[holland3r]

I used to work in a digestive cancers lab. Generally, if the blood is bright red there's nothing to worry about -- the blood is oxygenated and has therefore come from near the anus from like a fissure or hemorrhoid or something.

If the blood is dark, however, it has come from somewhere higher up in the intestine and could be a symptom of GI cancer or precursor legions -- oh noes!