Nutritional Epigenetics of Vitamin Intake (A, B1, B2, B3, B6, B12, and E): Associations with Genome-Wide DNA Methylation.

BACKGROUND/

OBJECTIVES

DNA methylation is a key epigenetic mechanism involved in gene regulation and chromatin stability and may be influenced by nutritional exposures. However, population-level evidence regarding associations between dietary vitamin intake and genome-wide DNA methylation remains limited.

METHODS

We investigated associations between dietary intake of vitamins A, B1, B2, B3, B6, B12, and E and blood DNA methylation in 2030 participants from the Southern Community Cohort Study (SCCS). Dietary intake was assessed using a validated Food Frequency Questionnaire, and genome-wide DNA methylation was profiled using the Illumina Infinium MethylationEPIC v2.0 BeadChip. Epigenome-wide association analyses were conducted using robust linear regression models adjusted for demographic, lifestyle, and estimated cellular composition variables.

RESULTS

We identified 34 CpG sites associated with dietary intake of vitamins B1, B2, B3, B6, and E, at a false discovery rate-adjusted p-value (FDR_p) threshold of <0.1. The strongest association was observed between vitamin B6 intake and cg19831775 (Beta = -0.111, FDR_p = 0.015). No statistically significant associations were identified for vitamins A and B12. Most observed effects were modest, and associations were locus-specific rather than global. Race- and sex-stratified analyses demonstrated generally consistent directions of association, although statistical significance was attenuated in subgroup analyses.

CONCLUSIONS

These findings provide suggestive evidence that dietary intake of vitamins B1, B2, B3, B6 and E may be associated with subtle variation in DNA methylation at specific genomic loci.