Gas collects in two main ways. Swallowing air while you eat or drink can cause oxygen and nitrogen to collect in the digestive tract. Second, as you digest food, digestive gases such as hydrogen, methane, and carbon dioxide collect. Either method can cause flatulence= mkusanyiko wa gas kwenye mfumo wa chakula.
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.
By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere