Dude

Trying to hold it in leads to a build up of pressure and major discomfort. A build up of intestinal gas can trigger abdominal distension, with some gas reabsorbed into the circulation and exhaled in your breath. Holding on too long means the build up of intestinal gas will eventually escape via an uncontrollable fart.

The research is not clear on whether the rise in pressure in your rectum increases your chance of developing a condition called diverticulitis, where small pouches develop in the gut lining and become inflamed—or whether it doesn’t matter at all.