A cohort study on the relationship between vegetable intake and risks of lung cancer in the Tin Corporation (YTC) miners in Yunnan

OBJECTIVE: To understand the relationship between vegetable intake and risk of lung cancer in the Tin Corporation (YTC) miners in Yunnan. METHODS: The reproducibility and validity of frequency of vegetable intake in Food Frequency Questionnaire (FFQ) were studied and the correlations between different vegetable intake and frequency and lung cancer relative risk among high risk population of lung cancer by Chi-square, single- and multi-Cox regression were analyzed. RESULTS: Results showed that the reproducibility and validity of wax gourd, cucumber, spinach, wild celery, fresh bush pepper, fresh soybean, sweet potatoes, asparagus, fresh bamboo shoot were good (r = 0.20 - 0.33, P < 0.05); There were significantly different incidences of lung cancer in different frequencies of wax gourd, cucumber, wild celery, fresh bush pepper out of 11 vegetables intake, and also in different total vegetable intakes (chi(2) = 8.83 - 30.64, P < 0.05). 11 vegetables and total vegetable intake were significantly negatively correlated with risks of lung cancer (RR < 1, P < 0.05). Only 2 vegetable frequencies were negatively correlated with risk of lung cancer by adjusting confounders such as age, occupational history, and smoking (P < 0.05). CONCLUSION: This suggested that vegetables intake may have a role in decreasing the incidence of lung cancer.