The Effects of Salt Fortified with Multiple Nutrients on Health Outcomes in Children, Adolescents, and Adults: A Systematic Review and Meta-Analysis

IF 12.7 1区医学 Q1 NUTRITION & DIETETICS

Advances in Nutrition Pub Date : 2026-01-01 Epub Date: 2025-12-04 DOI:10.1016/j.advnut.2025.100567

Gitanjali Lall , Michael B Zimmermann , Werner Schultink , Leila M Larson

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引用次数: 0

Abstract

Nutritional deficiencies are prevalent in populations across the world. Fortification of staple foods has been used as an alternative to supplementation to address many deficiencies. One such staple is salt, which has long been fortified with iodine, but more recently with iron, folate, and other micronutrients. Our objective was to determine the effects of fortified salt on nutritional and health outcomes among children, adolescents, and adults. We conducted a systematic review of published and unpublished literature using a pre-defined search strategy. Abstracts and full texts were screened for randomized trials, quasi-randomized trials, and pre-post-designs of double or multiple fortified salt. We calculated the weighted pooled effect sizes for the effects of fortified salt on nutritional and health outcomes. Of the 395 studies identified, 33 (including 37 intervention-control comparisons) fit our inclusion criteria. Of these comparisons, 26 studied the effects of salt fortified with iron and iodine [double fortified salt (DFS)], 2 studied the effects of salt fortified with folic acid and iodine, 1 studied the effect of triple fortified salt, 1 studied the effect of quadruple fortified salt, and 7 studied the effects of multiple micronutrient fortified salt (MMFS; fortified with ≥5 nutrients). Pooled effect sizes indicated positive effects from all iron-containing fortified salt on hemoglobin concentration [standardized mean difference (95% confidence interval): DFS 0.36 (0.22, 0.50), n comparisons = 26; triple fortified salt 1.56 (1.42, 1.70), n comparisons = 1; quadruple fortified salt 0.33 (0.02, 0.63), n comparisons = 1; MMFS 0.23 (0.03, 0.43), n comparisons = 6]. DFS and MMFS reduced the odds of anemia and iron deficiency (ID) anemia. MMFS improved serum folate and reduced the odds of ID. Pooled effects on biomarkers of vitamin B12, vitamin A, and zinc status varied by type of salt, but were largely not significant. Fortification of salt with iodine and iron, with and without other nutrients, is effective in increasing hemoglobin and reducing the odds of anemia and ID in population-based studies.

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多种营养素强化盐对儿童、青少年和成人健康结果的影响：一项系统综述和荟萃分析

营养缺乏在世界各地的人群中普遍存在。主食的强化已被用作补充剂的替代品，以解决许多缺陷。其中一种主食就是盐，长期以来，盐中一直添加了碘，但最近又添加了铁、叶酸和其他微量营养素。我们的目的是确定强化盐对儿童、青少年和成人的营养和健康结果的影响。我们使用预定义的搜索策略对已发表和未发表的文献进行了系统的综述。摘要和全文被筛选为随机试验、准随机试验和双重或多重强化盐的前后设计。我们计算了强化盐对营养和健康结果影响的加权合并效应大小。在确定的395项研究中，33项（包括37项干预对照比较）符合我们的纳入标准。在这些比较中，26项研究了铁和碘强化盐（DFS）的效果，2项研究了叶酸和碘强化盐（FISFA）的效果，1项研究了三重强化盐（TFS）的效果，1项研究了四倍强化盐（QFS）的效果，7项研究了多种微量营养素强化盐（MMFS；至少强化了5种营养素）的效果。合并效应量表明，所有含铁强化盐对血红蛋白浓度有积极影响[标准化平均差（95% CI）： DFS 0.36 (0.22, 0.50), n=26个比较；TFS 1.56 (1.42, 1.70), n=1；QFS 0.33 (0.02, 0.63), n=1；MMFS 0.23 (0.03, 0.43), n =6]。DFS和MMFS降低了贫血和缺铁性贫血的几率。MMFS改善了血清叶酸，降低了缺铁的几率。对维生素B12、维生素A和锌的生物标志物的综合影响因盐的种类而异，但基本上不显著。在以人群为基础的研究中，用碘和铁强化盐，无论是否有其他营养素，都能有效地增加血红蛋白，减少贫血和缺铁的几率。

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来源期刊

Advances in Nutrition 医学-营养学

CiteScore

17.40

自引率

2.20%

发文量

117

审稿时长

56 days

期刊介绍： Advances in Nutrition (AN/Adv Nutr) publishes focused reviews on pivotal findings and recent research across all domains relevant to nutritional scientists and biomedical researchers. This encompasses nutrition-related research spanning biochemical, molecular, and genetic studies using experimental animal models, domestic animals, and human subjects. The journal also emphasizes clinical nutrition, epidemiology and public health, and nutrition education. Review articles concentrate on recent progress rather than broad historical developments. In addition to review articles, AN includes Perspectives, Letters to the Editor, and supplements. Supplement proposals require pre-approval by the editor before submission. The journal features reports and position papers from the American Society for Nutrition, summaries of major government and foundation reports, and Nutrient Information briefs providing crucial details about dietary requirements, food sources, deficiencies, and other essential nutrient information. All submissions with scientific content undergo peer review by the Editors or their designees prior to acceptance for publication.