The Key to Avoidance

It seems like avoidance is one of the first keys to not getting sick and not getting a deadly disease. If you avoid people with the flu then your chances of getting it are far less than if you are around those who are in the infectious stage. The same goes for a cold and for lots of other obvious diseases and infections but what about the really big ones? What do you avoid to not get cancer? There are just too many things in our environment labeled as a carcinogen.