As someone who's done LF's it caught my attention a few months ago when I read that bile, when it reaches the colon, turns carcinogenic. Don't remember which website I was on, but here are a couple of other sites saying similar things:
It has been known for quite a long time that an excess of bile release in to the intestines can increase the risk of intestinal cancer. For example, when someone has had their gallbladder removed. Normally the gallbladder will control the release of bile by squirting out small amounts of bile in doses dependent on oil/fat levels present. When the gallbladder is removed there is no longer a release of small amount of bile, and instead bile gets dumped in to the intestines. Bile is caustic though and will chemically burn the intestinal wall when larger amounts of bile enter the intestines. This chemical burning of the intestinal wall by the excess bile can lead to cellular damage and mutations that can result in cancer.