Look to see whether your poop floats or sinks. The buoyancy of your poop lets you know whether your absorbing nutrients properly. Healthy poop should sink. Malabsorption can cause poops to float. Too much gas in the poop will also cause it to float. Foods that cause gas such as beans and cruciferous vegetables may be the culprit. While an occasional floating poop is not cause for alarm, if you have not changed anything in your diet and your poop starts floating regularly, seek medical advice.