Did hot dogs save us from colon cancer?

After 1978, two strangely related things happened: a new set of regulations for processed meat limited the amount of nitrite used in hot dogs, forcing manufacturers to add ascorbate or erythorbate instead. And the following that year, there was a major dropoff in colon cancer deaths. Now, researchers are questioning… » 10/27/11 4:00pm 10/27/11 4:00pm