How can I have cancer Doctor? I don t smoke I exercise every day I eat the right food and I get annual health check-up's. Bewildered and shocked patients often say this to me. The reality - no matter how many Do s and Don ts' we follow fossil fuel pollution food made from pesticide-laden agri-produce and stressful work lives are here to stay. These causes of cancer are beyond individual control and short of staying in a bubble they can t be avoided. Preventive health check-ups are good they serve a purpose but awareness and alertness is equally important.