The average person expels gas 14 times every day. The amount of gas released ranges from as little as one cup to as much as one half gallon per day. Gas is made primarily of odorless vapors such as carbon dioxide, oxygen, nitrogen, hydrogen, and sometimes methane. The unpleasant odor of flatulence comes from bacteria in the large intestine that release small amounts of gases that contain hydrogen sulfide.
Flatulence occurs when a food does not break down completely in the stomach and small intestine. As a result, the food makes it into the large intestine in an undigested state. Most lower intestinal gas is produced when bacteria in your colon ferment carbohydrates that are not digested in your small intestine. The body does not digest and absorb some carbohydrates (the sugar, starches, and fiber found in many foods) in the small intestine because of a shortage or absence of certain enzymes. This undigested food then passes from the small intestine into the large intestine, where normal, harmless bacteria break down the food, producing gases such as hydrogen, carbon dioxide, and, in about one-third of all people, methane. Eventually these gases exit through the rectum.
Author Frank Morosky is Vice President of Flat-D Innovations (www.flat-d.com), an FDA registered company that manufactures a flatulence (intestinal gas) deodorizing device, called the Flatulence Deodorizer, which will eliminate the odors associated with flatulence. The product is a thin (1/16th of an inch) activated charcoal fabric pad that is placed in the underwear next to the buttocks. Their products are commonly recommended by doctors.