Diet drink consumption may lead to weight gain and other negative health outcomes.

Q: Do diet drinks hinder the weight loss process and add to belly fat? If so, why? Can drinking one Diet Coke a day be bad for you if you’re trying to lose weight because of its artificial sweeteners? 

Diet drinks are advertised as a healthier alternative to their sugar- and calorie-laden counterparts, and they may be especially appealing to people wanting to lose weight.

However, years of research suggest that diet drinks aren’t the waistline-friendly choice that they’re made out to be. Diet drinks not only offer no nutritional value but also low or no-calorie artificially sweetened beverages like diet soda may harm your health in various ways.

For example, diet drink intake has been associated with an increased risk of developing chronic diseases, including metabolic syndrome, a cluster of symptoms that raises your risk of heart disease and diabetes. Specifically, diet beverage intake has been significantly linked to belly fat and high blood sugar, both of which are symptoms of metabolic syndrome (1, 2).

One study in 749 adults found that the waist circumference gain of people who consumed diet soda daily was nearly four times greater than non-consumers over a 10-year period. What’s more, artificially sweetened beverage consumption has been significantly associated with overweight and obesity (2, 3).

What’s more, diet drink intake may raise your risk of developing diseases like diabetes and harm your mental health (4, 5).

There are several ways in which diet drink consumption may lead to weight gain and other negative health outcomes. For example, the artificial sweeteners concentrated in diet beverages may lead to increased hunger and enhance cravings for higher calorie foods. Artificially sweetened drinks may also interfere with weight regulation mechanisms, disturb gut bacteria balance, and alter blood sugar regulation (3, 6).

Plus, people who regularly consume diet drinks are more likely to have poor diet quality and eat fewer fruits and vegetables than those who don’t drink them (3).

Although having a diet beverage once in a while is unlikely to significantly affect your health, it’s best to reduce your intake of artificially sweetened drinks as much as possible. If you’re used to having several diet drinks per day, slowly start replacing them with sparkling water, either plain or flavored with slices of lemon or lime. Giving up or greatly reducing your intake of diet drinks can be challenging, but it’s the best choice for your overall health.


Jillian Kubala is a Registered Dietitian based in Westhampton, NY. Jillian holds a master’s degree in nutrition from Stony Brook University School of Medicine as well as an undergraduate degree in nutrition science. Aside from writing for Healthline Nutrition, she runs a private practice based on the east end of Long Island, NY, where she helps her clients achieve optimal wellness through nutritional and lifestyle changes. Jillian practices what she preaches, spending her free time tending to her small farm that includes vegetable and flower gardens and a flock of chickens. Reach out to her through her website or on Instagram.