Is Coke Zero Bad for You?

Health Line

21-05-2025

Coke Zero is calorie-free but has no nutritional value. While drinks with artificial sweeteners may have negative long-term effects, such as increasing the risk of type 2 diabetes, more research is needed.
Coke Zero, recently rebranded as Coca-Cola Zero Sugar, is marketed as a healthier version of the original sugar-sweetened beverage, Coca-Cola Classic.
It contains zero calories and sugar while providing the signature Coca-Cola flavor, appealing to those trying to reduce their sugar intake or control their weight.
This article takes a detailed look at Coke Zero and explains whether it's a healthy choice.

Zero nutritional value
Coke Zero does not provide any calories and is not a significant source of nutrition.
One 12-ounce (354-ml) can of Coca-Cola Zero Sugar (Coke Zero) offers:
Calories: 0
Fat: 0 grams
Protein: 0 grams
Sugar: 0 grams
Sodium: 2% of the Daily Value (DV)
Potassium: 2% of the DV
Artificial sweeteners are used to sweeten this beverage without adding calories.
The health effects of artificial sweeteners are controversial, and concerns regarding their safety are growing.
Though the research is inconsistent, some studies find that the use of artificial sweeteners may contribute to the development of obesity and metabolic syndrome, a cluster of conditions that increase disease risk.
Coca-Cola Zero Sugar (Coke Zero) uses several common artificial sweeteners, including aspartame and acesulfame potassium (Ace-K). The remaining ingredients are carbonated water, caramel color, food additives, and natural flavors.
The only differences between Coke Zero and the new rebrand Coca-Cola Zero Sugar are minor changes to the natural flavor composition.
Artificial sweeteners and weight loss
Research results on the effects of Coke Zero and other artificially sweetened beverages on weight loss are mixed.
In a 2023 52-week study of 493 adults, researchers found that compared to people who drank water, those who consumed beverages with non-nutritive sweeteners lost more weight over the study period, an average of 16.5 pounds (7.5 kilograms), compared to those who drank water, who lost an average of 13.4 pounds (6.1 kg).
However, a similar 2023 study that lasted 12 weeks found no difference in weight loss among participants who drank water versus beverages with non-nutritive sweeteners. The researchers also examined other metrics, like waist circumference, but found no significant differences. The non-nutritive sweetener group lost slightly more to their waist circumference, but the difference was about 1 centimeter (cm).
A 2023 review of research that looked at multiple studies suggests that non-nutritive sweeteners have no immediate effects on the metabolic or endocrine systems.
The evidence on the effects of artificially sweetened beverages on weight management is conflicting, and more research is needed. Long-term research is also needed to determine if artificial sweeteners may influence the body in ways other than calorie intake.
Diet sodas and tooth erosion
Similarly to regular soda, drinking diet sodas like Coke Zero is associated with an increased risk of tooth erosion.
One of the main ingredients in Coke Zero is phosphoric acid.
One 2002 study on human teeth noted phosphoric acid causes mild enamel and tooth erosion.
An older study from 2015 observed that Coca-Cola Light (Diet Coke), which differs from Coke Zero only in that it contains both phosphoric and citric acid, caused enamel and tooth erosion in freshly extracted cow's teeth in just 3 minutes.
Still, the same 2002 study suggests that citric acid erodes teeth more than phosphoric acid, which suggests that Coke Zero may affect tooth enamel slightly less than Diet Coke.
Diet Coke had less erosive effects than other beverages, such as Sprite, orange juice, and apple juice.
Coke Zero and diabetes risk
Coke Zero is sugar-free. However, the sugar substitutes it contains may not necessarily be a better option for people looking to reduce their risk of diabetes.
A large 2023 study involving 105,588 participants with a follow-up of 9.1 years suggests that consuming non-nutritive sweeteners is associated with an increased risk of developing type 2 diabetes.
A 2024 review of research suggests non-nutritive sweeteners may negatively affect the gut microbiome, or the helpful bacteria that live in your gut and aid digestion, potentially affecting metabolic health and contributing to diabetes risk and worse outcomes for people with diabetes.
The results from these studies don't provide an exact explanation of how artificially sweetened beverages increase your risk of diabetes. Therefore, more research is needed.
Other potential downsides
Artificially sweetened beverages like Coke Zero have been linked to other health issues, including:
Increased risk of heart disease: An observational study found a link between artificially sweetened beverages and an increased risk of heart disease among women with no prior history of heart disease.
Increased risk of kidney disease: Soda's high phosphorus content may damage kidneys. A 2017 study noted that those who drink more than 7 glasses of diet soda per week nearly double their risk of kidney disease.
Could alter your gut microbiome: Artificially sweetened beverages may alter your gut microbiome, potentially negatively affecting blood sugar management.
Further research is needed to determine the exact effects of Coke Zero and other diet beverages on your health.