Conspiracy Theories

I was visiting with a very well meaning person today who mentioned that "Big Drug Companies" run the oncology departments and that the poison we get to "cure" the cancer is no better than certain herbs and spices (I can eat Kentucky Fried Chicken and get better)? I know I am simplifying things, but I have to think that if there was something so easy, the cure wouldn't be on some website or in a book, but would be national news.