Flatulence is the passing of gas from the digestive system. Medical literature describes flatulence as "flatus expelled through the anus". Flatus is the medical word for gas generated in the intestinal tract. Passing wind is a normal biological process, like sweating, burping or breathing. Everybody farts, even those who seem not to. The average human passes wind approximately 15 times a day. When we eat, drink or swallow saliva, we also swallow tiny amounts of air. This swallowed air accumulates in the gut. The gas within our digestive system consists mainly of nitrogen and oxygen. When we digest food, gas, mainly in the form of hydrogen, methane and carbon dioxide is released. As the gas builds up, the body may need to get rid of it - this is done by either burping or flatulence. Many times, flatulence occurs and the person is unaware of it - there is no smell, and the amount is tiny. When there is a smell, there are usually small amounts of sulfur gases. If food has not been digested properly, it starts to decompose releasing sulfur.
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