Overview
- The Thorax paper published June 30 analyzed two asthma cohorts—1,165 children in GACRS and 1,041 adults in ODOLLFA—and found higher circulating vitamin A was associated with larger FEV1 and FVC in both groups.
- In adults only, higher vitamin D levels correlated with modest improvements in FEV1 and FVC and with measures of slower epigenetic ageing derived from DNA‑methylation clocks.
- Mediation analyses implicated serum microRNAs and DNA methylation as partial mediators of the vitamin–lung function links, including reduced methylation at the IRF5 gene and shared miRNAs that regulate 248 inflammation‑ and lung‑function genes.
- The study is cross‑sectional, used relative quantification for vitamin A, lacked mRNA and repeated measures, and cannot establish causality; an accompanying editorial noted prior randomized trials of vitamin D did not reliably improve lung function.
- Authors and commentators call for replication in independent cohorts, longitudinal follow‑up and randomized intervention trials before changing clinical practice, and say the epigenetic findings could point to personalized‑nutrition or molecular therapy targets if confirmed.