Why does shit smell bad?

The bacteria inside of the feces is what makes them smell so bad. Specifically, the bacteria produce various compounds and gases that lead to the infamous smell of feces. Just in case you were wondering, you can get very sick by eating feces because it contains so many types of bacteria and other harmful substances such as parasites. So I wouldn't suggest adding poop to your diet any time soon.

Poop will vary in smell depending on the type of foods and drinks that you consume. Generally speaking, feces will smell worse if you consume foods or liquids with many artificial flavors or chemicals in them. The bad smell of feces will usually be reduced by eating more natural foods that do not contain any artificial flavors or chemicals. Also, the poop of meat eaters usually smells worse than that of vegans.