School of Food Science and Nutrition, University of Leeds, Leeds, UK.
Crit Rev Food Sci Nutr. 2022;62(6):1568-1591. doi: 10.1080/10408398.2020.1844636. Epub 2020 Nov 12.
This paper reviews and analyses the importance of maize as staple food in Eastern and Southern Africa (E&SA) and contributes in understanding the nexus between maize nutritional composition and prevalence of micronutrient deficiencies (MNDs) in these regions. MNDs remain a major public health concern particularly for women and children, with calcium, iodine, iron, selenium, zinc, folate and vitamin A deficiencies being the most common. Estimates of their prevalence are among the highest in E&SA: iron-deficient anemia affected 26 to 31% of women of reproductive age, and deficiencies up to 53%, 36%, 66%, 75% and 62% for vitamin A, iodine, zinc, calcium and selenium, respectively, were measured in populations of these regions. Besides, these two regions show the highest worldwide maize per capita consumption (g/person/day) as main staple, with 157 in Eastern Africa and 267 in Southern Africa, including up to 444 in Lesotho. The analysis of food composition tables from these regions showed that 100 g of maize foods consumed by these populations could to some extent, contribute in satisfying dietary reference intakes (DRIs) of children and women in energy, proteins, carbohydrates, magnesium, zinc, vitamins B1 and B6. However, it provides very low supply of fats, calcium, sodium, selenium, vitamins C, A and E. The high occurrence of MNDs and considerable nutritional potential of maize consumed in E&SA can be explained by loss of nutrients due to processing practices, low food diversification and reduced nutrients bioavailability. Success cases of the main strategies to tackle the issue of MNDs in these regions by improving maize nutritional quality are discussed in this paper. Maize fortification was shown to improve nutrition and health outcomes of population. Increasing dietary diversity by complementing maize with other foods has improved nutrition through integration of micronutrient-rich foods in the diet. Mostly, biofortification has successfully contributed in reducing vitamin A and zinc deficiencies in rural communities more than nutrient supplementation, fortification and dietary diversity.
本文回顾和分析了玉米作为主食在东部和南部非洲(E&SA)的重要性,并有助于理解玉米营养成分与这些地区微量营养素缺乏症(MNDs)流行之间的关系。MNDs 仍然是一个主要的公共卫生关注点,特别是对妇女和儿童而言,其中最常见的缺乏症是钙、碘、铁、硒、锌、叶酸和维生素 A。这些地区的 MNDs 流行率估计是全球最高的:育龄妇女缺铁性贫血的发病率为 26%至 31%,分别有 53%、36%、66%、75%和 62%的人群缺乏维生素 A、碘、锌、钙和硒。此外,这两个地区的人均玉米消费量(克/人/天)最高,东非为 157 克,南非为 267 克,其中莱索托高达 444 克。对这些地区的食物成分表进行分析表明,这些人群食用 100 克玉米食品,在一定程度上可以满足儿童和妇女的能量、蛋白质、碳水化合物、镁、锌、维生素 B1 和 B6 的膳食参考摄入量(DRIs)。然而,玉米提供的脂肪、钙、钠、硒、维生素 C、A 和 E 含量非常低。E&SA 地区 MNDs 高发和玉米消费可观的营养潜力可以用加工实践造成的营养素损失、食物种类单一和降低的营养素生物利用度来解释。本文讨论了这些地区改善玉米营养质量的主要策略在解决 MNDs 问题方面的成功案例。玉米强化已被证明可以改善人口的营养和健康状况。通过将其他食物与玉米搭配来增加饮食的多样性,通过将富含微量营养素的食物纳入饮食,改善了营养状况。生物强化在减少农村社区的维生素 A 和锌缺乏方面比营养补充、强化和饮食多样性更成功。