Biologically speaking, your body doesn’t care about bubbles. Water is water—those H2O molecules are identical whether they come from a stream or a SodaStream. Sparkling water hydrates you just as effectively as flat water. The carbon dioxide that makes it fizzy dissolves into carbonic acid, but your body simply processes it and expels it as burp exhaust.
In fact, multiple studies show that there’s no significant difference in hydration markers between still and carbonated water after exercise. So if you chug a can of LaCroix after a run, you’re not cheating. You’re just hydrating with a tiny bit of theatre—and honestly, who doesn’t love a little drama with their electrolytes?
But Wait—Doesn’t the Fizz Mess With Your Stomach?
Here’s where the story gets a little squishy, like a bloated belly after too much seltzer. Carbonated water can cause gas and bloating for some people. (Hi, Jenna.) The bubbles literally fill your stomach with air, which can make you feel full and a bit puffy. If you’re someone who already fights with indigestion or IBS, that fizz might turn hydration into a guessing game of “will I burp or will I bloat?”
But—and this is a big but—for the average healthy person, that discomfort is temporary and harmless. It’s not dehydrating you. It’s just giving your diaphragm a tiny work-out. Think of it as a core exercise for your esophagus. Glamorous, right?
