Is Diet Soda Unhealthy for People With Diabetes?

While sugar-free soda is almost certainly a better choice than most sugary drinks, studies suggest that it has some health downsides that make it a less healthy option than water. Diet soda can frustrate your weight loss efforts and diabetes management by increasing your appetite, and it may also increase the long-term risk of conditions such as kidney disease and heart disease.

Though it might be wise to ditch diet soda, experts differ on the magnitude and importance of its negative health effects.

With no calories, diet soda may be a better beverage choice for weight loss and weight maintenance than sweetened or naturally sugary drinks. But it seems to offer fewer weight loss and weight maintenance benefits than the ultimate healthy beverage: water.

The study included 81 women with type 2 diabetes who were overweight or had obesity and regularly drank diet sodas. All participants spent six months in a weight loss intervention program, followed by 12 months in a weight maintenance program.

To gauge the effect of drinking diet soda, researchers randomly assigned half of the participants to switch to water, while the other half stuck to their usual habit of having a diet soda after lunch five times a week.

After 18 months, the water drinkers lost more weight than the diet soda drinkers — 15 pounds on average, compared with 10.6 pounds — according to preliminary study findings presented at the 85th Scientific Sessions of the American Diabetes Association. The water drinkers were also about twice as likely to achieve diabetes remission.

One way diet sodas can help frustrate weight loss and diabetes management: They can trigger cravings for unhealthy foods.

There’s plenty of evidence that artificial sweeteners have other negative health effects, says Danielle Haslam, PhD, an instructor in medicine at Brigham and Women’s Hospital and Harvard Medical School and a nutrition researcher at the Harvard T.H. Chan School of Public Health in Boston.

More research is needed to better understand exactly how diet sodas impact health, particularly compared with water, Haslam says. While this work is ongoing, it makes sense to err on the side of caution and cut back on diet sodas and artificial sweeteners, she says.

However, not everyone agrees that this is an important switch to make. “I am of the opinion that the health risks of diet sodas are overstated,” says Robert Cohen, MD, a professor in the division of endocrinology, diabetes, and metabolism at the University of Cincinnati College of Medicine.

Though water might be the clear winner, that doesn’t necessarily mean diet soda is a truly unhealthy option, especially if it’s replacing sugared beverages in your diet.

The good news is that there are lots of alternatives to diet soda.

If you don’t like drinking lots of water, trying sparkling water instead of still is one way to get a fizzy drink without adding calories or artificial sweeteners to your diet, Cohen says.

There are plenty of other good alternatives too, says New York City–based Samantha Heller, RD.

“Water, tea, herbal teas, and seltzers are all good beverage options,” Heller says. She also suggests trying the following additions to zhuzh your water or seltzer:

• A small amount of pure fruit juice
• Fresh fruit slices like oranges, lemons, or strawberries
• Herbs like basil, mint, or rosemary
• Vegetables such as cucumbers

• Swapping diet soda for water as part of a weight loss program could lead to more pounds shed and a higher chance of type 2 diabetes remission.
• The artificial sweeteners in diet soda may increase a person’s appetite for calorie-dense foods, and they’ve also been linked to health risks like heart disease and cancer.
• Seltzer, tea, and diluted juice are all healthy substitutes for diet soda.
• Diet soda may have some negative health effects for people with diabetes, but the magnitude of those risks is unclear.

Additional reporting by Ross Wollen.