Galetti Valeria, Kujinga Prosper, Mitchikpè Comlan Evariste S, Zeder Christophe, Tay Fabian, Tossou Félicien, Hounhouigan Joseph D, Zimmermann Michael B, Moretti Diego
Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland;
Division of Human Nutrition, Wageningen University, Wageningen, Netherlands;
Am J Clin Nutr. 2015 Nov;102(5):1238-48. doi: 10.3945/ajcn.115.117028. Epub 2015 Oct 14.
Zinc deficiency and contaminated water are major contributors to diarrhea in developing countries. Food fortification with zinc has not shown clear benefits, possibly because of low zinc absorption from inhibitory food matrices. We used a novel point-of-use water ultrafiltration device configured with glass zinc plates to produce zinc-fortified, potable water.
The objective was to determine zinc bioavailability from filtered water and the efficacy of zinc-fortified water in improving zinc status.
In a crossover balanced study, we measured fractional zinc absorption (FAZ) from the zinc-fortified water in 18 healthy Swiss adults using zinc stable isotopes and compared it with zinc-fortified maize porridge. We conducted a 20-wk double-blind randomized controlled trial (RCT) in 277 Beninese school children from rural settings who were randomly assigned to receive a daily portion of zinc-fortified filtered water delivering 2.8 mg Zn (Zn+filter), nonfortified filtered water (Filter), or nonfortified nonfiltered water (Pump) from the local improved supply, acting as the control group. The main outcome was plasma zinc concentration (PZn), and the 3 groups were compared by using mixed-effects models. Secondary outcomes were prevalence of zinc deficiency, diarrhea prevalence, and growth.
Geometric mean (-SD, +SD) FAZ was 7-fold higher from fortified water (65.9%; 42.2, 102.4) than from fortified maize (9.1%; 6.0, 13.7; P < 0.001). In the RCT, a significant time-by-treatment effect on PZn (P = 0.026) and on zinc deficiency (P = 0.032) was found; PZn in the Zn+filter group was significantly higher than in the Filter (P = 0.006) and Pump (P = 0.025) groups. We detected no effect on diarrhea or growth, but our study did not have the duration and power to detect such effects.
Consumption of filtered water fortified with a low dose of highly bioavailable zinc is an effective intervention in children from rural African settings. Large community-based trials are needed to assess the effectiveness of zinc-fortified filtered water on diarrhea and growth. These trials were registered at clinicaltrials.gov as NCT01636583 and NCT01790321.
锌缺乏和水污染是发展中国家腹泻的主要成因。用锌进行食品强化尚未显示出明显益处，这可能是因为在抑制性食物基质中锌的吸收率较低。我们使用一种配置有玻璃锌板的新型即用型水超滤装置来生产加锌的饮用水。
目的是确定过滤水中锌的生物利用度以及加锌水在改善锌状况方面的功效。
在一项交叉平衡研究中，我们使用锌稳定同位素测量了18名健康瑞士成年人从加锌水中的锌吸收分数（FAZ），并将其与加锌玉米粥进行比较。我们在277名来自农村的贝宁学龄儿童中进行了一项为期20周的双盲随机对照试验（RCT），这些儿童被随机分配每天饮用一份提供2.8毫克锌的加锌过滤水（锌 + 过滤器组）、未加锌的过滤水（过滤器组）或来自当地改良供水的未加锌未过滤水（水泵组），水泵组作为对照组。主要结局是血浆锌浓度（PZn），并使用混合效应模型对三组进行比较。次要结局是锌缺乏患病率、腹泻患病率和生长情况。
加锌水的几何平均（-标准差，+标准差）FAZ（65.9%；42.2，102.4）比加锌玉米粥高7倍（9.1%；6.0，13.7；P < 0.001）。在随机对照试验中，发现治疗时间对PZn（P = 0.026）和锌缺乏（P = 0.032）有显著影响；锌 + 过滤器组的PZn显著高于过滤器组（P = 0.006）和水泵组（P = 0.025）。我们未检测到对腹泻或生长的影响，但我们的研究没有足够的时长和效力来检测此类影响。
饮用添加低剂量高生物利用度锌的过滤水对非洲农村儿童是一种有效的干预措施。需要进行大规模的社区试验来评估加锌过滤水对腹泻和生长的有效性。这些试验已在clinicaltrials.gov上注册，注册号为NCT01636583和NCT01790321。
