What soft drink is keto? A Comprehensive Guide to Low-Carb Alternatives

November 7, 2025 •

4 min read

A single 12-ounce can of regular cola contains over 39 grams of carbohydrates, which is more than the typical daily carb limit for a ketogenic diet. For those managing this low-carb lifestyle, finding out what soft drink is keto-friendly is crucial to satisfying cravings without disrupting ketosis.

Quick Summary

The ketogenic diet requires careful beverage choices to stay within carb limits. While many popular diet and zero-sugar sodas are carb-free, they contain artificial sweeteners with potential side effects. Healthier options include sparkling water and naturally sweetened sodas.

Key Points

Diet Sodas are Technically Keto: Brands like Coke Zero and Diet Pepsi contain zero carbs, so they don't break ketosis.
Artificial Sweeteners are Controversial: Though carb-free, artificial sweeteners in diet sodas may increase cravings and are linked to other health concerns.
Sparkling Water is the Safest Option: Unsweetened, flavored sparkling waters like La Croix or Waterloo are zero-carb and contain no sweeteners, making them a worry-free choice.
Naturally Sweetened Sodas are Better: Brands like Zevia use natural, zero-carb sweeteners (stevia, monk fruit), offering a cleaner alternative to traditional diet sodas.
Homemade Sodas Provide Control: Combining sparkling water with fresh fruit juice and a keto-friendly sweetener allows for complete ingredient control.

Navigating Soda on a Keto Diet

When you're following a ketogenic diet, keeping your carbohydrate intake extremely low is essential to maintain ketosis, the metabolic state where your body burns fat for fuel. This makes traditional sugary soft drinks a definite no-go. A single serving of regular soda can instantly knock you out of ketosis, so many people turn to diet or zero-sugar versions. However, the decision isn't as simple as checking the carb count. The type of sweetener used and its potential effects on your health and cravings should also be considered.

The Controversial Role of Diet Soda

Popular diet sodas like Diet Coke, Coke Zero, and Diet Pepsi are technically keto-compliant because they contain zero carbs and zero calories. This is achieved by using artificial sweeteners such as aspartame, sucralose, and acesulfame potassium. From a purely mechanical standpoint, these sweeteners do not impact blood sugar and therefore do not directly interrupt ketosis. This makes them a widely accepted option for many keto followers looking for a quick and easy fizzy fix.

However, there is significant debate surrounding the long-term effects of artificial sweeteners. Some research suggests that they can contribute to increased sugar cravings, potentially leading to overeating and making it harder to stick with a low-carb plan. Concerns have also been raised about potential links between frequent consumption of artificial sweeteners and negative health outcomes, including metabolic issues and poor gut health. While diet soda won't kick you out of ketosis, it may be counterproductive to the overall health goals of a ketogenic diet.

Healthier Keto-Friendly Soft Drink Alternatives

Fortunately, for those who want to avoid artificial sweeteners or seek a cleaner option, there are several excellent keto-friendly soft drink alternatives. These alternatives can provide a satisfying bubbly experience without the controversial additives.

Flavored Sparkling Water: Brands like La Croix, Waterloo, and Bubly offer a wide variety of flavors in sparkling water with zero carbs, zero calories, and no artificial sweeteners. They are a great way to transition away from traditional soda while still enjoying some taste and carbonation.
Naturally Sweetened Sodas: Several brands now offer sodas sweetened with natural, zero-carb sweeteners like stevia, erythritol, or monk fruit. Brands such as Zevia and Virgil's Zero Sugar are popular choices for providing a more authentic soda taste without the sugar or artificial additives.
Homemade Keto Soda: You can easily create your own keto-friendly soft drink at home. Simply combine plain or flavored sparkling water with fresh citrus juice (lemon or lime) and your preferred keto-friendly sweetener (like stevia drops or monk fruit extract). This gives you complete control over the ingredients.
Kombucha: While some kombuchas can be high in sugar, certain varieties are low-carb and keto-friendly. Look for brands specifically marketed as low-sugar or check the nutrition label carefully. Kombucha also offers the added benefit of probiotics for gut health.

