Does Seltzer Water Dehydrate You. “science shows seltzer water is just as hydrating as regular tap water,” says jessica crandall snyder, rdn, registered dietitian nutritionist at vital rd in denver. That it can mess with your teeth, that it isn't as hydrating as flat water.

Not only is there zero evidence that sparkling water dehydrates you (why would it exactly?), it actually does the exact opposite (surprise!). Sparkling water is beneficial as well because naturally sparkling, mineral water contains minerals that get depleted during a workout. That it can mess with your teeth, that it isn't as hydrating as flat water.