Does Sparkling Water Hydrate As Well As Still Water?

Our collective love affair with sparkling water has recently caused us to ponder two questions: One, what percentage of our monthly grocery budget is now spent on La Croix? And two, is drinking fizzy water just as good for us as still water? The answer to the first is probably unsettling, so we'll skip that and focus on the second part.

"There isn't any research in this area, but theoretically carbonated water would hydrate the body in the same way as still water, and in some ways may be more beneficial because for individuals it may taste better, which would allow them to be consuming more water throughout the day," says Gabrielle Giersch, associate director of education at the Korey Stringer Institute at the University of Connecticut.

We can definitely attest to that: We're much more likely to reach for a can of Pamplemousse than a glass of room-temperature tap water during the work day. And when we say 'a can,' we mean three or four over the course of the day. Wait, is there such a thing as too many bubbles?

"For new sparkling water drinkers, they should be cautious with possible stomach discomfort related to carbon dioxide, which can cause excessive burping and gas. To my knowledge, there's no scientific literature to support the danger; it just might be uncomfortable," says Kristen Smith, a registered dietician and spokesperson for the Academy of Nutrition and Dietetics. For the same reason, she cautions against drinking sparkling water right before or during exercise. "Maybe start with smaller quantities and see how your body and stomach tolerate it."

Gas and stomach pain shouldn't be an issue for people who consume a normal amount of sparkling water throughout the day. Where it can become a problem, experts say, is if a person was trying to rehydrate very quickly after strenuous physical activity leading to dehydration. Because of the gas in carbonated water, the stomach likely can't hold quite as much of it as still water, making still water preferable for fast rehydration.

"As long as it's tolerated by the individual, consuming carbonated water after a workout would certainly allow for rehydration. But if someone is massively dehydrated it wouldn't be recommended after a workout," Giersch says.

So unless you've just run a marathon and need to get fluids in your body stat, it's probably just fine to reach for carbonated water. But be sure to read the labels on tonic water and at-home carbonation machine flavoring packets: Many of those contain salt or sugar, which can take away from water's hydration properties.