Air gets into your system either through swallowing it or from bacteria breaking down undigested food in the large intestine. You can swallow air while drinking water, especially if you're trying to drink too much too fast.
Drinking More Water Can Ease Gas
As long as you're careful not to swallow air while drinking, having an extra cup of water can actually help reduce the amount of gas you experience. Staying hydrated and keeping water flowing through your system aids in digestion and can prevent and reduce gas in the digestive tract. You can also reduce excessive gas by taking herbs that aid in digestion, like peppermint, ginger, chamomile and fennel seeds. Try drinking a glass of water with a drop of peppermint oil.
Effects of Drinking Too Much Water
According to an article published in "Scientific American" in 2007, drinking too much water within a short period puts stress on your kidneys, brain and other organs. Symptoms of water intoxication can include fatigue, nausea, vomiting, headaches and mental disorientation. You'd have to drink a great deal of water in a very short time to experience water intoxication. The best way to make sure you're getting the right amount of water is to drink according to your thirst, drink when you sweat and don't drink too much at once to avoid shocking your organs.