Gas forms in your digestive tract for two reasons: from the air that you swallow and from the breakdown of undigested food by the trillions of bacteria that live in your large intestine, according to the U.S. National Library of Medicine. “We all have bacteria in our gut, which produces gas—and it has to go somewhere,” Sophie Balzora, MD, gastroenterologist and assistant professor of medicine at NYU Langone Medical Center, tells SELF.
Whether you fart or burp, gas comes out of your body in one form or another. In fact, we all pass gas an average of up to 20 times each day, according to the Mayo Clinic. In most cases, the gas you expel from your body is odorless, a mix of carbon dioxide, nitrogen, hydrogen, and sometimes methane. Sometimes, however, the bacteria we mentioned release gases that include sulfur, which is the culprit behind the unpleasant odor associated with passing gas, according to Johns Hopkins Medicine.https://www.self.com/story/causes-of-excessive-gas