Table 4.

Zinc in prevention and treatment of infections

Subjects	N	Intervention		Findings	Reference
Human
Young Guatemalan children, 6–9 mo	44 (P) 45 (Z)	10 mg zinc/d as zinc sulfate for 7 mo (on average)	Diarrhea, RI	-22% reduction in prevalence of diarrhea -no effect on incidence of RI	Ruel et al. 1997 [136]
Institutionalized elderly, >65 y	(P) (Z+S)	20 mg zinc/d as sulfide plus 100 μg selenium/d as sulfide for 2 y	Infection	-Decrease the mean number of RI	Girodon et al. 1997 [138]
Institutionalized elderly, >65 y	182 (P) 182 (Z+S)	20 mg zinc/d as sulfide plus 100 μg selenium/d as sulfide for 2 y	Infection	-Increase humoral response -A tendency for higher number of subjects without RI (p=0.06) -No effect on DTH response	Girodon et al. 1999 [139]
Severe pneumonia patients, 2–23 mo	149 (P) 150 (Z)	20 mg zinc sulfate/d during hospitalization	Pneumonia	-Increase duration of pneumonia in the hot season	Bose et al. 2006 [261]
Institutionalized elderly, 55–87 y	25 (P) 24 (Z) 6 (P) 6 (Z)	45 mg zinc/d as zinc gluconate for 1 y 45 mg zinc/d as zinc gluconate for 6 mo	Infection	-Less infection and fever, a tendency for fewer common cold and upper RI -Reduce ex vivo TNF-α production in response to LPS -Increase IL-2 mRNA in a separate 6 mo-zinc supplementation study	Prasad et al. 2007 [140]
Institutionalized elderly, >65 y	420 (Z)	7 mg zinc/d as zinc sulfate with vitamin and mineral	Infection	-Lower pneumonia incidence, reduced total antibiotic use, and shorter duration of pneumonia and antibiotic use in subjects with adequate blood zinc (>70 mg/dL) post-intervention	Meydani et al. 2007 [141]
Sickle-cell disease patients	18 (P) 18 (Z)	75 mg zinc/d as zinc acetate for 3 mo	Infection	-Lower incidence of total number of infection, upper RI, a trend in common cold (p=0.074) -Increase IL-2 and IFN-γ and decrease TNF-α and IL-1β ex vivo production -Increase IL-2 and IL-2Rα mRNA and decrease TNF-α and IL-1β mRNA levels	Bao et al. 2008 [137]
Severe pneumonia patients, 2–23 mo	146 (P) 149 (Z)	20 mg zinc sulfate/d during hospitalization	Pneumonia	-A longer hospital stay and a slower recovery in suspected bacterial pneumonia (CRP>40 mg/dL) -No difference in suspected non-bacterial pneumonia	Coles et al. 2007 [262]
Pulmonary tuberculosis (PTB) patients, >15 y	116 (P) 117 (Z)	90 mg zinc/wk as sulfate for 9 wk	PTB	-No effect on sputum conversion rate, resolution of radiographic abnormalities, cough, and fever	Lawson et al. 2010 [263]
Malnourished PTB patients, 15–55 y	86 (P) 76 (Z)	15 mg zinc/d as sulfate for 6 mo	PTB	-No effect on plasma zinc and sputum conversion rate	Pakasi et al 2010 [264]

(P) placebo, (Z) zinc supplementation, (Z+S) zinc plus selenium supplementation, PTB: pulmonary tuberculosis