Effectiveness of zinc-fortified water on zinc intake, status and morbidity in Kenyan pre-school children: a randomised controlled trial.

Objective: Zn deficiency and diarrhoea are prevalent and may coexist in children living in low-resource settings. Recently, a novel approach for delivering Zn via microbiologically treated, Zn-fortified water was shown to be effective in improving Zn status in West African schoolchildren. We assessed the effectiveness of Zn-fortified, microbiologically purified water delivered as a household intervention on Zn intake, status and morbidity in children aged 2-6 years from rural western Kenya. Design: Randomised controlled trial. Intervention included households assigned to water treatment device with (ZFW) or without (FW) Zn delivery capability Setting: Rural households in Kisumu, western Kenya. Subjects: Children aged 2-6 years. Results: The ZFW group had higher dietary Zn intake compared with the FW group. ZFW contributed 36 and 31% of daily requirements for absorbable Zn in children aged 2-3 and 4-6 years, respectively, in the ZFW group. Consumption of Zn-fortified water resulted in lower prevalence of reported illness (risk ratio; 95% CI) in the ZFW group compared with the FW group: for cold with runny nose (0.91; 0.83, 0.99; P= 0.034) and abdominal pain (0.70; 0.56, 0.89; P= 0.003) in the intention-to-treat analysis and for diarrhoea (0.72; 0.53, 0.96; P=0.025) in the per-protocol analysis. We did not detect an effect of treatment on plasma Zn concentration. Conclusions: Daily consumption of Zn-fortified, microbiologically treated water results in increased intake of absorbable dietary Zn and may help in preventing childhood infections in pre-school children in rural Africa.