Why flatulence happens?
When you swallow food, water or saliva, you also swallow small amounts of air, which collects in the digestive system. Gases can also build up when you digest food. The body needs to get rid of the build-up by farting (flatulence) or burping (belching). Sometimes you may not notice you have passed wind because most of the gases are odourless and often released in small quantities. Flatulence usually only has a bad smell if it contains gases that smell, such as sulphur. However, it's important to remember it's normal for the gas you pass to sometimes smell a bit. Excessive flatulence can be caused by swallowing more air than usual or eating food that's difficult to digest. It can also be related to an underlying health problem affecting the digestive system, such as recurring indigestion or irritable bowel syndrome (IBS).