Overview
- The analysis, published June 30, examined two asthma cohorts totaling about 2,200 people and found higher circulating vitamin A tied to better lung function in both children and adults while higher vitamin D was linked to modest lung gains in adults only.
- Researchers measured plasma or serum vitamins, blood microRNA profiles, and DNA methylation and reported that some miRNA changes and reduced methylation at the IRF5 gene partially mediated the vitamin–lung function associations.
- Effects differed by age group with no clear vitamin D association in the child cohort and an adult vitamin D threshold near 30 ng/ml associated with small lung-function and slower epigenetic ageing signals.
- Study authors and editorialists stressed the work is observational with key limits including relative vitamin A quantification, lack of mRNA and longitudinal data, and the inability to prove cause which means the findings do not justify recommending supplements.
- Investigators call for replication, repeated measures, mechanistic mRNA work, and randomized trials to test whether altering vitamin A or D levels can improve lung function or slow biological ageing in people with asthma.