A Micronutrient Powder with Low Doses of Highly Absorbable Iron and Zinc Reduces Iron and Zinc Deficiency and Improves Weight-For-Age Z-Scores in South African Children

Abstract

Micronutrient powders (MNP) are often added to complementary foods high in inhibitors of iron and zinc absorption. Most MNP therefore include high amounts of iron and zinc, but it is no longer recommended in malarial areas to use untargeted MNP that contain the Reference Nutrient Intake for iron in a single serving. The aim was to test the efficacy of a low-iron and -zinc (each 2.5 mg) MNP containing iron as NaFeEDTA, ascorbic acid (AA), and an exogenous phytase active at gut pH. In a double-blind controlled trial, South African school children with low iron status (n = 200) were randomized to receive either the MNP or the unfortified carrier added just before consumption to a high-phytate maize porridge 5 d/wk for 23 wk; primary outcomes were iron and zinc status and a secondary outcome was somatic growth. Compared with the control, the MNP increased serum ferritin (P < 0.05), body iron stores (P < 0.01) and weight-for-age Z-scores (P < 0.05) and decreased transferrin receptor (P < 0.05). The prevalence of iron deficiency fell by 30.6% (P < 0.01) and the prevalence of zinc deficiency decreased by 11.8% (P < 0.05). Absorption of iron from the MNP was estimated to be 7-8%. Inclusion of an exogenous phytase combined with NaFeEDTA and AA may allow a substantial reduction in the iron dose from existing MNP while still delivering adequate iron and zinc. In addition, the MNP is likely to enhance absorption of the high native iron content of complementary foods based on cereals and/or legumes.

The effects of iron fortification and supplementation on the gut microbiome and diarrhea in infants and children: a review

“…In the MixMe MNP, NaFeEDTA is combined with ascorbic acid and an exogenous phytase, both of which are enhancers of iron absorption, and this combination results in higher iron absorption from maize porridge (16). This MNP has shown to have weak efficacy in preschool children in Kenya (19) and school-age children in South Africa (20); however, in a 1-y controlled trial in Kenyan infants, the MNP did not reduce IDA (21), possibly because the absorbed iron dose was insufficient as a result of the low dose and the high prevalence of infections increasing serum hepcidin (12). Thus, it is uncertain how far the iron dose in MNPs can be lowered while maintaining efficacy against anemia.…”

Current Progresses in Phytase Research: Three‐Dimensional Structure and Protein Engineering

“…The side chains of A35E and P42S residues in AnPhyA, located in the N-terminal region, are presented as stick models, and the putative H-bonds between two residues are shown as dash lines. ble 3 10 helix, which is considered prone to collapse at high temperatures. Indeed, deleting the C-terminal region resulted in 39 % higher residual activity at 80°C [48].…”

“…The global market of phytase in animal feed is estimated to exceed 300 million US-$ and continues to grow with a rate of 10 % per year [9]. In addition to the feed industry, phytases have been utilized in creating transgenic plant and animal feed, improving human nutrition [10][11][12], and biosynthesis of various lower myo-inositol phosphates [13,14]. With such great economic potentials and extensive biotechnological applications, phytase is one of the most important research targets of both academic and commercial interests.…”

Zinc and Dietary Fibre: Competing Nutrients in the Management of Chronic Diseases

“…In addition, an increase in the availability of zincfortified foods is likely to have had a positive impact on the zinc status of some groups, highlighting the need for updated information on zinc bioavailability from a range of diets, particularly in LMIC. Plant breeding practices that decrease the PA content of plant foods [11] and/or the inclusion of phytases in processed foods [12] are options that currently are being explored in the search to maximize zinc bioavailability. …”