Effects of zinc alone versus multiple micronutrients on IGFBP3, IGF1 and growth in Laotian children
• Although supplementation with zinc alone improves growth, multiple micronutrient supplementation is a more desirable strategy for targeting multiple micronutrient deficiency in low income settings. Because supplementation with a standard MNP (containing 4.1-5 mg Zn, 12. 5 mg iron and 13 other micronutrient) does not improve growth, likely because of interactions involving zinc and iron, there is a need to show whether increasing the zinc content of MNP (relative to the iron dose) will improve growth outcomes in children.
• Furthermore, in light of growing concerns that the conventional anthropometric measures are not sensitive indicators of growth rate, there is a need to explore the use of growth biomarkers, such as growth hormones in defining growth status, growth potential and response to micronutrient supplements.
• Therefore, this study was designed to evaluate the comparative benefits of preventive zinc supplementation alone versus a high-zinc MNP on plasma concentration of IGFBP3 and IGF1, and to determine whether IGFBP3 and IGF1 mediates the growth response to zinc and MNP.
• Compared to the placebo control group, IGFBP3 and IGF1 concentrations after 36 weeks of supplementation will be higher in both PZ and MNP groups, controlling for baseline values.
• A positive response in IGFBP3 or IGF1 will be associated with a higher linear growth rate and reduced stunting prevalence in the MNP and PZ groups relative to the placebo group.
• A double-blind, placebo controlled, randomized trial investigating the comparative growth benefits of daily supplementation for 36 weeks with zinc supplementation (7 mg/d) versus daily MNP (containing 10 mg zinc) among rural Laotian children. Analyses of baseline and endline plasma IGF1 and IGFBP3 concentration in the placebo (n=140), PZ (n=140) and MNP (n=140) groups.
• By showing a positive impact of this novel MNP formulation (containing 10 mg Zinc) on growth, IGF1 and IGFBP3, our study has the potential to a) guide MNP programs in low income settings and b) increase awareness among researchers about the usefulness of IGF1 and IGFBP3 in defining growth status and potential.
Website Link: https://picn.ucdavis.edu/people/maxwell-barffour