You might have been lead to believe by recent Cancer Research UK (CRUK) campaigns and from other equally reputable (and some probably less so) sources that we now have concrete evidence that being obese (in and of itself) is a cause of cancer; the way that we’re sure that smoking is. This though, is not a fact. Cancer is such an emotive topic and the causes, treatment and life-changing effects it can have are vastly complicated. But to link obesity and smoking together as equal causes of cancer is just wrong. Read more for why and what CRUK could have done better.