Is sparkling water as hydrating as still water?

2026-10-30

Yes. Sparkling water is water with carbon dioxide dissolved in it, and your body handles it the same way as still water. In a controlled trial that compared a liter of different drinks, sparkling water was retained just as well as still water. So if bubbles help you drink more, count every glass toward your goal. The fine print is about other things: plain sparkling water is gentle on teeth, but flavored and sweetened versions are more acidic; the gas can make some people feel bloated; and some mineral waters contain a fair amount of sodium.

The evidence: bubbles don't change hydration

The best direct test comes from a 2016 study in the American Journal of Clinical Nutrition. Researchers gave 72 men one liter of one of thirteen drinks and measured how much urine they produced over the next four hours. The less urine, the more of the drink the body had kept. Sparkling water came out the same as still water. (Our article on whether other drinks count toward your water goal looks at the full list.)

That makes sense physiologically. The carbon dioxide mostly escapes as gas, from the glass or as a burp. What reaches your gut and gets absorbed is water, plus whatever minerals the brand contains.

Is sparkling water bad for your teeth?

When carbon dioxide dissolves in water it forms a weak acid, so sparkling water is slightly more acidic than still water. That's where the worry about enamel comes from.

For plain, unflavored sparkling water, the risk looks small. The American Dental Association's consumer site, MouthHealthy, reports that in a lab study on donated teeth, sparkling water and regular water had about the same effect on enamel, and concludes that sparkling water is generally fine for your teeth and far better than sugary drinks.

Flavored sparkling water is a different case. A 2007 lab study of flavored sparkling waters measured a pH between about 2.7 and 3.3 and found that they dissolved tooth enamel in the lab. The authors recommended treating them as acidic drinks rather than as water. Citrus flavors (lemon, lime, grapefruit) are the main culprits, because they contain citric acid. And versions with added sugar are sugary drinks, full stop.

Practical ways to protect your teeth:

Prefer plain sparkling water for most of your daily intake.
Drink flavored versions with meals or in one go, rather than sipping a bottle all afternoon. Frequent sipping keeps your teeth bathed in acid.
Have some plain still water too. The ADA recommends drinking fluoridated tap water, which helps protect against cavities.
Don't brush right after an acidic drink. Many dentists suggest waiting a while, so you don't brush softened enamel.

Bubbles and bloating

The gas has to go somewhere. The NHS lists fizzy drinks among the common causes of bloating because they add gas to your gut, and suggests limiting them if bloating bothers you. Some people also find that a large glass of sparkling water before a meal makes them feel full sooner, which can be either a perk or a nuisance.

If you're prone to bloating, reflux or irritable bowel syndrome (IBS), try:

choosing lightly sparkling water instead of strongly carbonated;
letting a glass stand for a few minutes so some of the gas escapes;
sipping rather than gulping, and skipping straws, which make you swallow more air;
switching to still water during and right before exercise, when a full, gassy stomach is uncomfortable.

If bloating is persistent or comes with pain, weight loss or changes in bowel habits, see a doctor rather than just cutting out bubbles.

Sodium and minerals in sparkling mineral water

Not all sparkling waters are the same. Some are tap or purified water with added carbon dioxide; others are natural mineral waters from a specific spring, sometimes naturally carbonated, with a mineral content that can be high.

In the EU, labels on natural mineral water follow fixed criteria set out in Directive 2009/54/EC:

"Suitable for a low-sodium diet": less than 20 mg of sodium per liter.
"Contains sodium": more than 200 mg of sodium per liter.
"Contains calcium": more than 150 mg of calcium per liter.
"Contains magnesium": more than 50 mg of magnesium per liter.
"Contains bicarbonate": more than 600 mg of bicarbonate per liter.

For context, the World Health Organization recommends that adults keep sodium below 2,000 mg a day (about 5 g of salt). A liter of low-sodium water adds almost nothing to that. A liter of a high-sodium mineral water can add a noticeable share, and if it's your main drink, that adds up over the day.

The minerals aren't bad in themselves. Calcium and magnesium in mineral water count toward your intake, and a bit of sodium after a sweaty workout is no problem. But if you've been told to limit salt, for example because of high blood pressure, heart failure or kidney disease, check the label and ask your doctor which waters are right for you. In the US, check the Nutrition Facts panel for sodium, since the EU label wording doesn't apply.

Does carbonation affect anything else?

You may have heard that fizzy drinks weaken bones. That concern comes mainly from colas, which contain phosphoric acid and often replace milk. Plain carbonated water is a different drink and isn't known to harm bones. Evidence here is limited, but there's no good reason to avoid plain sparkling water for your skeleton.

How to make sparkling water part of your routine

Use it to replace soft drinks. Swapping a daily soda for plain sparkling water cuts sugar without giving up the fizz.
Add flavor yourself. A slice of cucumber, a few mint leaves or a splash of juice gives taste without the acidity of commercial citrus flavors. More ideas in don't like plain water?
Make your own. A home carbonator with tap water is cheap and avoids plastic bottles. Our guide to tap vs bottled water covers safety and cost.
Count it like water. In Water Tracker, a glass of sparkling water is logged the same way as any other glass. One tap on the iPhone, the Apple Watch or a Home Screen widget, and it counts toward your daily goal.

Bottom line

Sparkling water hydrates just as well as still water, so if you prefer the bubbles, drink it without guilt. Plain sparkling water is fine for your teeth; flavored ones, especially citrus, are more acidic and best enjoyed with meals rather than sipped all day. If the gas bloats you, choose lighter carbonation or alternate with still water. And if you drink mineral water every day and need to watch your salt, check the sodium on the label.

This article is general information, not medical advice. If you have a health condition, are pregnant or take medication, ask your doctor how much you should drink.