# Heterogeneous impact of tea consumption on COPD risk in smokers: insights from the PIFCOPD study

## TL;DR

This study finds that tea consumption may protect smokers from COPD, but the effect depends on tea type and frequency.

## Contribution

The novel finding is that fully fermented tea reduces COPD risk in smokers, while jasmine tea increases it.

## Key findings

- Fully fermented tea consumption is linked to a 79% lower COPD risk in smokers.
- Jasmine tea consumption is associated with a 99% higher COPD risk in smokers.
- Tea's protective effect is strongest when consumed ≥7 times/week for ≥10 years.

## Abstract

Chronic obstructive pulmonary disease (COPD) is a highly prevalent disease worldwide, with smoking identified as the main risk factor. Emerging evidence suggests that tea consumption may confer protective effects on lung health. However, it remains unclear whether tea consumption can mitigate the adverse effects of smoking on COPD risk. This study aimed to investigate the association between tea consumption and COPD risk, and to examine whether this association differs by smoking status.

The Predictive Value of Inflammatory Biomarkers and Forced Expiratory Volume in 1 s (PIFCOPD) study is a multicenter prospective cohort (2018–2021) involving 7,252 participants (6,855 with normal lung function; 397 with COPD). Data on demographic characteristics, smoking status, and tea consumption were collected. Logistic regression analysis was used to assess the association between tea consumption and COPD risk. Interaction and stratified analyses based on smoking status were performed.

The proportion of tea consumption was 20.9% in the normal lung function group and 24.4% in the COPD group, with no significant difference. Tea consumption was not associated with COPD risk in the general population. However, interaction and stratified analysis based on smoking status showed that fully fermented tea consumption was associated with a protective effect against COPD in smokers (OR 0.21), especially when consumed ≥ 7 times per week and for ≥ 10 years. In contrast, jasmine tea emerged as a potential risk factor (OR 1.99), especially when consumed for ≥ 10 years.

In the general population, the effect of tea consumption on the prevalence risk of COPD is significant only in smokers, and this effect is modulated by the type, frequency and duration of tea consumption.