Variations in oral bacteria linked with future risk of lung cancer in people who have never smoked, finds study This link between oral bacteria and lung cancer may not be that easily apparent but it’s based on an emerging scientific consensus that the oral microbiome has a huge role to play in lung health Representational image. Image courtesy: Pixabay/kalhh Lung cancer is the most common cause of cancer-related death among men and women worldwide. While a huge proportion of lung cancer cases occur due to tobacco use and smoking, a margin of this global disease also occurs in people who have never smoked in their lives. A 2007 study published in