Do fizzy drinks count towards hydration?

October 28, 2025 •

6 min read

According to the Centers for Disease Control and Prevention (CDC), nearly half of Americans drink at least one sugar-sweetened beverage a day, but can these beverages be counted toward your daily fluid goals? The question of, "do fizzy drinks count towards hydration?" is more complex than a simple yes or no, depending on the type of drink and its ingredients.

Quick Summary

The hydrating effect of fizzy drinks depends on their contents; while the water in them contributes to fluid intake, high sugar, caffeine, or artificial sweeteners can negate or complicate the benefits. Sparkling water hydrates similarly to still water, but sugary sodas and diet drinks introduce health risks like excess calories and metabolic issues, making plain water the superior choice for overall health.

Key Points

Not all fizzy drinks are equal: The hydrating properties of a fizzy drink depend heavily on its ingredients, not just the carbonation itself.
Plain sparkling water hydrates effectively: Unsweetened, unflavored sparkling water is just as hydrating as regular still water and can count towards your daily fluid intake.
Sugary sodas are counterproductive: Despite their water content, the high sugar and calorie load in regular fizzy drinks leads to health issues like obesity and diabetes, and the fluid provides little benefit.
Consider the impact of diet drinks: While calorie-free, diet sodas contain artificial sweeteners that may affect gut health and metabolism.
Water is the optimal choice: Plain water remains the best and most effective way to hydrate, offering zero calories and no additives.
Moderate caffeine content: Some fizzy drinks contain caffeine, which has a mild, short-term diuretic effect, but it's typically not strong enough to cause dehydration.
Enjoy fizzy drinks in moderation: For optimal health, sugary and diet fizzy drinks should be treated as occasional treats rather than a primary hydration source.

The Science of Hydration: Water vs. Fizzy Drinks

At its core, the human body needs water to function properly. Water is a core component of most beverages, including fizzy drinks. The misconception that carbonation itself is dehydrating has been debunked by scientific research. Studies, including one establishing a Beverage Hydration Index (BHI), have concluded that still and sparkling water are equally hydrating. The fizz from carbon dioxide does not inhibit the body's ability to absorb water.

The real issue arises not from the carbonation, but from the other ingredients common in many fizzy drinks. High amounts of sugar, artificial sweeteners, and caffeine can influence hydration and overall health in negative ways.

The Problem with Sugary Sodas

While a can of regular cola is mostly water, and thus technically provides some hydration, the sugar content effectively cancels out any benefit and introduces serious health concerns.

High Sugar Content: A single 12-ounce can of cola can contain nearly 40 grams of sugar, exceeding the daily recommended limit for both men and women. This can cause rapid spikes in blood sugar, followed by a crash, which affects energy levels and appetite.
Excess Calories: These sugary drinks contribute a significant amount of empty calories with no nutritional value, which is a major driver of weight gain and obesity.
Dental Health: The combination of high sugar and acidity in many soft drinks erodes tooth enamel and promotes cavities.
Systemic Health Risks: Regular consumption of sugary drinks is linked to an increased risk of type 2 diabetes, heart disease, fatty liver disease, and other metabolic issues.

The Pitfalls of Diet Fizzy Drinks

Diet sodas are often seen as a healthier alternative since they contain zero or very few calories. However, research suggests that their impact is not as benign as once thought.

Artificial Sweeteners: Artificial sweeteners like aspartame and sucralose have been linked to potential negative effects on gut microbiome and metabolic function.
Health Correlations: Studies have associated diet soda consumption with increased risk of metabolic syndrome, weight gain, and cardiovascular diseases, though the causal link is still under investigation.
Caffeine Content: Many diet fizzy drinks still contain caffeine. While the diuretic effect of caffeine is mild and transient, heavy consumption, especially in individuals with low tolerance, can still cause increased urination and counteract hydration efforts.

The Verdict on Sparkling Water

Plain, unsweetened sparkling water is essentially water with added carbon dioxide. For those who find plain still water unappealing, it can be an excellent way to increase daily fluid intake.

Equally Hydrating: Numerous studies confirm that carbonated water is just as hydrating as still water.
Additive-Free: As long as there are no added sugars, artificial sweeteners, or high sodium, it provides pure hydration without the negative health consequences of soda.
Encourages Consumption: For some, the pleasant fizz can make drinking more water throughout the day easier and more enjoyable.
Dental Acidity: While slightly more acidic than still water, its effect on tooth enamel is minimal compared to sugary and fruit-flavored fizzy drinks.

Comparison: Water vs. Fizzy Drinks

To illustrate the key differences, consider the following comparison table. This clarifies why water is the optimal hydration source and highlights the hidden costs of relying on fizzy drinks.


