America, already a very fat nation, is also home to an impressive array of diet soda drinks, with just about every conceivable variety of fizzy sugar water available in low- or no-calorie form. While these drinks are ostensibly marketed towards the figure-conscious who seek to sate their sweet tooth without guzzling thousands of empty calories, it’s not working: Researchers from Johns Hopkins have discovered that consuming diet soda leads to increased calorie consumption from other sources.

What’s more surprising is that the study didn’t compare overweight diet soda drinkers to healthier folks who drank full-calorie beverages. In studies like that, correlation is the best possible result. Instead, the Hopkins team studied all overweight and obese people, some of whom consumed diet drinks, some full-calorie sodas.

In this case, those who preferred diet sodas still tended to have higher BIMs and consume more snack foods. The data come from The U.S. National Health and Nutrition Examination Survey (NHANES), which provided the raw statistics for the review, is designed as a nationally representative sample of about 5,000 persons each year, taken from across the U.S.

“Although overweight and obese adults who drink diet soda eat a comparable amount of total calories as heavier adults who drink sugary beverages, they consume significantly more calories from solid food at both meals and snacks,” said Sara Bleich, associate professor at the Johns Hopkins Bloomberg School of Public Health and lead author of the paper.

Scientists think that earlier research might reveal the cause of the phenomenon. In a normally functioning body, the sweetness receptors in the tongue help indicate to the brain how much energy is being consumed through “reward centers.” Artificial sweeteners (used by diet drinks to provide sweetness without the calories) are typically much, much sweeter than sugar, and thus register that much higher in the brain’s reward centers.

Over time, the consumption of ultra-sweet tasting diet soda may desensitize the tongue’s sweetness receptors. When the brain can no longer accurately interpret energy consumption, it’s easier to unconsciously consume extra calories from other foods.

The new Hopkins research contradicts findings from last year’s Harvard study, which suggested that diet soda consumption was unrelated to food cravings in obese people. That same study found links to depression and increased risk of heart disease, which continue to be validated as studies grow in scale.

If you must have a soda, do your body (and your taste buds) a favor and reach for the real thing.

“The results of our study suggest that overweight and obese adults looking to lose or maintain their weight—who have already made the switch from sugary to diet beverages—may need to look carefully at other components of their solid-food diet, particularly sweet snacks, to potentially identify areas for modification,” Bleich said.