胃肠道经常有气,但一般不易觉察到,只有在向上嗳气(俗称“打嗝”)或向下排气(放屁)时才感觉到它的存在。胃肠道内的气体有两种:一种是随着日常吞咽动作(包括吃饭、喝水、吞咽唾液等)而进入胃肠道的气,这种气是没有气味的;另一种是食物在胃肠道内消化吸收过程中所产生的气,尤其一些吸收后剩余的食物残渣,通过在大肠内繁殖的细菌酶解作用产生的气体,这种腐败、发酵所产生的气体,则往往是有气味或带恶臭。尽管胃肠道内产生或 Gastrointestinal tract often have gas, but generally not easy to detect, only in the upper air (commonly known as “burp”) or down (fart) feel it when there is. Gas in the gastrointestinal tract, there are two: one is with daily swallowing (including eating, drinking water, swallowing saliva, etc.) and enter the gastrointestinal gas, this gas is odorless; the other is food The gas produced during the digestion and absorption in the gastrointestinal tract, especially some residual food residue after absorption, is produced by enzymolysis of bacteria that multiply in the large intestine, and the gas produced by fermentation is often odorized Or with bad smell. Although produced in the gastrointestinal tract or