A study of two asthma cohorts found that higher vitamin A levels were associated with improved FEV1 and FVC in both children and adults with asthma. Previous evidence established that vitamins A and D play important roles in lung development, immune regulation, and asthma. However, how these vitamins influence lung function at the molecular level remained unclear.1
The recent investigation examined whether vitamin A and D levels were associated with lung function in people with asthma and whether epigenetic mechanisms, such as DNA methylation and microRNA regulation, could explain these associations.1
The study included 1,165 children from the Genetic Epidemiology of Asthma in Costa Rica Study (GACRS) and 1,041 adults from the Omic Determinants of Longitudinal Lung Function in Asthma (ODOLLFA) cohort from the Mass General Brigham Biobank. The study evaluated associations between vitamin levels and lung function measures, including FEV1, FVC, and FEV1/FVC. The researchers analyzed DNA methylation and circulating microRNA profiles to identify potential regulatory pathways associated with vitamin levels and lung function.
Rinku Sharma, PhD, Instructor at Harvard Medical School and Investigator at Brigham and Women’s Hospital, said the results demonstrated that, in children, higher vitamin A was associated with higher FEV1 and FVC but lower FEV1/FVC; vitamin D showed no association. In adults, both vitamins were positively associated with FEV1 and FVC; no significant association with FEV1/FVC was observed for vitamin D.
“More importantly, we found evidence that these relationships may involve epigenetic regulation through DNA methylation and microRNAs,” Dr. Sharma said. “One particularly interesting finding was a regulatory region near the IRF5 gene, where methylation patterns were consistently associated with vitamin levels across children and adults. These epigenetic patterns were also associated with lung function and measures of biological aging.
“So the study moves beyond simply asking whether vitamins are associated with lung function; it begins to provide insight into how nutritional status may be connected to molecular pathways involved in asthma and lung aging.”
Because this study was observational, it could not establish that supplementation would improve lung function. Rather, Dr. Sharma said, the findings suggest that vitamin status may be an important component of lung health and asthma biology and also that nutritional factors may interact with molecular pathways involved in inflammation and aging.
Clinically, this supports further investigation into whether maintaining adequate nutritional status could improve respiratory health, particularly in specific patient populations, she said. It also points toward a longer-term possibility of using molecular information—such as epigenetic signatures—to identify individuals who might respond differently to nutritional or other preventive interventions.
Richard Barbers, MD, FCCP, Professor of Medicine and Thoracic Surgery at Keck School of Medicine at the University of Southern California, said that defining the populations affected by vitamin deficiencies would have major health benefits, especially for women, children, patients older than 65 years of age, and those who are obese.
“The health benefits of good nutritional/vitamin status are well-publicized,” he said.
However, Dr. Barbers noted several limitations, including the higher proportion of women in the adult group, which could reflect selection bias. The adult cohort also included a large group of people with smoking history, as well as many participants with unknown smoking history, which could affect the results.
References
1. Sharma R, Kachroo P, Mendez KM, et al. The impact of vitamins A and D on lung function and regulatory epigenetics in adult and childhood asthma. Thorax. Published online June 30, 2026. doi:10.1136/thorax-2025-223756