Feature	Water	Fizzy Drinks (Sugary Soda)	Sparkling Water (Plain)
Hydration Effectiveness	Excellent	Limited (negated by sugar/caffeine)	Excellent
Calorie Content	Zero	High (from added sugars)	Zero
Sugar Content	Zero	Very High (up to 40g per 12oz can)	Zero
Nutritional Value	None (unless mineral)	None (empty calories)	None (unless mineral)
Dental Impact	None	High risk of enamel erosion and decay	Minimal risk
Overall Health Impact	Supports vital bodily functions	Linked to obesity, diabetes, and heart disease	A healthy and safe alternative
Bloating/Discomfort	No	Can cause bloating from carbonation and sugar	Possible for some sensitive individuals
Ideal For	Daily primary fluid intake, exercise	Occasional treat	Daily fluid intake, healthy alternative

Making a Healthier Choice

For optimal health, water should be your primary source of hydration. However, for those who enjoy the sensation of a fizzy drink, unsweetened sparkling water is the clear winner. It provides the carbonated texture without the harmful additions of sugar and excessive caffeine. Here are some tips for navigating your beverage choices:

Transition from Soda to Seltzer: If you're used to sugary drinks, a good transition is to switch to plain or naturally flavored seltzer water. Adding a splash of fruit juice or a slice of citrus can provide flavor without large amounts of added sugar.
Choose Plain Options: Always check the labels for added sugars, artificial sweeteners, and sodium, especially in flavored sparkling waters. Opt for versions with minimal or no additives.
Moderate Consumption: While plain sparkling water is healthy, if you experience bloating or digestive discomfort, moderating your intake or alternating with still water is a good strategy. For athletes, still water is often preferable during exercise to avoid bloating.
Listen to Your Body: Pay attention to thirst signals and urine color. Pale yellow urine is a sign of good hydration, while darker shades indicate a need for more fluids.

Conclusion

In summary, while the water content in most fizzy drinks provides a measure of hydration, the added sugars, calories, and other ingredients can negate this benefit and pose significant health risks. Plain sparkling or mineral water, on the other hand, is just as hydrating as still water and offers a healthier, effervescent alternative for those who prefer it. Water remains the gold standard for maintaining optimal hydration and overall health. For fizzy drinks that are high in sugar, the best advice is moderation—they should be considered an occasional treat, not a primary hydration source. Choosing water or an unsweetened carbonated option is a simple but impactful choice for your well-being. For more in-depth nutritional guidance on this topic, consider consulting reliable sources like the Centers for Disease Control and Prevention [https://www.cdc.gov/nutrition/data-statistics/sugar-sweetened-beverages.html].

The Role of Sodium and Electrolytes

It's also worth noting that beverages containing electrolytes, particularly sodium, can sometimes enhance fluid retention and be more hydrating than plain water, as is the case with many sports drinks. However, sports drinks also contain sugar and should be used judiciously, mainly during periods of high-intensity, prolonged exercise where significant electrolytes are lost through sweat. For most people under normal circumstances, the mineral content in plain mineral water is sufficient, and the added sugars in sports drinks are unnecessary.

Summary of Key Differences

Understanding the nuanced differences between types of fizzy drinks is crucial for making informed choices. Plain carbonated water is largely benign and an effective hydrator, while sugary sodas are detrimental due to their high sugar and calorie load. Diet sodas fall into a grey area, with potential metabolic impacts from artificial sweeteners. The key takeaway is that the fizzy component itself is not the problem; it is the additional ingredients that determine the health implications of the drink.

Ultimately, when debating which beverage to choose for hydration, the simple purity of water—whether still or plain sparkling—will always be the healthiest, safest, and most effective option.

What happens if you stop drinking sugary fizzy drinks?

Quitting or significantly reducing your intake of sugary fizzy drinks can lead to several positive health outcomes, including weight management, improved blood sugar control, better dental health, and a decreased risk of chronic diseases like type 2 diabetes and heart disease. Replacing these beverages with water or unsweetened alternatives is one of the easiest ways to reduce your daily intake of added sugars and empty calories.

Are there any exceptions for athletes?

For endurance athletes who need to replenish energy and electrolytes, sports drinks (which are often fizzy) can serve a specific purpose during and after intense, long-duration exercise. However, for most everyday physical activity, plain water is all that is needed. The carbonation can cause bloating, which is uncomfortable during exercise, so many athletes prefer still fluids.

Frequently Asked Questions

Yes, multiple studies have shown that plain, unflavored sparkling water is just as effective at hydrating the body as still water. The carbonation from dissolved carbon dioxide does not inhibit water absorption.

Caffeine has a mild, transient diuretic effect that can increase urine output, but the amount of caffeine in most sodas is not enough to cause significant dehydration, especially if consumed in moderation. However, water is still a better choice for pure hydration.

While diet fizzy drinks don't have the high sugar content of regular soda, they are not necessarily a healthy hydration method. Artificial sweeteners can have their own negative health effects, and water or plain sparkling water is a healthier option.

The biggest health risk comes from the extremely high sugar and calorie content, which can contribute to weight gain, obesity, type 2 diabetes, heart disease, and significant dental problems like enamel erosion and cavities.

The carbon dioxide bubbles in fizzy drinks can cause bloating or a feeling of fullness for some people, especially if consumed quickly or in large quantities. This is particularly noticeable during physical activity.

For most everyday activity, plain water is sufficient. For high-intensity, long-duration exercise, some athletes may benefit from the electrolytes and carbohydrates in sports drinks. However, the carbonation can cause bloating, and still water is often preferred during exercise.

To boost hydration without plain water, you can try unsweetened sparkling water, adding slices of fresh fruit or a splash of citrus to water for flavor, or choosing other hydrating beverages like herbal tea or milk.