How Many Zero Sugar Drinks Can You Have a Day?

October 10, 2025 •

4 min read

According to the U.S. Food and Drug Administration (FDA), artificial sweeteners found in zero-sugar drinks are considered safe when consumed in moderation. While this official stance provides a framework, the question of how many zero sugar drinks can you have a day remains a complex issue with ongoing debate among experts.

Quick Summary

This article delves into the acceptable daily intake guidelines for sweeteners in zero-sugar beverages, examines the potential health effects of regular consumption, and recommends healthier alternatives.

Key Points

FDA's ADI is a High Limit: The Acceptable Daily Intake (ADI) set by the FDA is a very high amount based on lifetime safety studies, not a recommended daily target.
Individual Factors Matter: The safe amount of zero-sugar drinks depends on individual body weight, metabolism, and sensitivity to specific artificial sweeteners.
Potential for Weight Gain: Despite zero calories, some research suggests artificial sweeteners can alter brain chemistry and increase cravings for high-calorie foods, potentially leading to weight gain.
Concerns Beyond Weight: Regular consumption has been linked to metabolic syndrome, altered gut microbiome, and dental erosion due to the drinks' acidity.
Water is Best: The most health-conscious approach is to prioritize water and other unsweetened alternatives, treating zero-sugar drinks as an occasional indulgence.
Consider the Sweetener: Different artificial sweeteners, like aspartame or sucralose, are metabolized differently, and potential health concerns may vary by type.

The Acceptable Daily Intake (ADI) and How It's Calculated

For many, zero-sugar drinks seem like the perfect solution for satisfying a sweet tooth without the calorie and sugar content of regular sodas. The key to understanding safe consumption lies in the Acceptable Daily Intake (ADI), a metric established by health organizations like the FDA and the World Health Organization (WHO). The ADI represents the maximum amount of a substance that is considered safe for a person to consume each day over a lifetime without adverse health effects.

However, this number is not a one-size-fits-all metric. The ADI is calculated per kilogram of body weight, so a 150-pound individual's safe intake will differ from a 200-pound person's. Furthermore, the specific ADI varies depending on the type of artificial sweetener used. For example, the ADI for aspartame is 50 mg per kilogram of body weight. A single 12-ounce can of diet soda contains roughly 200 mg of aspartame, meaning a 150-pound (68 kg) person could theoretically drink around 17 cans per day without exceeding this limit. This number seems high, and is based on studies that found no adverse effects at 100 times the ADI in animal studies, providing a large safety margin. Yet, health experts advise that this theoretical maximum should not be confused with a healthy daily target.

The Mixed Evidence and Emerging Health Concerns

Beyond the official ADI, the long-term health implications of frequent zero-sugar drink consumption are still under investigation, with conflicting results in the scientific community. Some observational studies suggest a link between habitual diet soda consumption and an increased risk of health issues, including metabolic syndrome, type 2 diabetes, and cardiovascular disease. These studies show correlation, not causation, and other factors like lifestyle choices can play a role. For instance, a 2023 study found an association between consuming non-nutritive sweeteners and a higher risk of metabolic dysfunction-associated steatotic liver disease (MASLD), challenging the perception that these drinks are harmless.

Potential Negative Health Effects

Weight Gain: Despite being calorie-free, some studies suggest that artificial sweeteners can alter the brain's reward response to sweetness, potentially leading to increased cravings for high-calorie foods and, over time, weight gain.
Insulin Confusion: The brain and body typically associate a sweet taste with a caloric intake. Consuming artificial sweeteners can disrupt this connection, with some research indicating it may lead to insulin spikes even without sugar.
Gut Microbiome Disruption: A growing body of research points to the potential of artificial sweeteners to negatively impact the balance of beneficial bacteria in the gut, which can affect metabolic health and digestion.
Dental Erosion: Many zero-sugar sodas contain acidic ingredients like phosphoric and citric acid. While they don't cause cavities like sugar, this acidity can erode tooth enamel over time.

Comparison of Common Zero-Sugar Beverages and Water

To make an informed decision, it's helpful to compare zero-sugar drinks with the gold standard for hydration: water. The following table contrasts a typical zero-sugar soda with plain water across several key health metrics. Note: This is a generalized comparison, and nutritional content can vary by brand and product type.


