Highly processed and fast foods are a major contributor to the risk of bowel cancer, which kills 80 Australians every week. In fact we have one of the highest rates of bowel cancer in the world. Joe Avati investigates. Unless you're lactose intolerant, you'll probably drink around a hundred litres of cow's milk each year. But what is it you're actually drinking? Why doesn't milk taste like it used to when you were a kid? We also revisit the Heptinstall family to see the unexpected results of the World War 2 diet.