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Whether you prefer purified water, spring water or sparkling water, there's good news: All of these help keep your body hydrated. If you've ever wondered if carbonation affects the body's ability to absorb water, it doesn't. The key to ensuring your water-based beverage provides optimal hydration is to avoid waters with sugars and other additives that may not benefit the body.

Carbonated Water Comparisons

While sparkling water contains carbonation, the term "carbonated water" encompasses a handful of other beverages as well, such as tonic water, seltzer and club soda.

  • Seltzer water, sometimes called sparkling water, is still water with carbonation added. There are no added minerals in this type of bottled water, although some companies offer flavored versions. As with most carbonated waters, seltzer has zero calories. 
  • Sparkling mineral water refers to water that's naturally carbonated. It comes that way from its source, a mineral spring. As the name implies, this type of water also contains naturally occurring minerals that vary from source to source. Some brands may also add more carbon dioxide to make the drink fizzier. 
  • Club soda contains added carbon dioxide to give it fizz. It also contains added minerals such as salt and sodium bicarbonate, which gives it a slightly salty taste. It also has zero calories. 
  • Soda water means different things to different people, although it's always a fizzy water. Some say that soda water and club soda are the same, while others believe that soda water is the same as seltzer water, with no added minerals. Asking for soda water at a restaurant may net you either type of beverage. 
  • Tonic water is a lot like club soda in that it has added carbonation and minerals. That's where the similarity ends, however. Tonic water also contains quinine, which makes it bitter, plus sweetness from either corn syrup or sugar to combat the bitterness. This is the one type of carbonated water that contains calories. The calorie content varies by brand.  

Best Waters for Hydration

As far as hydration is concerned, the fewer the ingredients in the water, the better. Plain, still water, whether from the tap, a purifier or a spring, is ideal for hydration. If you want a fizzier water, seltzer water is ideal, as it has nothing added beyond carbon dioxide. Club soda and soda water are also good at hydrating, although these may contain some salt.

Sparkling water is beneficial as well because naturally sparkling, mineral water contains minerals that get depleted during a workout. Sodium is one such mineral that the body loses through sweat; the salt in sparkling water or club soda helps replenish some of that, although the amount of salt in this water is usually minimal. This is why many electrolyte beverages contain some salt.

That being said, the amount of sodium or salt in a bottle of sparkling water varies greatly from one brand to the next. French brand Badoit, for instance, contains up to 11 times the amount of salt found in tap water. Several other brands, such as Highland Springs and Perrier, contain less salt than the typical tap water. If you're concerned about salt intake, compare the nutritional information on several brands before purchasing a sparkling water.

Cause for Discussion

Many discussions online question whether sparkling water is as hydrating as still water. The key takeaway from medical research in Japan is that some adults are less likely to drink as much water if a carbonated water is the only option. They reported feeling fuller, largely due to the fizzing effects of the carbonation.

Children in one study hydrated more when they had access to a home carbonation machine, which could be because of its novelty, paired with the fact that many kids enjoy fizzy drinks and the burping that follows a generous gulp.

Equal amounts of still and carbonated water have essentially equal abilities to hydrate, as long as the carbonated water has no other potentially detrimental additives. Tonic water is the one fizzy water that you shouldn't use to hydrate due to its added sugars. Sugary beverages, especially if consumed regularly, could reduce the amount of water your body retains, essentially contributing to dehydration.