Carbonation Carbonation comes from dissolving carbon dioxide in water, a process also used for sparkling waters as well as soft drinks. In addition to the pleasing sensory effect, carbonation is beneficial--it keeps beverages safe from bacteria and microbes. The results of carbonation when a beverage is opened or poured are quite obvious. In the body, the carbon dioxide (CO²) in a carbonated beverage is readily and rapidly absorbed through the wall of the gastrointestinal system. But not all of the CO² originally in the drink actually gets to the stomach. Some is lost in the fizz of opening the can or bottle, and some may combine with swallowed air to cause a belch. The truth is, most CO² in the beverage typically doesn't reach the digestive tract. The amount that does arrive there is quickly absorbed. In the process, it also enhances the absorption of the liquid that contains it, which causes the gastrointestinal tract to empty at a faster than usual rate. This helps to account for the long-time belief, recorded as early as 1914, that carbonation can promote digestion and ease nausea. Most of the CO² goes into the bloodstream, where the majority of it is carried to the lungs for exhalation. Most of the CO² in our blood is produced not by carbonated beverages, but by the body's conversion of carbohydrates, proteins and fats into energy. In other words, having CO² moving through the blood is a routine metabolic action.