Ask the Dietitian: Is Diet Soda Safe for Diabetes?

Diet soda doesn’t impact blood sugar levels like regular soda, but there are other health risks to consider.

If you live with diabetes, you’ve probably been advised to limit your intake of added sugar as much as possible, including your consumption of sugary drinks like soda.

Many healthcare providers recommend replacing regular soda with diet soda if you live with diabetes or prediabetes. The swap can help reduce your intake of carbohydrates and calories while improving blood sugar regulation.

While diet soda doesn’t have the same impact on blood sugar as regular soda, that doesn’t necessarily mean it’s a good choice for overall health.

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How does diet soda impact blood sugar compared to regular soda?

There are many types of artificial sweeteners used in diet soda, but aspartame is one of the most common. Aspartame is the artificial sweetener used in Diet Coke, one of the most popular diet sodas worldwide.

Aspartame is an artificial sweetener that provides the same amount of calories as table sugar, but it’s around 200 times sweeter. It’s commonly used in low calorie foods, chewing gum, and diet beverages like diet soda.

Because aspartame is so much sweeter than regular sugar, only a small amount is needed to make foods and drinks taste sweet. This helps reduce the number of calories in food and drinks and lessens their impact on blood sugar levels.

For example, a 12-ounce can of regular Coke contains 140 calories and 39 grams of added sugar, while the same serving of Diet Coke contains zero calories and zero added sugar.

Drinks high in added sugar, like regular soda, significantly impact blood sugar levels. Regularly consuming sugary beverages like soda are associated with an increased risk of developing diabetes, and can worsen glycemic control in people who already have diabetes.

Fiber and protein, which are found in balanced meals, help slow digestion and the absorption of sugar into your bloodstream. Because soda is high in sugar and low in protein and fiber, your body quickly absorbs the sugar into your bloodstream, causing your blood sugar levels to rapidly increase.

Zero-calorie, zero-sugar beverages like diet soda don’t impact blood sugar levels in the same way as regular soda.

Compared to the sweeteners in regular soda like cane sugar and corn syrup, artificial sweeteners like aspartame have a negligible effect on blood sugar levels. That’s why diet soda is sometimes recommended as a soda replacement if you live with diabetes.

While opting for diet soda over regular may help improve some aspects of blood sugar control, high consumption of diet soda may have a negative impact on glycemic control and other aspects of health in the long term.

Artificial sweeteners and diabetes

Some artificial sweeteners in diet soda may harm your health in several ways, especially when consumed in large amounts.

In the United States, aspartame is considered safe for human consumption by the FDA. However, the International Agency for Research on Cancer (IARC) classified aspartame as a Group 2B carcinogen, meaning it’s considered possibly carcinogenic to humans.

A 2022 study with 102,865 participants found that people who consumed large amounts of artificial sweeteners, especially aspartame and acesulfame-K (ace-K), had a 13% greater risk of developing cancer, specifically breast and obesity-related cancers.

However, cancer isn’t the only increased risk. Frequent consumption of diet soda and artificial sweeteners like aspartame, sucralose, and ace-K may negatively impact your microbiome, insulin sensitivity, and glycemic control.

Another 2020 study in people with type 2 diabetes found that the participants who consumed artificial sweeteners had higher insulin resistance compared to the participants who didn’t use artificial sweeteners. But study findings are conflicting and more high quality research is needed.

High intake of artificial sweeteners like aspartame has also been linked to an increased risk of heart disease, stroke, and brain-related conditions like depression and dementia.

Diet soda also has a high concentration of phosphoric acid, which can cause problems if you consume too much. Research suggests phosphoric acid in diet soda may increase your risk of bone fractures and osteoporosis.

While this doesn’t mean you have to completely avoid diet soda, it may be wise to limit your intake of artificially sweetened drinks and instead choose beverages that are safer or even beneficial for people with diabetes.

What to drink instead

Whether you have diabetes or not, it’s generally advised to hydrate with beverages that contain zero calories, such as water. But water isn’t your only option for maintaining your blood sugar levels.

Here are some other beverages to consider:

• Sparkling water: Sparkling water offers the carbonation of soda without the artificial sugar. If you’re craving diet soda or regular soda, try sipping sparking water with a splash of lemon juice instead.
• Green tea: Green tea offers a number of health benefits and may help reduce fasting blood sugar levels. Studies have shown that consuming green tea regularly may help enhance glycemic control and lower your risk of all-cause mortality if you live with T2D. Try opting for carbonated, unsweetened green tea on ice if you’re craving a bubbly drink.
• Hibiscus tea: Hibiscus tea has a tart taste and offers a number of health benefits due to its high concentration of anti-inflammatory and antioxidant compounds, including anthocyanins. According to research, hibiscus tea may help lower blood sugar, blood pressure, and blood lipid levels. If you don’t enjoy the taste of unsweetened hibiscus tea, you can use a natural, diabetes-friendly sweetener like monk fruit to counteract the tart taste.

Many beverages are healthier than diet soda, like unsweetened herbal teas, naturally-flavored sparkling and flat water, and other drinks sweetened with natural, zero-calorie sweeteners like monk fruit.

While it’s best to limit your intake of diet soda, you can still enjoy it from time to time. Your diet as a whole is what matters most when it comes to overall health and blood sugar control, so occasionally enjoying a diet soda won’t majorly impact your health.

Takeaway

Diet soda is calorie-free and doesn’t have the same impact on blood sugar as regular soda, which is why it’s commonly recommended to people with type 2 diabetes.

While swapping regular soda for diet soda may help improve short-term blood sugar control, research suggests that people who regularly consume diet soda and artificial sweeteners like aspartame have a greater chance of developing certain health conditions, such as heart disease, stroke, and certain cancers.

This doesn’t mean you have to give up diet soda for good, but it may be a wise choice to cut back on your diet soda intake and instead choose drinks known to support health and optimal blood sugar control, like lemon water and hibiscus tea.

Do you have a favorite beverage for maintaining your blood sugar levels? Share your tips with other Bezzy T2D members in the community forums.