Natural sparkling mineral waters such as Perrier and San Pellegrino are not the same, these waters come from mineral springs and tend to contain minerals and sulfur compounds, these waters are often carbonated as well. Tonic water is also a form of carbonated water, but it contains a bitter compound called quinine and sugar or high fructose corn syrup.
Water and carbon dioxide react chemically to produce carbonic acid, this is a weak acid that has been shown to stimulate the same nerve receptors in the mouth as mustard to trigger a burning, prickly sensations that some enjoy and some are irritated by. If carbonated water has a pH of 3-4 it means that it also slightly acidic, but drinking these waters will not make the body more acidic. The kidneys and lungs remove excess carbon dioxide, this keeps the body slightly alkaline with a pH of 7.35-7.45 regardless of what you ingest.
There has been concern that these waters can damage the teeth since the enamel is exposed to acid, while there is little research on the topic one study found that these waters damaged enamel very little more than still water, and mineral water was 100 times less damaging that sugary soft drinks. The combination of sugar and carbonation on the other hand may lead to dental decay, while plain sparkling water appears to pose little risk.
Sparkling water may help to improve the swallowing ability in young and older adults by stimulating the nerves responsible for swallowing, one study showed the combination of carbonation and cold temperature strengthened these beneficial effects.
Sparkling water may help food remain in the stomach for longer, which can lead to a greater sensation of fullness, but more research is needed to confirm the results of smaller studies.
Those with constipation report that sparkling water helped to relieve their symptoms as participants in one study reported a 58% decrease in their symptoms, and there is evidence that sparkling water may help to improve other symptoms of indigestion. In another study those with chronic digestive issues reported significant improvements in symptoms after 15 days.
It has been said that carbonated beverages are bad for bones due to the high acid content, but research suggests this is not true, cola is the only beverage associated with significantly lower bone mineral density and carbonated water appears to have no effect on bone health.
Although evidence is limited carbonated water may help to improve heart health by decreasing LDL cholesterol and reducing inflammatory markers as well as blood sugar; estimated risk of developing heart disease within 10 years was decreased by 35% for those who drank carbonated water over those who drank control water.
Currently there is no evidence to support carbonated or sparkling water being bad for health; it is not bad for teeth and appears to have no effect on bone health. Evidence does suggest they may help to enhance digestion by improving swallowing ability and reduce constipation. If you enjoy these waters there is no reason to give them up, provided they have not been sweetened.
