A new study is raising serious health concerns about diet sodas. Researchers say that drinking artificially sweetened beverages may be just as risky for your liver as regular sugary sodas.
The findings, presented at the United European Gastroenterology Week in Berlin, are based on more than a decade of data from over 120,000 participants. None of the individuals had liver disease when the study began. Scientists tracked their beverage habits and liver health for roughly 10 years.
People who drank sugar-sweetened beverages like soda, sweet tea or energy drinks had a 50 percent higher risk of developing metabolic dysfunction-associated steatotic liver disease, or MASLD. The condition was previously known as nonalcoholic fatty liver disease. It happens when fat builds up in the liver and can lead to inflammation, scarring and severe damage over time.
Those who drank diet drinks faced an even greater risk. Regular consumption of low- or non-sugar-sweetened beverages was associated with a 60 percent higher risk of developing the disease. Researchers also found that people who frequently consumed diet drinks were more likely to die from liver-related causes.
The study relied on detailed dietary information provided by participants over a median period of 10.3 years. Some individuals also underwent advanced imaging tests that confirmed increased fat accumulation in the liver. The greatest risks were seen among people who drank more than one can of either diet or regular soda a day.
Lead researcher Lihe Liu explained that while sugary drinks can spike blood sugar and insulin levels, diet sodas may interfere with the body in other ways. Artificial sweeteners can affect gut bacteria, alter feelings of fullness and increase cravings for sweets. Some evidence also suggests they may trigger insulin spikes similar to sugar.
Swapping one can of diet or sugary soda for water each day significantly lowered the risk of liver disease. Replacing diet soda with water reduced the risk by about 15 percent, while replacing sugary soda lowered it by about 13 percent. Simply switching from regular soda to diet soda offered no protection.
The researchers did not identify specific sweeteners used in the diet sodas, meaning different types may have different effects. They also cautioned that the study was observational. That means it shows a link but does not prove that drinking these beverages causes liver disease.
Liver disease is already one of the fastest growing health problems in the United States. According to the Centers for Disease Control and Prevention, more than 4.5 million American adults are affected.
Health experts say the safest option remains water. They note that choosing unsweetened beverages such as sparkling water or iced tea may help reduce risk.
The American Beverage Association and the study researchers have been contacted for comment.