The short answer to this question is “yes,” but the longer answer is a bit more complicated. While a 2009 report put out by the Departmental of Clinical and Experimental Medicine at the University of Naples claims that “Most of the CO2 in a carbonated beverage does not actually reach the stomach,” both the Mayo Clinic and Johns Hopkins Medicine say that carbonated beverages can increase gas in the digestive system. The answer gets more intricate when you add sugar and artificial sweeteners into the mix. If you find that you’re increasingly bloated after drinking diet soda, it may be because some artificial sweeteners can also cause excess gas. An overabundance of high-fructose corn syrup — which is found in many “regular” sodas — may also lead to gas and bloating.