For hydration there is no meaningful difference: unsweetened sparkling water counts toward your daily fluids too. The choice comes down to what suits you — digestive comfort, taste, and which one helps you drink regularly.
Hydration
Sparkling water is water with dissolved carbon dioxide. It supplies fluid just like still water, so unsweetened sparkling water counts toward your daily balance. There is no reason to treat it as inferior — as long as it contains no sugar or sweeteners you want to avoid.
Digestion and bloating
Carbon dioxide can cause burping and a feeling of fullness, especially if you drink quickly or have a sensitive digestive system (for example reflux or irritable bowel syndrome). There is no convincing evidence that unsweetened sparkling water harms healthy people. If it makes you uncomfortable, simply choose still water or one with less gas.
Teeth
Dissolved carbon dioxide slightly lowers the water’s pH. Studies of dental erosion, however, indicate that mineral waters, including sparkling ones, are much less harmful to enamel than sugary and acidic drinks (such as cola or juices). The risk rises when a drink contains sugar or acids (for example citric acid) — which also applies to “flavoured sparkling water”. Tips: drink with meals, do not sip one drink for hours, and do not brush your teeth right after an acidic drink.
Mineral content
Mineral water can contain calcium, magnesium, bicarbonate or sodium — in very different amounts. EU rules require the composition of mineral waters to be shown on the label. There is no single “best” water: if you limit salt, look at the sodium content; calcium and magnesium in water can be a small addition to your diet but will not replace balanced food.
“Water-like” drinks with additives
A fizzy drink is not the same as sparkling water. Flavoured waters, lemonades and “fit” drinks may contain sugar, sweeteners and acids. Read the label: if the ingredients include anything beyond water, carbon dioxide and perhaps a flavouring, treat it as a drink rather than water.
Practical buying tips
- check the mineralisation (mg/L) and sodium on the label,
- choose water without sugar or sweeteners,
- compare price and the convenience of packaging — for many people tap water is a cheaper, convenient option (check your local water supplier’s information),
- choose the water you actually like to drink — consistency matters more than type.
How much to drink through the day: How Much Water Should You Drink Per Day?. For help remembering, see How to Remember to Drink Water.
Frequently asked questions
Is sparkling water less hydrating?
There is no evidence that unsweetened sparkling water hydrates worse than still water. The difference is mostly in how it feels.
Is sparkling water bad for bones?
There is no convincing evidence that unsweetened sparkling water harms bones in healthy people.
Is sparkling water bad for the stomach?
For most healthy people no, but for some it increases burping, bloating or reflux symptoms. If that applies to you, choose still water.
Which water for children?
Usually plain still water; for mineral waters follow the manufacturer’s information and your paediatrician’s advice.
Sources
- Parry J. et al. — Investigation of mineral waters and soft drinks in relation to dental erosion (J Oral Rehabil 2001;28(8):766–772)
- Directive 2009/54/EC on the exploitation and marketing of natural mineral waters (EUR-Lex)
- NHS — Water, drinks and hydration
This article is for information only and does not replace advice from a doctor or dietitian. If you are unsure or have worrying symptoms, contact a doctor.