The study divided primary tooth enamel samples into five groups: Coca-Cola Classic (sucrose), Diet Coke (aspartame), Zevia Cola (erythritol), Coca-Cola Life (stevia), and a saline control. Each specimen was exposed to the beverage for a total of sixty minutes. The authors report: "All tested sodas resulted to a statistically significant change on the surface roughness of the enamel (p = .000). However, this effect did not differ significantly between the different treatment groups (p = .103)." They conclude: "Both regular soda and low calorie soda containing different commercial sweeteners appear to have an effect on the surface morphology of primary tooth enamel. Thus, it is important to discourage the intake of any type of soda."

This experimental study compared enamel erosion from a regular Coca-Cola beverage and a diet Coca-Cola beverage at different temperatures using extracted human premolars. The authors state: "The findings of the present study showed that both studied beverages can potentially erode the enamel surfaces after immersion cycles." They further report that the regular beverage did not show significant difference compared with control, "but the diet type showed a considerable significant difference in terms of enamel softening." In the conclusion they write: "Diet Coca-Cola is more erosive than the regular type and the temperature of the beverages used had no significant influence on enamel erosion."

A narrative review on soft drinks and oral health notes that soft drinks containing inherent acids and sugars have both acidogenic and cariogenic potential. It states: "Soft drinks containing inherent acids and sugars have both acidogenic and cariogenic potential, resulting in dental caries and potential enamel erosion." The paper highlights that low-calorie drinks do not necessarily avoid erosion: "To reduce dental caries risk, the low-calorie and sugar-free food was recommended. However, sugar-free soft drinks often have as high erosive potential as sugar-containing soft drinks." The authors conclude that excessive intake of soft drinks can cause dental erosion and caries.

This systematic review examines dental erosion associated with carbonated soft drinks in general rather than sugar content per se. It concludes that "an abuse of carbonated acid substances leads to an increase in the possibility of dental erosion with consequent structural disintegration and reduction" of enamel. The authors emphasize that most commercial carbonated drinks are acidic enough to demineralize enamel and that frequency and duration of exposure are key determinants of damage, regardless of whether the drinks are sugar-sweetened or not.

NIDCR explains that tooth decay occurs when bacteria in the mouth use sugars in foods and drinks to produce acids that attack tooth enamel. It notes that frequent sipping of sugary drinks, including soft drinks, increases the length of time that acids remain on teeth and can accelerate decay. While this page focuses on sugar’s role in caries, it separately notes that acidic beverages also can contribute to enamel erosion, which is a distinct process from decay but can weaken teeth and make them more susceptible to damage.

This state public health guidance explains that soft drink consumption is a leading cause of tooth decay and that carbonation, sugar, and acids weaken enamel. It emphasizes that sugar-free sodas still pose a risk: "Soft drink consumption is one of several leading causes of tooth decay. Carbonation, sugar and acids in soft drinks weaken tooth enamel and encourage the growth of bacteria that contribute to tooth decay." The page warns: "Remember, diet or 'sugar-free' soda still has acid that can harm your teeth." A table on beverage pH lists Diet Coke with a pH of 3.6 and 0 grams of sugar, illustrating its acidity despite being sugar-free.

Summarizing research from Melbourne University's Oral Health Cooperative Research Center, the article reports that while sugar-filled sodas, sports drinks, and juices are known to be bad for teeth, "their **sugar-free counterparts aren't great for your teeth either**." A dentist explains that in sugar-free drinks, "phosphorous and citric acid can wear away the enamel of teeth." The piece notes that "while sugar-free drinks will not lead directly to cavities, the weakening of enamel can cause a host of problems" such as sensitivity, staining and chipping.

In this in vitro study, Rodgers and von Fraunhofer compared enamel dissolution from both regular and diet soft drinks. The paper notes that soft drinks "tend to be carbonated, have a low pH, and contain sugar and a variety of other additives, [and] may subject dental enamel to acid dissolution and/or erosion." Their data show that enamel dissolution from cola drinks was 55–65 times greater than from water and root beer and that "no differences in enamel dissolution were found between regular" and diet versions of the tested soft drinks, indicating similar erosive effects on enamel irrespective of sugar content.

