By itself, carbonated water appears to have little impact on health.[1] Carbonated water eases the symptoms of indigestion (dyspepsia).[2][3] Carbonated water may increase irritable bowel syndrome symptoms of bloating and gas due to the release of carbon dioxide in the digestive tract.[1] Some carbonated waters have added sodium, so they may be an issue for those on low-sodium diets.
Carbonated soft drinks such as colas do have health risks. Carbonated colas have a correlation with slightly decreased bone density in older women. Soft drinks are about 100 times more erosive to teeth than plain carbonated water