Diet sodas contain sweeteners instead of sugar. While this may make them preferable to more sugary options, diet soda has links to weight gain and metabolic syndrome, which can worsen diabetes or increase the risk of developing type 2.

While it is not possible to prevent type 1 diabetes, a person may be able to reduce the risk of type 2 diabetes by maintaining a moderate weight.

However, any “no-sugar” drinks contain sugar substitutes that contribute to health problems and drive up body weight regardless of sugar content.

This article explores the effects of diet sodas on diabetes and how to replace them with less harmful options.

The absence of sugar or calories does not necessarily make diet soda a suitable drink for people with diabetes.

A 2018 study included 2,019 people who did not have diabetes at the start of the study. By the follow-up, 368 people had developed type 2 diabetes. The study found that there was a risk of type 2 diabetes among participants who consumed artificially sweetened sodas, as well as those who consumed sugar-sweetened sodas.

The study showed that participants with a higher body mass index (BMI) were at an increased risk of diabetes and more likely to be drinking diet soda. Even when using statistical methods to remove the influence of BMI, daily diet soda consumption was a significant predictor of developing diabetes among those participants who had overweight or obesity at baseline.

Another 2018 studyTrusted Source also found that consuming more than 4 cans of diet soda per week was associated with a more than twofold risk of proliferative diabetic retinopathy (PDR) in people with diabetes. PDR is an advanced diabetic eye disease that happens when new blood vessels grow in the retina.

Other factors that have come to light regarding the health risks of diet sodas include weight gain and metabolic syndrome.

Metabolic syndrome is a group of risk factors that often occur together. They increase the risk of type 2 diabetes, heart disease, and stroke.

These factors includeTrusted Source:

  • low levels of high-density lipoprotein (HDL), also known as “good” cholesterol
  • high levels of triglycerides, a type of fat in the blood
  • high blood sugar levels
  • larger waistline
  • high blood pressure

Older 2015 analysis suggests that people who drank at least one soft drink per day had a higher risk of metabolic syndrome compared with people who did not drink soda. This seemed to be particularly evident in consumers of diet soft drinks.

While these are observational results and do not prove a cause-and-effect relationship, diet soda is unlikely to be the best option for people looking to manage or prevent type 2 diabetes.

Obesity is a contributing factor in type 2 diabetes.

A 2015 studyTrusted Source looked at the long-term effects of diet soda on waist size, an indicator of visceral or belly fat.

This type of fat increases the risk of chronic disease more than fat in other areas of the body. The study lasted for 9.4 years and included a total of 749 participants over 65 years of age.

The waist circumference of participants increased when they drank diet soda for a long period. Participants who drank diet soda on a daily basis showed nearly quadruple the waist gain than those who did not drink it.

This shows a long-term link between consuming diet soda and developing belly fat. This, in turn, may increase a person’s risk of type 2 diabetes.

With the rise in the popularity of diet soda comes a matching increase in the use of alternative sweeteners.

People with diabetes sometimes view these sweeteners as viable alternatives to provide sweet flavoring, as they do not contain sugar.

The artificial sweeteners in diet sodas may still promote health risks, though many do not directly raise blood sugar. These risks include affecting the balance of healthy bacteria in the intestines, which may indirectly affect insulin sensitivity and appetite hormones.

The most common alternative sweeteners, whether artificial or natural, in diet sodas are:

  • Sucralose: A 2013 study showed this sweetener can raise blood sugar higher when carbohydrates are consumed later compared to those who did not consume any sucralose. Sucralose also causes peaks in insulin levels despite not containing sugar. The brand name is Splenda.
  • Aspartame: This is a chemical sweetener found in everything from diet soda to chewing gum. Aspartame can increase body weight and fat mass, which may increase the risk of diabetes.
  • Acesulfame Potassium (Ace-K): This is a sweetener commonly used in combination with other sweeteners in beverages and snack foods. Ace-K has been linked to body weight and fat gain in animal studies.
  • Sorbitol: This is a sugar alcohol that is common in diet foods and drinks. A 2022 study in mice found that long-term consumption of sorbitol altered the gut microbiome and induced glucose intolerance.
  • Stevia: A moderate amount of natural stevia leaf is generally a safe alternative to sugar for people with diabetes.
  • Erythritol: This is a corn-based type of sugar alcohol with fewer calories than table sugar but retains a majority of the sweet flavor. Consuming a moderate amount should not affect blood sugar or insulin levels. In fact, erythritol has shown protective effects for people with diabetes, though more research is necessary.

There are numerous alternatives that people might prefer to try instead of diet soda.

Carbonated water with a splash of fruit juice

People who drink soda for the refreshing fizz can choose carbonated water instead. Add a splash of fruit juice, such as lime, lemon, or grapefruit, for that sweet kick. The combination is rich in nutrients and rehydrates the body.

Unsweetened tea

Unsweetened black tea can be a tasty alternative for people who drink soda for the caffeine boost.

Iced, unsweetened black tea is also available and provides the same level of refreshment as a soda.

Some research suggests that drinking 3 to 4 cups of coffee per day may also help decrease the risk of type 2 diabetes.

Many low caffeine or noncaffeinated herbal teas such as citrus green tea, peppermint, and hibiscus are readily available.

Stevia leaves

People who crave the sweetness of soda might want to consider sweetening tea or carbonated water with whole stevia leaves. The leaves are a no-calorie sweetener with 200 to 400Trusted Source times the sweetness of sugar.

They have less of the appetite-enhancing effects of most artificial sweeteners.

If a person has diabetes, it is important to avoid drinks that contain excessive sugar, as they cause spikes in blood glucose.

A 2025 studyTrusted Source explains that soda and other sugar-sweetened beverages can also indirectly increase the risk of type 2 diabetes by contributing to weight gain.

Diet soda has links to weight gain and metabolic syndrome, which can worsen diabetes or increase the risk of developing type 2 diabetes.

Some sweeteners in diet soda even cause insulin spikes in the blood, which worsens insulin sensitivity over time and may eventually raise blood sugar levels.

To help curb soda cravings, a person can try adding a splash of fruit juice to carbonated water or drinking unsweetened tea.

People may wish to speak with a doctor if they have concerns about the risk of diabetes.