In an interview-based article, a dentistry professor states that many scientific studies have shown a relationship between soda consumption and enamel erosion. Regarding diet versus regular soda, she says: "You may be saving calories by drinking diet soda, but when it comes to enamel erosion of your teeth, it’s no better than regular soda." The piece explains that phosphoric and citric acid in many popular sodas and diet sodas alter the pH in the mouth and can cause tooth erosion over time, and advises limiting soda intake regardless of sugar content.

Penn Dental Medicine explains that soda is bad for teeth mainly because of "sugar and acid." It notes that patients often ask whether diet or sugar‑free colas are safer, and responds that these sodas "may have fewer added sugars, but, **like all sodas, they are highly acidic**." It highlights that sodas commonly contain citric and phosphoric acid and that carbonation forms carbonic acid, all of which "can erode enamel over time, leaving teeth vulnerable to sensitivity, decay, and even tooth loss."

This review of carbonated beverages and tooth structure states that "overindulgence in acidic carbonated beverages raises the possibility of dental erosion, which results in enamel deterioration and loss of its mechanical and physical qualities." It notes that "most commercial carbonated drinks have a pH lower than what is necessary for the demineralization of enamel" and that the length of exposure and the acidity of beverages have differing negative effects on enamel. The authors highlight that rougher enamel surfaces from erosion encourage more bacterial adherence and a higher possibility of cavities, reinforcing that acidity, not sugar content alone, drives erosion.

This dental practice notes that while sugar-free drinks have fewer calories than regular sugary drinks, "they can still cause some harm" to health and dental health. It explains that diet soda and other artificially sweetened beverages "contain acids that cause tooth decay" and that "the acids can wear away the enamel on your teeth." Over time, this weakened enamel "can lead to cavities or other dental problems." The article concludes that sugar-free soft drinks can be an occasional treat but should not replace water as the main beverage.

This oral health guidance notes that while sugar-free drinks avoid the direct cariogenic effect of sugar, their acidity can still damage enamel. It states: "Unfortunately, although they often contain no sugar, diet sodas usually cause about the same amount of dental erosion as regular sodas and can harm your teeth." The explanation attributes this to acids like phosphoric and citric acid and low pH that can erode enamel, recommending water and milk instead of either regular or diet soda for better dental health.

The pediatric dental site explains that while sugars can cause a lot of damage, "they are not the only concern for the mouth." It says that when you eliminate the sugar with a diet soda, "you are only eliminating the sugars" and that "much like the carbonated water, **the acids can create damage on the teeth and wear down enamel over time**." It also notes that while sugar-free drinks may lessen the chance of cavities, some drinks can increase the chances for stained teeth.

This dental practice article summarizes experimental findings on enamel loss from regular and diet sodas. It cites work by University of Michigan researchers Rodgers and von Fraunhofer, noting that after 14 days of exposure "regular soda had dissolved 3.0 mg/cm² of enamel while diet soda had dissolved 2.8 mg/cm²." The article concludes that diet soda "poses only marginally less of a threat than its sugar-laden counterpart" and that both diet and regular soda have acidity levels close to stomach acid, which can corrode enamel through dental erosion regardless of sugar content.

This dental practice notes that while zero-sugar sodas do not contain the sugar that contributes to tooth decay, "they still pose a few risks to dental health." It explains that the acidity of these beverages "can erode tooth enamel over time" leading to sensitivity, discoloration, and increased susceptibility to cavities. The article adds that "some studies suggest that the **acidic pH of zero-sugar sodas may contribute to enamel erosion even more than sugary sodas**" and cites research indicating that people who consumed diet soda every day were three times more likely to experience dental erosion than non‑drinkers.

The dental office writes that very sugary sodas damage teeth because sugar attracts bacteria that decay enamel and lead to cavities. It then explains that diet sodas, although low or no sugar, "may not contain sugar, but they do contain acids that can cause just as much enamel erosion as regular sodas." It warns to beware of ingredients like phosphoric, citric, and tartaric acids, which bond with calcium, weaken teeth, and leave enamel thin and sensitive, showing that both regular and diet sodas are harmful for oral health.

