A new study reports that making some small changes to your indoor environment, such as temperature, humidity and air pollutants, may help alleviate dry eye symptoms.

The prospective, cross-sectional study included 97 veterans with a wide range of dry eye metrics. Each subject was given a standardized questionnaire and dry eye signs were assessed with a standard examination.

The researchers found that humidity was associated with worse symptoms, inflammation, eyelid vascularity and meibomian gland dropout. Multivariate analyses revealed that particulate matter of 2.5μm or smaller was associated with dry eye metrics as well.

“When adjusting for humidity, this study found that increased particulate matter exposure was associated with worse dry eye metrics,” the researchers said. “Humidity was positively associated with dry eye metrics, potentially because higher humidity increases microbial growth and particulate matter size and mass.”