc sulphate on common cold in children. Kurugol et al., 2006 [273] Turkey 200 children 15 mg/day for 7 months, increased to 30 mg/day during colds Significantly lower mean number of colds and duration of symptoms. Zinc and iron supplementation and malaria, diarrhea, and respiratory infections in children in the Peruvian Amazon. Richard et al., 2006 [274] Perù 855 children Iron, zinc (20 mg/day), or iron + zinc for 7 months No statistically significant effect on incidence of respiratory infections. A double-blind, randomized, clinical trial of the effect of vitamin A and zinc supplementation on diarrhea and respiratory tract infections in children in Mexico City, Mexico. Long et al., 2006 [275] Mexico 736 children living in a peri-urban area Vitamin A vs. 20 mg zinc daily vs. vitamin A + zinc vs. placebo for 12 months No effect on the incidence of respiratory infections. Zinc or multiple micronutrient supplementation to reduce diarrhea and respiratory disease in South African children: a randomized controlled trial. Luabeya et al., 2007 [276] South Africa Over 370 children from a rural community Vitamin A vs. zinc 10 mg/day + vitamin A vs. a multi micronutrients supplement, from 6 to 24 months of age No reduction in diarrhea and respiratory morbidity. Effect of zinc supplementation on mortality in children aged 1–48 months: a community-based randomised placebo-controlled trial. Sazawal et al., 2007 [277] Zanzibar 42,546 children 10 mg/day (5 mg in children younger than 12 months) until 48 months of age Non-significant reduction in the relative risk of all-cause mortality. Adding zinc to supplemental iron and folic acid does not affect mortality and severe morbidity in young children. Bhandari et al., 2007 [278] India 94,359 children 10 mg daily for 12 months No significant difference in death and hospitalization rates. Effect of daily zinc supplementation on child mortality in southern nepal: a community-based, cluster randomised, placebo-controlled trial. Tielsch et al., 2007 [279] Nepal Over 40,000 children zinc 10 mg/day vs. other supplements vs. placebo for 12 months Not significantly different mortality rate sand frequency of respiratory infections. Zinc supplementation for prevention of acute respiratory infections in infants: a randomized controlled trial. Malik et al., 2014 [280] India 272 children with acute respiratory infections 20 mg/day for 2 weeks Decrease in duration of the episode, lower frequency of future ALRIs. Occurrence of infections in schoolchildren subsequent to supplementation with vitamin D-calcium or zinc: a randomized, double-blind, placebo-controlled trial. Mandlink et al., 2020 [281] India 435 schoolchildren (Children in the zinc arm)10 mg/day for 7 months No significant reduction in the occurrence of infections.