This dental clinic article explains that "the main culprit in these drinks that leads to decay is the acid content" and that "diet sodas and other sugar-free drinks are usually highly acidic, which weakens the enamel on your teeth and makes them more susceptible to cavities and dental erosion." It notes that regular sodas add sugar, which feeds decay-causing bacteria, creating a "double-whammy" of sugar and acidity, while diet sodas remove the sugar but typically still contain high levels of phosphoric, citric, or tartaric acid that can erode enamel.

This endodontic practice notes that "you may be saving calories by drinking diet soda, but when it comes to enamel erosion of your teeth, it's no better than regular soda." The article explains that phosphoric and citric acids, common in many sodas and diet sodas, alter pH in the mouth and can cause tooth erosion over time. It stresses that soda "in any form is detrimental to your oral health" and that enamel erosion can cause tooth sensitivity that cannot be reversed by dental treatment.

This dental practice article states that "numerous studies show that the high acid content of all sodas causes tooth erosion at roughly the same rate, regardless of sugar content." It explains that regular sodas are a "double whammy" because they supply both acid and sugar (for bacteria), whereas diet sodas usually contain "the exact same acid as regular soda (phosphoric acid) plus additional acids (citric acid, tartaric acid)." The article cites a University of Melbourne study testing 15 sodas and finding that all 15, whether sugared or artificially sweetened, "caused about the same amount of tooth erosion in the same amount of time."

This orthodontic blog explains that in diet sodas and other sugar-free drinks "the main culprit ... that leads to decay is the acid content." It notes that these drinks are usually highly acidic, which weakens enamel and makes it more susceptible to cavities and erosion. In contrast, regular soda is high in sugar, and a 12-ounce can has roughly ten teaspoons of sugar that feed decay-causing bacteria, so regular sodas deliver both sugar and acidity. The article recommends avoiding both types and provides tips to lessen tooth decay if they are consumed.

Summarizing several in vitro studies on sodas and enamel, the article notes that both sugared and diet soft drinks can cause substantial enamel loss in extracted teeth. It describes a Southern Illinois University study comparing multiple sodas and their diet counterparts: "The results: teeth soaked in Coke, Pepsi, RC Cola, Squirt, Surge, 7-Up and Diet 7-Up lost more than 5 percent of their weight. The remaining sodas (their complementary diet versions, except Diet 7-Up) caused enamel losses ranging from 1.6 percent to 5 percent." It highlights that "Diet 7-Up eroded more than 5% of enamel" and explains that, despite lacking sugar, its carbonation and citric acid content eroded enamel. The article concludes that diet sodas are also erosive and that acidity and acids like citric acid are key drivers of enamel loss.

This 2026 blog discusses whether diet soda is better for teeth than full-sugar soda. It explains that the sugar in regular soda feeds bacteria that produce acids responsible for cavities and enamel damage. For diet soda, it states that "the acidity in diet soda can erode enamel, leading to sensitivity and an increased risk of decay." The article concludes that both types of soda pose significant risks to oral health and that minimizing consumption is the best approach.

This dental practice article explains that diet sodas, including Diet Coke, can harm teeth due to their acidity. It states: "Diet sodas, including Diet Coke, contain phosphoric and citric acid, which can erode tooth enamel over time. While they may be sugar-free, the acidity in these beverages still poses a significant risk to your dental health." It notes that Diet Coke has a low pH level and that the carbonation and added acids "can gradually wear down your enamel," recommending strategies such as limiting frequency, using a straw, and rinsing with water after drinking.

From a mechanistic standpoint, sugar-sweetened soft drinks damage teeth in two main ways: (1) fermentable sugars feed oral bacteria, producing acid that causes dental caries (cavities), and (2) the drinks themselves are acidic, contributing to enamel erosion. In contrast, sugar-free soft drinks do not provide fermentable sugars, so their direct cariogenic (cavity-causing) potential is lower, but they often contain similar levels of acids (e.g., phosphoric or citric acid) and have low pH. As a result, sugar-free sodas can cause enamel erosion comparable to sugared sodas, while typically causing fewer caries if other sugar sources are controlled.