Let’s address the rumor head-on: does seltzer water actually dehydrate you? The short answer is no, but the long answer is a bit ironic—and honestly, kind of funny. Your body is smarter than the internet gives it credit for. Think of seltzer as fancy tap water with a little extra fizz; it’s still 99.9% H₂O, just with bubbles that tickle your nose.
The dehydration myth likely comes from two places: the carbonation itself and the “acid” panic. Sure, carbon dioxide creates carbonic acid, which gives seltzer a slightly lower pH than still water—but your stomach acid is way stronger (hello, pH of 1.5 to 3.5). That tiny bit of acid is a neutralized non-event once it hits your gut. (You know what’s actually dehydrating? That third beer you had before the seltzer. Oof.)
