Even after kicking your soda habit like a champ, you might still find yourself craving carbonated drinks something fierce—not so much the sugary, caffeinated varieties, but the straight-up fizzy ones that are nothing more than water and bubbles (though you do love the occasional hint of fruit flavor when the mood strikes).

On the one hand, it’s easy to understand what makes sparkling drinks so compelling. You get to enjoy all of the perks of carbonated beverages without the unhealthy side effects that can come from drinking soda, so it feels like you’re cheating the system in a way. On the other, it’s just carbonation. So what is it about the fizz that leaves you ravenous for more?

Why Carbonated Drinks Are So Irresistible

As important as it is to stay hydrated, many of us find drinking water to be as boring as it gets, so adding carbonation to the mix breaks the monotony. “While a flat drink will hit your sense of taste (and, maybe, smell), when you add carbonation, you’re now engaging your eyes, ears, and sense of touch,” says Susan Bowerman, RD, registered dietitian for Herbalife Nutrition. These sensations may make carbonated drinks seem more thirst-quenching, and you more compelled to turn to them when you’re parched.

The sensation of carbonation tickling the tongue may amp up feelings of fullness, and give off a more satisfying vibe than plain water: Researchers in Japan compared feelings of fullness in a small group of women who were assigned to drink carbonated or plain water after an overnight fast, and found there were increased feelings of fullness and decreased feelings of hunger among the carbonated water group. After measuring electrical activity in the stomach, they concluded that the oral stimulation from the bubbles was responsible for the uptick in satiety. “I also suspect the bubbles take up some space in the stomach, aiding that feeling of fullness,” says Suzanne Dixon, a registered dietitian with The Mesothelioma Center in Orlando, Florida.

We may also seek out carbonated beverages instead of flat because they provide a non-threatening thrill, similar to our love for spicy foods. Research suggests that the sensation produced by the carbonation irritates pain receptors in the mouth, producing a mildly painful stimulus, says New York-based physician Aastha Kalra, MD. This signal hints at something dangerous, even though we know it’s really okay, says Bowerman.

There’s a rumor floating around online that sparkling water leaches calcium from your bones, and this deficiency somehow causes more fizzy drink cravings. “It’s a myth that a calcium deficiency would make a person crave carbonated beverages,” says Dixon. Certain types of carbonated drinks can worsen a calcium deficiency, but sparkling water isn’t one of them.

This is because it’s not the carbonation in these drinks that can lead to a calcium deficiency, but the phosphoric acid, found mainly in cola drinks and fruit punches (here’s a list of examples). “When a person consumes excess phosphoric acid in cola, the acid load needs to be buffered with ‘basic’ (alkaline) minerals,” Dixon explains. “Calcium is the most important acid-buffering alkaline mineral in the body. To do its job, calcium is pulled from our bones, as needed, to buffer against acid loads in the body.”

If we’re not scoring enough dietary calcium—and the nutrients needed to allow calcium to do its thing, like vitamin D and magnesium—we can get into a situation where more calcium is being pulled from our bones than is being replaced. Cue osteoporosis.

But this doesn’t mean that soda causes a calcium deficiency, it just means there’s a possible association. What’s more likely is that consuming a lot of soda leaves little room for other drinks, such as calcium-rich ones, says Bowerman, which could domino into an imbalance in the body.

The only unhealthy thing about craving carbonated drinks is satisfying them with sugar- or sodium-filled varieties, like soda, club soda, or tonic water. But if your go-to fizzy drinks are plain or flavored and unsweetened (LaCroix or similar), no need to fret, says Dixon. They actually hydrate you just as much as still water.

For those who crave the sugar fix as much as the bubbles, you can take a build-your-own-beverage approach to wean yourself off the stuff. Take your fave 100 percent fruit juice (orange or cranberry, for example) and mix it with plain sparkling water—50 percent juice, 50 percent water, suggests Dixon. Over time, you can slowly decrease the amount of juice and increase the sparkling water until you’re only adding a splash of juice, if any. It’s a tasty way to hydrate and enjoy some bubbles without all the sugar (and phosphorus) of soda.