Is Coke Zero Bad for You?

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 (1):

• Calories: 0
• Fat: 0 grams
• Protein: 0 grams
• Sugar: 0 grams
• Sodium: 2% of the Daily Value (DV)
• Potassium: 2% of the DV

To sweeten this beverage without adding calories, artificial sweeteners are used.

The health effects of artificial sweeteners are controversial, and concern regarding their safety is growing (2).

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 (3, 4, 5).

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 (1).

The only differences between Coke Zero and the new rebrand — Coca-Cola Zero Sugar — are minor changes to the natural flavor composition.

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Coke Zero does not contain any calories or sugar and is not a significant source of nutrients. It’s sweetened with artificial sweeteners, which have controversial health effects.

Research results on the effects of Coke Zero and other artificially sweetened beverages on weight loss are mixed.

One 8-year observational study found that people who drank more than 21 artificially sweetened beverages per week almost doubled their risk of overweight and obesity, compared with people who didn’t consume these kinds of drinks (6).

The same study noted that total daily calorie intake was lower in individuals who drank diet beverages despite their increase in weight. This suggests that artificial sweeteners may influence body weight in other ways than calorie intake (6, 7, 8).

Another study observed that drinking diet soda was associated with greater waist circumference over 9–10 years (9).

On the other hand, many human intervention studies indicate that the use of artificial sweeteners is either neutral or beneficial for weight management.

In one 6-month, randomized, controlled study, people with overweight or obesity experienced moderate weight loss of 2–2.5% of their body weight when replacing caloric beverages with diet beverages or water (10).

In another study, people in a 12-week weight loss program who drank artificially sweetened beverages lost 13 pounds (6 kg), while those drinking water lost 9 pounds (4 kg) (11).

Thus, the evidence on the effects of artificially sweetened beverages on weight management are conflicting, and more research is needed. However, we can put more trust in human trials than observational studies, which are more likely to be affected by other factors.

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The evidence on the use of Coke Zero and other artificially sweetened drinks for weight management is conflicting. More research is needed to understand the benefits and risks of diet beverages.

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 study on human teeth noted that phosphoric acid causes mild enamel and tooth erosion (12).

Another study 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 (13, 14).

Still, keep in mind that citric acid has been found to erode teeth more than phosphoric acid, which suggests that Coke Zero may affect tooth enamel slightly less than Diet Coke (12).

Additionally, Diet Coke had less erosive effects than other beverages, such as Sprite, orange juice, and apple juice (13).

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The acidic pH level of Coke Zero is associated with an increased risk of enamel and tooth erosion, though it may affect your teeth less than other acidic beverages.

Coke Zero is sugar-free. However, the sugar substitutes it contains may not necessarily be a healthier option for people looking to reduce their risk of diabetes.

A 14-year study in 66,118 women observed an association between drinking artificially sweetened beverages and an increased risk of type 2 diabetes (15).

Another study in 2,019 people showed a link between both sugar-sweetened drinks and artificially sweetened diet beverages and type 2 diabetes, suggesting that switching to diet soda may not lower your diabetes risk (16).

What’s more, in an 8-year study in 64,850 women, consuming artificially sweetened beverages increased the risk of diabetes by 21%, though the risk for those drinking sugar-sweetened beverages was even higher at 43% (17).

Interestingly, other studies have found opposing results.

A 14-year study in 1,685 middle-aged adults did not find any association between diet soda intake and an increased risk of prediabetes (18).

The results from these studies are conflicting and don’t provide an exact explanation of how artificially sweetened beverages increase your risk of diabetes. Therefore, more research is needed.

summary

Though Coke Zero is sugar-free, its artificial sweeteners are controversial. Still, research on the effects of artificial sweeteners on diabetes risk is mixed, and more studies are needed to fully understand a possible connection.

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 (19).
• Increased risk of kidney disease. The high phosphorus content in sodas may cause kidney damage. A study noted that those who drink more than 7 glasses of diet soda per week doubled their risk of kidney disease (20).
• Could alter your gut microbiome. Several studies indicate that artificially sweetened beverages can alter your gut microbiome, potentially causing poor blood sugar control (21, 22).
• May increase osteoporosis risk. One study observed that daily cola intake was associated with a lower bone mineral density of 3.7–5.4%. Similar results were found for those who drank diet cola beverages (23).

Further research is needed to determine the exact effects of Coke Zero and other diet beverages on your health.

summary

Coke Zero and other diet sodas are linked to alterations in the gut microbiome and an increased risk of osteoporosis and heart and kidney disease. However, more research is needed.

Coke Zero does not add nutritional value to your diet, and the long-term effects of drinking diet sodas are still unclear.

If you want to reduce your sugar or regular soda intake, opt for healthier, low-sugar drinks like herbal tea, fruit-infused water, and black coffee — and leave Coke Zero on the shelf.