Carbonated water is slightly acidic, and flavored carbonated water slightly more. On the whole, however, it’s not bad for you - indeed, it’s probably good for you, as your body needs minerals from water.
Carbonated water is full of little bubbles. Those bubbles create small amounts of carbonic acid in the mouth. There’s some concern that the carbonic acid is harmful to your teeth.
And there's a grain of truth to that concern: the carbonic acid is slightly worse for your teeth than drinking regular water. It's several steps below soda, however. The acidity of mineral water is more or less on par with fruit juice. Devoted carbonated water drinkers may be putting themselves at risk of a slightly increased risk of cavities, but moderate consumption is probably fine. If you do drink a lot of carbonated water, you can further guard against slight damage to your teeth by accompanying your carbonated water with some food, not swishing the mineral water around in your mouth, or rinsing with non-carbonated water after. One paper in the Journal of Oral Rehabilitation actually suggested that the mineral content of carbonated water may balance out against the damage that the carbonic acid does to the teeth. That theory, however, has not yet been fully borne out in the literature.
An important point to note is that flavored carbonated waters are slightly more corrosive than their non-flavored cousins. You're doing a little bit more damage to your teeth by drinking LaCroix - somewhere on the order of drinking lemonade instead of orange juice. This effect is described in a Birmingham School of Dentistry paper. Another consideration is that almost everything you eat or drink is either acidic or basic; carbonated waters are not unique in that regard. Everything you eat or drink has a slight effect on the integrity of your enamel, and the acidity of carbonated water should be considered in that context.
Another mineral water fear swirling in the health blogosphere is that it does damage to your bones. The specific concern is that mineral water leeches important nutrients, like calcium, thereby increasing your risk of osteoporosis. This may be connected to a lazy interpretation of a study published in the Journal of Adolescent Health published in 1994 which described higher rates of bone fractures in girls who consumed more cola beverages. That study did not find a similar effect with non-cola carbonated drinks.
Those findings were borne out by a 2000 study in the Archives of Pediatric and Adolescent Medicine and another from 2003 in the Journal of Bone and Mineral research. A 2006 paper published by a team of Tufts researchers described a similar effect for osteoporosis - that drinking cola increased the risk, especially for women, but that carbonated water did not. Another study found that drinking carbonated beverages increased urinary excretion of calcium - but that the effect was confined to caffeinated beverages. In carbonated beverages without caffeine (like mineral water), there wasn't more calcium in the urine.
Ironically, drinking de-mineralized water may have the leaching effect that's erroneously attributed to mineral water. A 2004 white paper from the WHO says that populations drinking de-mineralized water - either from desalination plants or via filters at home - had lower rates of absorption for calcium, magnesium, and other essential nutrients. Although they cautioned that more research was needed to establish medical consequences for this lower absorption, the studies they cite suggest that it may increase risk for heart disease, diabetes, and other chronic conditions. A study in the Journal of Endocrinology found that drinking mineral-rich water, by contrast, guarded against blood sugar spikes after eating fructose-rich foods and blunted the associated risk of chronic conditions like heart disease and diabetes.
More research is still needed. But it seems that de-mineralized water is wanting in the nutrients and minerals our bodies expect. Drinking tap water will provide for 15% of your daily calcium needs; de-mineralized water is lacking in that calcium and will absorb it from your body before it enters your bloodstream.
There are some legitimate medical conditions that would make drinking carbonated water a bad idea. If you suffer from irritable bowel syndrome, you might want to consult with your doctor before drinking a case of La Croix. IBS can make it difficult for the bowels to pass gas regularly. Drink enough mineral water and that gas could accumulate in your gut, causing uncomfortable ballooning, or give you a bad case of flatulence.
Possible short-term side effects
- carbonic acid can do slight damage to teeth
- may interact with ibs or other gastrointestinal conditions
Ingredients to be aware of
- sodium (some brands)
- artificial sweeteners (some brands)
- calories (some brands)
- some enjoy the taste more than still water
- improved indigestion
- guards against blood sugar spikes
- provides your body with essential nutrients