Restaurants often offer mints to their patrons after a meal. This is an old tradition geared to reducing the chance of untoward gaseous emissions. Gas builds up in the intestine in various ways. Air can be swallowed. Carbon dioxide can be produced when the acid contents of the stomach mix with naturally occurring bicarbonate in the small bowel. Hydrogen and methane along with some odiferous sulfur compounds are produced by the action of bacteria on indigestible food components in the large intestine. The bottom line is that if there is a buildup of gas, it has to come out one way or another. Peppermint contains natural oils that act as a 鈥渃arminative,鈥� meaning that they allow sphincter muscles to relax so that gases can be expelled steadily rather than in powerful explosive bursts.
