Air pollution could be associated with reduced lung function, and higher fruit intake may be linked with a smaller decline among women, according to a cross-sectional analysis of UK Biobank patients.

Each 5 µg/m³ increase in particulate matter sized 2.5 µm or less in diameter (PM2.5) was associated with lower forced expiratory volume in 1 second (FEV1). Patients reporting the highest fruit intake experienced the smallest decline, while those with the lowest intake had the greatest loss. The modifying effect was observed among women, who on average consumed more fruit than men.

Researchers also examined diet quality using a healthy diet score. Patients in the highest tertile had higher FEV1 compared with those in the lowest tertile. No interaction was observed between the diet score and air pollution, indicating that fruit intake specifically, rather than overall diet quality, was linked with the lung function differences. Across all diet categories, air pollution was consistently associated with poorer lung function.

The analysis included approximately 150,000 patients with complete data. Lung function outcomes were FEV1 and forced vital capacity (FVC). The researchers used linear regression models that adjusted for sex, age, height, body mass index, income, education, alcohol use, smoking, passive smoke exposure, physical activity, and ethnicity. Annual average air pollution exposures were assigned to patients’ residential addresses using 2010 data from the EXPANSE project.

The study had limitations. As a cross-sectional analysis, it didn't establish causality. Diet information was self-reported and subject to recall bias. Air pollution exposure estimates were based on residential address and may not have reflected individual variation in exposure. The findings were presented as conference data and hadn't yet undergone peer-reviewed publication.

“In this large study, total fruit intake seems to mitigate adverse effects of PM2.5 on lung function, with the group of highest fruit intake having the lowest PM2.5 related reduction in lung function,” said lead study author Pimpika Kaewsri, PhD, of the Centre for Environmental Health and Sustainability at the University of Leicester, and colleagues.

Source: ERS Congress 2025