How much does an empty colon weight?

About 250-350 gm: At autopsy, especially in people who have been very sick and not eaten, it's not uncommon to feel an empty colon. We usually do not weigh it, but this is my recollection, allowing for the usual amount of fat in the appendices epiploica but removing the mesentary at its junction.

Maybe 1#: Can't say that i remember this question from anatomy class but a quick online search suggests that an empty colon (large intestine) weighs ~1# while it can contain 3-4# of you know what. With that said, there's no proof that colon cleansing improves your health. Sure you need to clean your bowels before a colonoscopy but aside from that, plenty of fiber, fluids & exercise will keep stool moving.