Gas Also called: Belch, Burp, Eructation, Flatulence, Flatus Summary Everyone has gas. Most people pass gas 13 to 21 times a day. Passing gas through the mouth is called belching or burping. Passing gas through the anus is called flatulence. Most of the time gas does not have an odor. The odor comes from bacteria in the large intestine that release small amounts of gases that contain sulfur. Gas in the digestive tract comes from two sources: air that you swallow and the breakdown of undigested food by bacteria in the large intestine. Certain foods may cause gas. Foods that produce gas in one person may not cause gas in another. You can reduce the amount of gas you have by Drinking lots of water and non-fizzy drinks Eating more slowly so you swallow less air when you eat Avoiding milk products if you have lactose intolerance Medicines can help reduce gas or the pain and bloating caused by gas. If your symptoms still bother you, see your health care provider. NIH: National Institute of Diabetes and Digestive and Kidney Diseases National Institute of Diabetes and Digestive and Kidney Diseases Array Abdominal bloating Belching Bland diet Gas – flatulence Find an Expert American College of Gastroenterology American College of Gastroenterology Find a Gastroenterologist American College of Gastroenterology National Institute of Diabetes and Digestive and Kidney Diseases National Institute of Diabetes and Digestive and Kidney Diseases Start Here Belching, Bloating and Flatulence American College of Gastroenterology Gas and Gas Pains Mayo Foundation for Medical Education and Research Gas in the Digestive Tract National Institute of Diabetes and Digestive and Kidney Diseases What I Need to Know about Gas National Institute of Diabetes and Digestive and Kidney Diseases Children Burping Your Baby Nemours Foundation What’s a Fart? Nemours Foundation Why Do I Burp? Nemours Foundation Clinical Trials ClinicalTrials.gov: Flatulence National Institutes of Health Health Check Tools Excessive Gas DSHI Systems Living With Foods That May Cause Gas International Foundation for Functional Gastrointestinal Disorders Journal Articles Gas Treatments and Therapies Treatment of Gas International Foundation for Functional Gastrointestinal Disorders Reference Desk Your Digestive System and How It Works National Institute of Diabetes and Digestive and Kidney Diseases