The Fizz Factor: Do carbonated drinks count towards water intake?

October 10, 2025 •

4 min read

According to a study co-authored by researchers at St. Andrews University, plain carbonated water hydrates the body just as effectively as still water. However, the simple question of whether do carbonated drinks count towards water intake has a more complex answer, as the additional ingredients drastically change the equation.

Quick Summary

Most carbonated beverages are primarily water and thus contribute to fluid needs, but factors like sugar, artificial sweeteners, and caffeine can affect overall health and counter hydration. The best option is unsweetened sparkling water or, preferably, plain water.

Key Points

Plain Sparkling Water is Hydrating: Unsweetened carbonated water provides the same hydration as still water, as confirmed by studies using the Beverage Hydration Index.
Sugar Counteracts Hydration: The high sugar content in regular sodas requires the body to use water for processing, potentially leaving you thirstier and undermining hydration.
Diet Sodas Have Side Effects: Despite being calorie-free, diet sodas contain artificial sweeteners linked to health issues and increased unhealthy food cravings.
Additives Damage Health: Many sodas contain phosphoric acid and caffeine, which can negatively affect bone density, kidney function, and dental health.
Still Water is the Optimal Choice: Water remains the best and most effective fluid for hydration without any added risks or empty calories.
Moderation is Crucial: If you must consume sugary or diet sodas, treat them as an occasional treat and not a daily source of hydration.

The Simple Answer: Yes, But It's Complicated

At its core, a carbonated drink is mostly water. In that sense, any liquid you consume, including soda, will contribute to your body's total fluid intake. However, this is not a recommendation to replace your daily water consumption with soda. The overall effect on your health and hydration depends entirely on the other ingredients present in the beverage. While plain carbonated water is a perfectly suitable alternative to still water, sugary and artificially sweetened options come with a host of ingredients that undermine their hydrating benefits.

Plain Carbonated Water vs. Still Water

When we talk about hydration and carbonation, a clear distinction must be made between plain sparkling water and other carbonated beverages. Plain sparkling water is simply water infused with carbon dioxide (CO2). Research has shown that plain sparkling water and regular still water are equally hydrating. The bubbles do not prevent your body from absorbing the water. In fact, for those who dislike the taste of flat water, the effervescence can encourage them to drink more, potentially improving overall hydration levels.

The benefits of plain carbonated water include:

Equivalent Hydration: Provides the same hydration as regular water.
Improved Digestion: Can help relieve indigestion and constipation for some individuals.
Sugar-Free Alternative: Offers a satisfying, fizzy option without the sugar and calories of soda.

However, some people may experience bloating or fullness from the carbonation, which could lead them to drink less. Additionally, during vigorous exercise, the carbonation can cause discomfort, making still water a better choice.

Sugary Sodas: The Hydration Myth

Sugary sodas, like regular colas, are more than just water with bubbles; they are liquid candy. While a 12-ounce can is about 93% water, it also contains nearly 9 teaspoons of added sugar. This high sugar content is detrimental to hydration. When you consume a high amount of sugar, your body pulls water from your cells to help process and dilute the sugar in your bloodstream. This effect can paradoxically leave you feeling even thirstier and contributes to dehydration over time. High sugar consumption is also linked to weight gain, diabetes, and other metabolic issues.

Diet Sodas: A Deceptive Alternative

For those looking for a calorie-free, carbonated option, diet sodas may seem like a healthier choice. However, they are not without their issues. Artificially sweetened beverages may still introduce health concerns. Studies have linked diet soda consumption to increased cravings for unhealthy foods and negative effects on gut health. Some research has even associated diet soda with risks like increased waist circumference, stroke, and heart disease in certain populations. While they provide fluid, they are not a nutritional substitute for water and come with their own set of potential health downsides.