Comparison of Keto Soft Drink Options


Feature	Diet/Zero Sugar Soda	Naturally Sweetened Soda	Plain Sparkling Water	Homemade Keto Soda
Carbs	0g per serving	0g per serving (check label)	0g per serving	0g (if using keto sweetener)
Sweeteners	Artificial (Aspartame, Sucralose)	Natural (Stevia, Erythritol, Monk Fruit)	None	Keto-friendly sweetener of choice
Additives	Artificial flavors, colors	Natural flavors, sometimes fruit juice	None, or natural flavors	Fresh ingredients
Controversy	Potential metabolic disruption, cravings, gut issues	Some may experience GI issues with certain natural sweeteners	None	None
Taste	Often strong, lingering artificial aftertaste	Clean, less complex flavor	Subtle, natural flavor based on infused fruit	Fully customizable
Best For...	Occasional treat for those with no sensitivity	Regular consumption with minimal health concerns	Quenching thirst and hydration	Maximum control over ingredients

Making the Best Choice for Your Keto Journey

Ultimately, deciding what soft drink is keto-appropriate for you depends on your individual health goals and how your body responds to different sweeteners. For strict adherence to the diet's health principles, prioritizing hydration with plain water and unsweetened sparkling water is the best course of action. These options pose no risk to ketosis and help you stay properly hydrated, which is especially important during the initial stages of a keto diet.

If you find yourself craving a sweeter taste, naturally sweetened sodas or homemade versions offer a compromise without the potential drawbacks of artificial sweeteners. Pay close attention to how these affect you, as some natural sugar alternatives can still cause digestive issues for certain people.

The key is moderation and informed choices. While diet sodas are technically carb-free and won't kick you out of ketosis, their long-term health implications and potential for increasing cravings make them less than ideal for many people. By exploring the range of healthier alternatives, you can enjoy a refreshing soft drink experience that aligns better with the overall health and wellness objectives of the ketogenic diet.

Conclusion

While many diet and zero-sugar soft drinks are technically carb-free and won't directly break ketosis, they are not the healthiest choice for a ketogenic lifestyle. Their reliance on artificial sweeteners can create metabolic confusion and increase cravings, which are counterproductive to long-term success. The best and most straightforward keto-friendly soft drink is unsweetened sparkling water, optionally flavored with fresh citrus. Other excellent choices include naturally sweetened sodas like Zevia and homemade versions with keto-approved sweeteners. By choosing wisely, you can enjoy a bubbly beverage without compromising your progress or health. For more general information on healthy low-carb choices, you can explore resources like Healthline's keto guides.

Frequently Asked Questions

No, diet soda itself will not kick you out of ketosis because it contains zero carbohydrates and does not raise blood sugar. However, some experts suggest that the artificial sweeteners may still cause an insulin response in some people, potentially hindering progress.

The best sugar-free sodas for keto are those sweetened with natural, plant-based sweeteners like stevia, erythritol, or monk fruit. Brands like Zevia and Olipop are good examples that offer a sweet flavor profile without relying on controversial artificial additives.

Regular tonic water is not keto-friendly as it is high in sugar and carbs, similar to conventional soda. You must use a diet or slimline tonic water, which is sweetened with artificial sweeteners and has zero carbs, if you wish to use it as a mixer.

Yes, homemade keto sodas are very simple to make. You can combine carbonated water with fresh fruit extracts or juice from keto-approved fruits (like lemon or lime) and a few drops of your preferred keto-friendly liquid sweetener.

Some people on a ketogenic diet choose to avoid diet soda because it contains artificial sweeteners that can potentially increase sugar cravings, affect gut health, or cause metabolic dysregulation over time, which goes against the clean-eating spirit of the diet.

The best way to find a keto-friendly soft drink brand is to check the nutrition label for carbohydrates and ingredients. Look for zero-carb and zero-sugar options, and prioritize brands that use natural sweeteners like stevia or monk fruit if you want to avoid artificial additives.

For most popular sparkling water brands like La Croix or Waterloo, the natural flavors are carb-free. However, always double-check the label, as some varieties may be naturally sweetened with fruit juice, which can add a small amount of carbs.