[Association between frequency of fruit and vegetable intake and chronic obstructive pulmonary disease]

To explore the association between frequency of fruit and vegetable intake and chronic obstructive pulmonary disease (COPD).

In 2007, 48 974 Chinese residents aged 15 - 69 years were selected as study participants by multistage stratified proportionate to size random sampling from the 161 sites of Disease Surveillance Points System. Standardized questionnaires were used to collect relevant information to compare the risk for self-reported physician diagnosed COPD between different frequency groups for fruit (< 2, 2 - 4, 5 - 7 d/week) and vegetable (< 4, 4 - 5, 6 - 7 d/week) intake.

The proportion of vegetable intake was 89.9% (44 019/48 974) and 4.6% (2262/48 974) for individuals with frequency of 6-7 and < 4 d/week respectively. The proportion of fruit intake was 30.8% (15 072/48 974) and 31.5% (15 432/48 974) for individuals with frequency of 5 - 7 and < 2 d/week respectively. The prevalence of self-reported COPD was 2.9% (1412/48 974). After adjusting for age, sex, urban/rural areas, passive smoking exposure and family history, the risk of COPD decreased among those with high frequency (5 - 7 d/week) of fruit intake (OR = 0.80, 95%CI: 0.66 - 0.98 for never smokers; OR = 0.80, 95%CI: 0.64 - 0.99 for ever smokers), compared to subjects with low frequency of fruit intake (< 2 d/week). Among never smokers, those with high frequency of vegetable intake (6 - 7 d/w) had a low risk of developing COPD (OR = 0.65, 95%CI: 0.48 - 0.89).

There were beneficial effects of fruit and vegetable intake on COPD.