Are all carbonated drinks acidic? Unpacking the science of fizz and pH levels

December 17, 2025 •

2 min read

Most carbonated beverages have a pH below 7, which classifies them as acidic. The source of this acidity is a key chemical reaction that occurs during the carbonation process. So, are all carbonated drinks acidic, or are there exceptions? The answer is more nuanced than you might think.

Quick Summary

All carbonated drinks are acidic to some degree due to dissolved carbon dioxide forming carbonic acid. However, acidity varies greatly, with sweetened sodas being far more erosive than plain sparkling water.

Key Points

All are Acidic: Due to the carbonation process, which creates carbonic acid, all carbonated drinks have a pH below 7.
Acidity Varies Dramatically: The level of acidity is much higher in sugary sodas (pH ~2.5) than in plain sparkling water (pH ~5-6), which has only carbonic acid.
Sodas Contain Added Acids: Sweetened drinks often include phosphoric or citric acid for flavor and preservation, significantly increasing their acidity.
High Risk for Dental Erosion: The combination of sugar and high acidity in sodas is particularly damaging to tooth enamel, a non-regenerative tissue.
Mitigating Damage is Possible: Using a straw, rinsing with water, and drinking with meals can help reduce the acidic impact on your teeth.
Sparkling Water is a Healthier Alternative: For those craving fizz, plain sparkling water without added sugar or acids is a much safer option than soda.

The Science Behind the Fizz: Why Carbonation Creates Acidity

To understand whether all carbonated drinks are acidic, one must first grasp the science of carbonation. This process involves dissolving carbon dioxide (CO₂) gas under pressure into water, forming carbonic acid ($H_2CO_3$). This reaction is fundamental to all carbonated beverages, contributing to their acidic nature and the slightly tart sensation. The final acidity, or pH, is also affected by other ingredients.

The Role of Added Acids in Sodas

Sweetened carbonated drinks often contain additional, stronger acids like phosphoric or citric acid for flavor and preservation, significantly lowering the pH and increasing erosive potential. For example, colas can have a pH around 2.5, much more acidic than plain sparkling water.

pH Levels of Popular Carbonated Beverages

For information on the pH levels of popular carbonated beverages, including cola soda, citrus soda, energy drinks, sparkling water, and mineral water, and their primary acidic components, please refer to {Link: Reddit https://www.reddit.com/r/nutrition/comments/4knhe4/how_strong_is_the_acidity_in_carbonated_beverages/}. The acidity of carbonated beverages primarily impacts dental health and can affect individuals with sensitive digestive systems.

Dental Erosion: A Primary Concern

Acids can erode tooth enamel, which does not regenerate.

Digestive System Effects

While the body typically regulates pH effectively, carbonation can increase gastric pressure, potentially worsening symptoms for those with acid reflux or GERD.

Comparing Carbonated Drinks: Soda vs. Sparkling Water

Though both are acidic, sodas and sparkling water differ significantly in acidity and other ingredients.

Soda: Highly acidic due to added acids and carbonation; high sugar content increases dental risk and provides no nutritional value.
Sparkling Water: Mildly acidic due to carbonic acid only; generally free of sugar and artificial additives; less erosive to teeth; some mineral water may offer minerals.

Plain sparkling water is a healthier alternative for those seeking a fizzy drink without the significant health drawbacks of soda.

How to Reduce the Impact of Acidic Beverages

To help minimize the effects of acidic drinks, consider strategies such as drinking with meals, using a straw, or rinsing with plain water afterward. Waiting before brushing and choosing plain sparkling or mineral water can also be beneficial.

Conclusion: The Truth About Carbonated Drinks and Acidity

All carbonated drinks are acidic due to carbonic acid formed during carbonation. Acidity levels vary significantly, with sodas and energy drinks being much more acidic (pH ~2.5-3.5) than plain sparkling water (pH 5-6) due to added acids and sugar. This increased acidity makes sweetened beverages more damaging to dental health. For additional information, resources like Healthline are available.

Healthline - Carbonated (Sparkling) Water: Good or Bad?

Frequently Asked Questions

While slightly acidic due to carbonic acid, plain sparkling water is far less damaging to your teeth than sugary sodas or fruit juices. The risk is minimal, especially when compared to highly acidic beverages with added sugar and acids.

The pH level of most sodas, such as colas, ranges from approximately 2.5 to 3.5. This high level of acidity is primarily due to added acids like phosphoric and citric acid, in addition to the carbonic acid from carbonation.

Yes, the hydrochloric acid in your stomach (gastric acid) is much stronger than the acids found in carbonated drinks.

The prickly sensation is caused by the carbonic acid formed when carbon dioxide gas is dissolved in water. It stimulates the same nerve receptors in your mouth that are activated by mustard.

No, diet sodas are still highly acidic due to the same added acids (like phosphoric and citric acid) as regular sodas. While they lack the sugar, the acid content remains a significant threat to tooth enamel.

You can check the approximate acidity of a drink using a pH testing strip. For more precise measurements, especially during production, specialized sensors are used.

Some studies have linked soda consumption to lower bone mineral density, particularly in teenage girls, but evidence has suggested that non-soda carbonated beverages like sparkling water are not connected to this effect. Further research is needed.