A new UK study has revealed that consuming just one can a day of fizzy drinks, whether sugary or ‘diet’, significantly raises the risk of developing liver disease. The research highlighted that both types of beverages may contribute to fat accumulation in the liver and, in some cases, increase the likelihood of liver-related deaths.

The study, presented during the European Gastroenterology Conference (UEG) Week 2025, followed 123,788 adults who had no signs of liver disease at the start of the research for about 10 years. Participants’ drink habits were recorded using repeated 24-hour dietary questionnaires, allowing scientists to examine the relationship between sugar-sweetened beverages (SSBs), low- or no-sugar sweetened beverages (LNSSBs), and metabolic dysfunction-associated steatotic liver disease (MASLD).

The researchers found that individuals who consumed more than 250 grams, about one can of either beverage daily, faced substantially higher risks. Those drinking LNSSBs had a 60 per cent higher chance of developing MASLD, while regular SSB consumers had a 50 per cent increased risk. Over a median follow-up of 10.3 years, 1,178 participants developed MASLD and 108 died from liver-related causes. While SSBs were not strongly linked to liver-related deaths, “diet” drinks were associated with increased mortality. Both drink types were also connected to higher liver fat levels.

MASLD, previously called non-alcoholic fatty liver disease (NAFLD), occurs when excess fat builds up in the liver, potentially causing inflammation, abdominal pain, fatigue, and loss of appetite. It is now the most common chronic liver condition globally..affecting more than 30 per cent of people and increasingly contributing to liver-related deaths.

Lead researcher, Lihe Liu, explained that while sugary drinks have long been scrutinised, “diet” alternatives are often perceived as healthier. He noted, however, that both are widely consumed, and their effects on liver health were not fully understood. “Our study shows that low- or no-sugar drinks were linked to a higher risk of MASLD even at modest intake levels, such as a single can per day,” Liu said.

He added that these findings challenge the common belief that “diet” beverages are harmless.
Liu outlined possible biological mechanisms, saying that high sugar content in SSBs can spike blood glucose and insulin, promote weight gain, and increase uric acid levels, all of which contribute to liver fat accumulation. LNSSBs, he said, may affect liver health by altering the gut microbiome, disrupting satiety, driving sweet cravings, and potentially stimulating insulin secretion.

The study emphasised that limiting both SSBs and LNSSBs is crucial for liver and metabolic health. According to the researchers, replacing either beverage with water reduced MASLD risk by 12.8 per cent for SSBs and 15.2 per cent for LNSSBs, while substituting one type of soft drink for the other offered no benefit.

“The safest approach is to limit both sugar-sweetened and artificially sweetened drinks. Water remains the best choice as it removes the metabolic burden, prevents fat buildup in the liver, and keeps the body hydrated,” he said.

He added that further research will focus on understanding how sugar and its substitutes interact with the gut microbiome and contribute to liver disease through long-term randomised and genetic studies.