Center for Food Science and Nutrition, Addis Ababa University, Addis Ababa, Ethiopia.
Proc Nutr Soc. 2019 Nov;78(4):540-546. doi: 10.1017/S0029665119000557. Epub 2019 Mar 11.
Micronutrient deficiencies are widespread and disproportionately affect women and children in low- and middle-income countries (LMIC). Among various interventions, food fortification and supplementation with micronutrients have been proven to be cost-effective. The aim of the present paper is to review existing literature to assess risks of excessive intake in LMIC to then highlight programmatic changes required to maximise benefits of micronutrient interventions while minimising risks of adverse effects. While very few LMIC have national food consumption surveys that can inform fortification programmes, many more are implementing mandatory fortification programmes. The risks of inadequate micronutrient intakes were common, but risks of excessive intakes were also present for iodine, vitamin A, folic acid and iron. Excessive salt consumption, high concentrations of iodine in ground-water and excessive levels of iodisation were linked with excessive iodine intake. For vitamin A, overlapping interventions were the main risk for excessive intake; whereas for iron, contamination with iron from soil and screw-wares of millers and high iron concentration in drinking-water increased the risk of excessive intake, which could be further exacerbated with fortification. Before implementing micronutrient interventions, adherence to the basic principles of documenting evidence confirming that the deficiency in question exists and that fortification will correct this deficiency is needed. This can be supported with dietary intake assessments and biochemical screening that help diagnose nutrient deficiencies. Targeting micronutrient interventions, although programmatically challenging, should be considered whenever possible. Moreover, closer monitoring of appropriate fortification of foods and overlapping interventions is needed.
微量营养素缺乏广泛存在，且不成比例地影响中低收入国家（LMIC）的妇女和儿童。在各种干预措施中，食物强化和补充微量营养素已被证明是具有成本效益的。本文的目的是回顾现有文献，评估 LMIC 中过度摄入的风险，然后强调需要进行方案性改变，以最大限度地提高微量营养素干预措施的效益，同时将不良反应的风险降至最低。虽然只有极少数 LMIC 有可以为强化计划提供信息的国家食物消费调查，但更多的国家正在实施强制性强化计划。微量营养素摄入不足的风险很常见，但碘、维生素 A、叶酸和铁的摄入过量风险也存在。盐摄入不足、地下水碘含量高以及碘强化水平过高与碘摄入过量有关。对于维生素 A，重叠干预是摄入过量的主要风险；而对于铁，土壤和磨粉机螺丝中的铁污染以及饮用水中铁浓度升高增加了摄入过量的风险，强化可能会进一步加剧这种风险。在实施微量营养素干预措施之前，需要遵循记录证据的基本原则，确认存在所讨论的营养素缺乏，并且强化将纠正这种缺乏。这可以通过饮食摄入评估和生化筛查来支持，这些方法有助于诊断营养缺乏症。尽管在方案上具有挑战性，但应尽可能考虑针对微量营养素干预措施。此外，还需要更密切地监测适当的食物强化和重叠干预。
