The results from an extensive long-term study examining the link between fruit and vegetable consumption and lung cancer have shown that fruit and vegetables not only reduce the risk of lung cancer in non-smokers but in smokers too. The more you eat, the better you are protected!
Büchner et al., 2010. Fruits and vegetables consumption and the risk of histological subtypes of lung cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC). Cancer Causes and Control. 21(3) 357-371.