Serum Vitamin A in Relation to Genomic Biomarkers in Children: A Prospective Study

Background/Objectives: Vitamin A (VA), which is fat-soluble, belongs to the group of carotenoids, a class of highly effective antioxidant and genoprotective compounds (including astaxanthine, zeaxanthine, luteine). It plays a critical role in cellular growth, differentiation, and oxidative stress regulation, but prospective evidence linking childhood VA to subsequent genomic stability is scarce. This study investigated whether baseline VA levels were associated with later measurements of relative telomere length (RTL), four ribosomal DNA copy numbers (rDNA-CN: 5S, 18S, 28S, and 45S), and mitochondrial DNA copy number (mtDNA-CN) in children over a 4-year follow-up.

Methods

Baseline VA levels were measured in 2021. In 2025, peripheral blood genomic DNA was extracted, and RTL, rDNA-CNs, and mtDNA-CN were quantified using qPCR. Multivariable linear regression and restricted cubic spline regression (RCS) were employed to examine the associations and dose–response shapes. Sex-stratified analyses with interaction tests were performed to evaluate effect modification by sex.