Feature	Zero-Sugar Soda	Plain Water
Calories	0	0
Nutritional Value	None	Contains trace minerals, essential for hydration
Artificial Sweeteners	Yes (e.g., Aspartame, Sucralose)	No
Potential Gut Impact	Possible disruption of gut microbiome	Supports healthy gut function and digestion
Tooth Enamel Impact	Acidity can cause enamel erosion	Supports oral health and prevents dental issues
Weight Management	Inconclusive; potential to increase cravings	Zero-calorie, promotes feelings of fullness, ideal for weight management
Hydration	Yes, but caffeine can have a diuretic effect	The gold standard for optimal hydration

Healthier Alternatives to Zero-Sugar Drinks

Rather than fixating on the number of zero-sugar drinks one can have, many health experts recommend shifting towards genuinely healthier beverage options. Making this change can help you appreciate the natural sweetness of whole foods and reduce your body's reliance on artificial sweeteners.

Infused Water: Add slices of lemon, cucumber, berries, or fresh mint to plain water for a refreshing and hydrating twist without any artificial additives.
Seltzer Water: For those who crave carbonation, seltzer or sparkling water is a great calorie-free alternative. Some brands offer naturally flavored options with no sweeteners.
Unsweetened Herbal Tea: Teas like peppermint, chamomile, or hibiscus offer a variety of flavors and can be enjoyed hot or cold without any sugar.
Black Coffee or Tea (Unsweetened): For a caffeine boost, unsweetened coffee or tea is a better choice than artificially sweetened diet versions, provided caffeine intake is monitored.
Water with a Splash of Fruit Juice: For a touch of sweetness, a small amount of 100% natural fruit juice can be added to water. The NHS recommends limiting fruit juice to no more than 150ml per day to control sugar intake.

Conclusion

There is no single magic number for how many zero sugar drinks you can have in a day. While regulatory bodies establish a high Acceptable Daily Intake for artificial sweeteners, this does not mean unlimited consumption is advisable. A wide range of observational studies and emerging research have raised concerns about the long-term health effects of excessive intake, from potential weight gain and metabolic disruption to dental and gut health issues. Instead of replacing one habit with another, the healthiest approach is to prioritize water and other naturally unsweetened beverages. Zero-sugar drinks are best viewed as an occasional treat rather than a daily staple, helping your body recalibrate its appreciation for natural flavors and reducing exposure to artificial ingredients.

Authority Link

For more information on the Acceptable Daily Intake (ADI) and the regulation of artificial sweeteners, refer to the U.S. Food and Drug Administration's official guidance: https://www.fda.gov/food/food-additives-petitions/aspartame-and-other-sweeteners-food.

Frequently Asked Questions

While most health organizations consider moderate consumption of zero-sugar drinks safe, observational studies have linked even a single can a day to increased risks for issues like type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (MASLD). It is best to treat it as an occasional treat rather than a daily habit.

Yes, some studies indicate that artificial sweeteners in zero-sugar drinks can alter the gut microbiome, potentially disrupting the balance of beneficial bacteria. This can lead to digestive issues and may have broader metabolic impacts.

Despite having zero calories, some research suggests they can contribute to weight gain. Artificial sweeteners may affect appetite and cravings for sweeter, higher-calorie foods, leading to overeating.

Yes, they can be harmful to dental health. The phosphoric and citric acids found in many diet sodas can erode tooth enamel over time, increasing the risk of cavities and sensitivity.

Healthier alternatives include water, seltzer or sparkling water, unsweetened herbal tea, and water infused with natural fruits like lemon or cucumber. These options hydrate you without exposing your body to artificial sweeteners or acids.

While zero-sugar drinks do not contain sugar, some research shows that certain artificial sweeteners like sucralose can cause insulin and blood glucose spikes, potentially contributing to insulin resistance over time. The long-term effects on blood sugar control are still being researched.

Yes. Individuals with phenylketonuria (PKU), a rare genetic disorder, must avoid aspartame. People with sulfonamide allergies should also avoid saccharin. Additionally, pregnant women should consult their healthcare provider regarding consumption.