Child Health, Agriculture and Integrated Nutrition (CHAIN): a randomized trial to close the nutrient gap in rural Zimbabwe

发育迟缓(儿童年龄的身高较低)影响着全球1.55亿5岁以下儿童，并导致更高的死亡风险、更差的学习成绩和更低的成年生活工资。改善两岁以下儿童食物的数量和质量是我们防止发育迟缓的最好方法。我们最近在津巴布韦农村地区做了一项名为SIRE的试验，结果表明，教育母亲有关婴幼儿喂养(IYCF)的知识，并给孩子每日补充(称为Nutributter)以提供额外的卡路里和维生素，有助于孩子长得更高。尽管如此，许多儿童仍然没有达到他们每天的营养需求，超过四分之一的儿童仍然发育迟缓。此外，发展中国家的儿童需要的营养素的数量可能高于发达国家，因为肠道发炎，吸收营养的能力较差。因此，我们需要增加孩子们获得的营养，并努力治愈肠道，帮助孩子们更好地成长。在这个项目中，我们将比较一套新的干预措施和SISH方法，看看我们是否可以缩小这种营养差距。近200个拥有6个月大婴儿的家庭将被随机分配(就像掷硬币一样)，获得SISH IYCF套餐(我们知道这种套餐可以减少发育迟缓)或新套餐，我们称之为IYCF-plus。接受SISH IYCF套餐的家庭将接受一名乡村卫生工作者的6次探访，以提供一系列关于如何为幼儿提供健康饮食的课程，包括每日营养食物。接受IYCF+一揽子计划的家庭将接受农业干预和更密集的喂养干预。家庭将获得三种新的作物品种(更耐干旱和虫害的强化玉米；富含蛋白质、维生素和钙的辣木树；以及含有易消化蛋白质、锌和铁的糖豆)，并将在种植和收获季节接受建议。我们希望这将增加家庭的食物供应，为儿童提供更多样化的食物选择，并改善饮食的营养含量。这些作物中含有的营养物质也可以帮助孩子的肠道愈合，这应该会促进食物的吸收。村卫生工作者将走访家庭12次，向Nutributter提供信息，并就如何喂养幼儿提供更深入的信息，包括使用新作物。家庭还将收到可以立即使用的粉状农作物版本(例如，通过添加到孩子的粥中)，然后家庭通过种植自己的作物实现自给自足。我们将比较18个月大的IYCF组和IYCF+组的儿童。主要结果将是每组中有多少儿童满足了他们每天的营养需求，方法是使用一份详细的问卷，该问卷回顾并称量孩子前一天吃的所有食物。我们认为，IYCF+组中将有更多的儿童满足他们的日常营养需求。我们还将测量他们的身高、体重、血细胞计数、体内肌肉和脂肪的数量，并收集血液、尿液和粪便样本。我们将使用这些样本来测量血液中的营养水平(如铁和蛋白质)，研究身体的新陈代谢(某些营养是如何分解和使用的)，并检验我们的理论，即IYCF+组的儿童肠道炎症较少。如果我们证明IYCF+干预导致更好的营养摄入，更健康的肠道，以及更高水平的血液营养，我们预计农业和婴儿联合喂养方法比Sare干预更能改善儿童的成长。这种方法具有可持续的优势，因为家庭可以种植和加工自己的作物供儿童食用，农村地区的卫生工作者可以提供必要的建议，以确保婴儿获得种植所需的食物。

Stunting (low height for a child's age) affects 155 million under-5 children around the world and leads to a higher risk of dying, poorer school performance and lower wages in adult life. Improving the quantity and quality of food for children under two years of age is the best approach we have to prevent stunting. We recently did a trial in rural Zimbabwe called SHINE, in which we showed that educating mothers about infant and young child feeding (IYCF) and giving the child a daily supplement (called Nutributter) to provide extra calories and vitamins, helped children grow taller. Despite this, many children still did not meet their daily nutrient requirements and over one-quarter remained stunted. In addition, the quantity of nutrients a child needs in developing countries is probably higher than in developed countries, because the gut is inflamed and less able to absorb nutrients. We therefore need to increase the nutrients children get and try to heal the gut, to help children grow better. In this project, we will compare a new package of interventions against the SHINE approach, to see if we can close this nutrient gap. Almost 200 households with a 6-month-old child will be randomly allocated (like the flip of a coin) to receive the SHINE IYCF package (which we know reduces stunting) or the new package, which we call "IYCF-plus". Households receiving the SHINE IYCF package will receive 6 visits from a Village Health Worker to provide a series of lessons in how to feed a young child a healthy diet, including daily Nutributter. Households receiving the IYCF-plus package will receive an agriculture intervention and a more intensive feeding intervention. Families will receive three new varieties of crops (fortified maize, which is more resistant to drought and pests; moringa trees, which contain high amounts of protein, vitamins and calcium; and sugar beans, which contain easily digestible protein, zinc and iron) and will receive advice during planting and harvesting seasons. We hope this will increase the family's food availability, provide a more diverse range of food choices for the child and improve the nutrient content of the diet. The nutrients contained in these crops may also help the child's gut to heal, which should improve absorption of the food. Village Health Workers will visit households 12 times to give Nutributter and to provide more intensive messages about how to feed a young child, including use of the new crops. Families will also receive powdered versions of the crops that can immediately be used (for example, by adding to the child's porridge) before the family becomes self-sufficient by growing their own.We will compare children in the IYCF and IYCF-plus groups at 18 months of age. The main outcome will be how many children in each group meet their daily nutrient requirements, using a detailed questionnaire that recalls and weighs all food the child ate in the previous day. We think that more children in the IYCF-plus group will meet their daily nutrient requirements. We will also measure their height, weight, blood count, the amount of muscle and fat in the body, and collect blood, urine and stool samples. We will use these samples to measure nutrient levels in the blood (such as iron and protein), to study the body's metabolism (how certain nutrients are broken down and used), and to test our theory that the children in the IYCF-plus group will have a less inflamed gut.If we show that the IYCF-plus intervention leads to better nutrient intake, a healthier gut, and higher levels of nutrients in the blood, we would expect the combined agriculture-infant feeding approach to improve children's growth more than the SHINE intervention did. This approach has the advantage of being sustainable because families can grow and process their own crops for the child to eat, and health workers in rural areas can provide the advice needed to ensure infants receive the food they need to grow.