The Hidden Dangers: Caffeine and Acidity

Beyond sugar and artificial sweeteners, many carbonated drinks contain other ingredients that can affect your body. Many colas contain caffeine, which is a mild diuretic. The amount of caffeine in soda is typically low and its diuretic effect is transient, meaning caffeinated beverages can still count toward fluid needs. However, relying heavily on them is less ideal for hydration than choosing plain water. Another significant concern, especially with dark colas, is the presence of phosphoric acid. This ingredient has been linked to:

Reduced Bone Density: It can hinder calcium absorption.
Kidney Issues: Regular consumption has been associated with increased risk of chronic kidney disease.
Dental Erosion: The combination of sugar and acid in soda is a major contributor to tooth decay and enamel erosion.

Comparison of Hydration and Health Factors

To better illustrate the differences, here is a comparison of various beverages regarding hydration and overall health.


Beverage	Hydration Effectiveness	Added Sugar	Calories	Primary Health Concerns	Best for Hydration?
Plain Water	Excellent	None	0	None	Yes
Plain Sparkling Water	Excellent	None	0	Potential bloating for some	Yes
Sugary Soda	Poor (due to sugar)	High	High	Weight gain, diabetes, dental erosion, kidney issues	No
Diet Soda	Moderate	None (artificial sweeteners)	0	Artificial sweeteners, gut health, increased cravings	No
Caffeinated Soda	Moderate (mild diuretic effect)	High or none	High or 0	Dehydration, caffeine side effects, dental erosion	No

Maximizing Hydration and Minimizing Risk

If you enjoy carbonated drinks but want to prioritize your health, consider the following strategy:

Choose Plain Sparkling Water: This is the best carbonated alternative to still water. Look for brands with no added sugar, sweeteners, or sodium.
Add Your Own Flavor: Infuse plain sparkling water with fresh fruits like lemon, lime, or berries for a refreshing and healthy flavor boost.
Prioritize Plain Water: Make plain water your primary source of hydration throughout the day.
Limit Sugary and Diet Sodas: Treat sugary and diet sodas as occasional indulgences rather than daily habits.
Drink in Moderation: As with any treat, moderation is key. A soda or two per week is less likely to have a significant negative impact than daily consumption.
Rinse Your Mouth: After drinking carbonated or acidic beverages, rinse your mouth with plain water to help wash away acids and protect your tooth enamel.

Conclusion: Making the Smartest Choice for Your Health

Ultimately, while technically carbonated drinks count towards water intake because of their liquid content, the quality of that hydration varies dramatically. Plain sparkling water is a healthy and effective hydrator, providing the same benefits as still water for those who enjoy the fizz. However, sugary and artificially sweetened sodas, especially those containing caffeine or phosphoric acid, introduce numerous health risks that can undermine hydration and overall wellness. For optimal health and hydration, water is the unequivocal best choice. When you want something with bubbles, opt for plain, unsweetened sparkling water.

For more information on the importance of plain water for health, consult the Centers for Disease Control and Prevention's guidance on healthy drinks.

Frequently Asked Questions

Yes, plain sparkling water is just as hydrating as regular water because its primary component is water. The carbonation does not interfere with your body's ability to absorb the fluid.

While diet sodas lack sugar, which can interfere with hydration, they still contain other additives like artificial sweeteners and caffeine. These ingredients are not as beneficial for hydration as plain water and come with their own set of potential health concerns.

Sugary sodas can contribute to dehydration due to their high sugar content, which draws water out of your cells during metabolism. Caffeinated sodas have a mild diuretic effect, which can also slightly increase fluid loss.

The acidity of carbonated drinks, particularly sodas, can contribute to the erosion of tooth enamel. The high sugar content in regular soda further increases the risk of tooth decay and cavities.

Yes, excessive consumption of sodas, especially dark-colored colas containing phosphoric acid, has been linked to an increased risk of kidney stones and chronic kidney disease.

If you struggle with plain water, try incorporating plain sparkling water or infusing still water with fruit slices like lemon, lime, or cucumber. Herbal teas can also be a hydrating option.

Most sodas have low levels of caffeine, and its diuretic effect is minimal. While caffeinated beverages can contribute to fluid intake, plain water remains the healthiest choice. Regular consumption of high-sugar or artificial sweetener-based drinks is not recommended.