What is the normal amount of gas in the intestine?
Body plethysmography and argon washout techniques have shown that the volume of gas in the intestinal tract is approximately 200 ml in the fasting and postprandial states. This is so, even, in individuals who complain of excessive gas. What is the composition of intestinal gas? Nitrogen (N2), oxygen (O2), carbon dioxide (CO2), hydrogen (H2) and methane (CH4) account for more than 99% of the expelled gas. Analysis has shown that nitrogen is the predominant constituent of intestinal gas. None of the principal constituents have odour. Foul odour is mainly due to sulphur containing compounds like hydrogen sulphide, dimethyl sulphide etc. Some amount of swallowed air also passes down from the stomach into the intestines over a period of time. How is gas passed from the intestine? Gas is released through mouth in the form of a burp/belch, or via the anus as flatus. A normal individual emits flatus about 12-25 times per day. Whatever gas is belched out is from exogenous source or swallowed ai
