Chen · Environment international 2022 · randomized controlled trial · n=43

Fish oil blunts lung function decrements induced by acute exposure to ozone in young healthy adults: A randomized trial.

Cited 29 times in the scientific literature.

Level 2 - randomized trial

Individual randomized controlled trial

PubMed 35850080 · doi:10.1016/j.envint.2022.107407 · record verified 2026-08-30

What was done

Forty-three healthy young adults (mean age 26 ± 4 years, 47% female) were randomized to receive 3 g/day of fish oil (FO), 3 g/day of olive oil (OO), or no supplementation (control) for 4 weeks. Participants then completed 2-hour chamber exposures to filtered air and 300 ppb ozone with intermittent exercise on two consecutive days. Spirometry, sputum neutrophil percentage, blood biomarkers, vascular function, and heart rate variability were measured, and effects were analyzed using linear mixed-effect models.

What was found

Ozone exposure reduced FVC, FEV1, and FEV1/FVC across all groups relative to filtered air. However, the FO group showed a blunted decline compared to control: the post-exposure decrease in FEV1 was 48% smaller in the FO group (-0.21 ± 0.27 L) versus control (-0.40 ± 0.34 L), and the decrease in FEV1/FVC was 70% smaller in the FO group (-1.4 ± 3.18%) versus control (-4.67 ± 5.0%). Sputum neutrophil responses immediately post-exposure did not differ between groups. OO supplementation blunted systolic blood pressure increases 20 hours post-exposure.

Why it matters

This study provides randomized evidence that dietary fish oil supplementation may offer protection against pulmonary function decrements induced by acute ozone exposure in young healthy adults.

Limits

The sample size is small (43 total participants divided across three arms). Findings in young, healthy adults cannot be directly generalized to vulnerable populations such as individuals with asthma or COPD, and the high-dose acute chamber exposure (300 ppb) may not reflect chronic, real-world ambient exposure.

Cited by