Re: Why single out bacon?
"Bacon is cured in salt (brine or dry salt)"
Some years ago I was on a course for familiarisation with Japan and Japanese culture for a large pharmaceutical company, during which they mentioned Japan has a higher than usual incidence of bowel and stomach cancer.
When I queried why this was the instructor said it was thought this was due to the amount of salt in traditional Japanese diets, a quick Google reveals there does seem to be a link between high salt intake and these types of cancer:
http://www.nature.com/bjc/press_releases/p_r_jan04_6601511.html