Coffee and tea consumption and risk of lung cancer: A dose–response analysis of observational studies

Abstract Results from the recent meta-analysis suggested a favorable effect of green tea consumption and risk of lung cancer, while no significant association was found between black tea consumption and risk of lung cancer. Besides, a significantly positive association was found between coffee consumption and risk of lung cancer. However, the relationship of green tea and coffee consumption is unclear. Thus the dose–response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression. Results suggested that a linear dose–response relationship exists between coffee consumption and risk of lung cancer, while the dose–response relationship is nonlinear between green tea consumption and risk of lung cancer.