Regular and diet soft drinks, long seen as routine beverages, may significantly increase the risk of fatty liver disease and liver-related death. A new large-scale study presented at UEG Week 2025 revealed that both sugar-sweetened beverages (SSBs) and low- or no-sugar-sweetened beverages (LNSSBs) were tied to higher chances of developing metabolic dysfunction-associated steatotic liver disease (MASLD). This research challenges the widespread assumption that “diet” sodas represent a healthier alternative to sugary ones.
Analyzing data from 123,788 adults in the UKBiobank who initially showed no signs of liver problems, scientists assessed drink habits through repeated 24-hour dietary questionnaires. Over a median follow-up of 10.3 years, 1,178 participants developed MASLD and 108 died from liver-related causes. Importantly, those consuming more than 250 grams of any type of soft drink per day faced markedly higher risks of liver issues.
The Numbers Behind the Risk
Researchers found that participants who drank LNSSBs faced a 60% greater likelihood of developing MASLD compared to non-drinkers, while those who consumed SSBs had a 50% higher risk. Although sugar-sweetened beverages were not directly linked to liver-related mortality, diet versions surprisingly were. Both categories also contributed to higher liver fat content, revealing that no type of soda is truly risk-free.
This finding underscores growing concerns among scientists that beverages replaced with artificial sweeteners may disrupt metabolism in ways that mimic or even amplify sugar’s harmful effects. The data now suggest that both regular and diet sodas impose measurable stress on the liver, potentially accelerating metabolic diseases.
Understanding MASLD: A Silent Epidemic
Formerly known as non-alcoholic fatty liver disease (NAFLD), MASLD occurs when excess fat builds up in liver tissue without alcohol being a factor. Over time, this fat accumulation triggers inflammation, causing pain, fatigue, and reduced appetite, ultimately leading to liver scarring or even failure if untreated. Affecting over 30% of the global population, MASLD has become the most common chronic liver condition worldwide and one of the fastest-growing causes of liver-related deaths.
Researchers are increasingly connecting modern dietary patterns, dominated by sweetened beverages, to this surge in metabolic dysfunction. The study’s evidence reinforces the urgency of limiting sugary and sugar-free drinks alike as part of public health strategies aimed at preventing chronic metabolic diseases.
“Diet” Drinks Are Not Harmless
Lead researcher Lihe Liu of the University of Hong Kong highlighted that public perception of “diet” beverages as healthy alternatives may be dangerously outdated. According to Liu, even moderate LNSSB consumption—such as a can per day—was associated with a notable MASLD risk increase.
“SSBs have long been under scrutiny,” Liu explained, “yet their artificially sweetened counterparts are consumed widely under the assumption that they are safer. Our study indicates otherwise, revealing increased liver risks even at modest intake levels.”
This pattern indicates that artificially sweetened drinks may affect metabolic function differently but harmfully—altering gut microbiota, heightening cravings for sweetness, and potentially stimulating insulin production unexpectedly.
Biological Mechanisms Behind the Findings
The study provides insight into how each beverage type may damage the liver through distinct biological pathways. Sugar-sweetened beverages flood the body with glucose, spiking insulin levels and promoting fat storage while contributing to elevated uric acid accumulation that stresses the liver. In contrast, diet beverages alter appetite regulation, weaken the gut’s microbial composition, and disrupt satiety cues—leading to overeating and increased calorie intake overall.
Both processes contribute to fat accumulation and metabolic dysfunction, linking habitual beverage choices to broader health risks including obesity, insulin resistance, and cardiovascular disease. Over time, these disturbances collectively set the stage for liver inflammation, fibrosis, and eventual liver failure.
Water: The Simplest and Safest Alternative
In the same study, individuals who substituted their soft drink intake with water experienced significantly reduced MASLD risks—by 12.8% for sugar-sweetened beverages and 15.2% for artificially sweetened ones. Crucially, replacing one type of soda with the other did not yield any protective effect.
Liu stressed that water remains the safest and most effective hydration option, noting, “Limiting both types of beverages removes unnecessary metabolic stress and prevents fat accumulation in the liver while maintaining hydration.” For health-conscious consumers, the message is clear: the human body benefits most from natural fluids rather than manufactured sweetness.
Implications for Public Health and Policy
Given MASLD’s growing prevalence and its associations with diet-driven metabolic disorders, health authorities may soon face heightened pressure to regulate or discourage soft drink consumption more explicitly. Taxes on sugary drinks, educational campaigns emphasizing whole-food diets, and better labeling of artificial sweeteners could form part of future preventive strategies.
This latest evidence also signals to global policymakers that tackling obesity and diabetes epidemics requires confronting beverage marketing and accessibility directly. Lifestyle modification, especially through dietary choices, remains a powerful yet underutilized weapon against the silent progression of liver disease.
Expanding Research Horizons
The researchers plan to expand their work by exploring the causal biological mechanisms that link these beverages to liver pathology more precisely. They aim to conduct long-term randomized trials and genetic studies that analyze how sugars and artificial sweeteners interact with the gut microbiome, hormonal responses, and metabolic regulation.
Such investigations will help define whether artificial sweeteners directly induce liver stress or act as proxies for other unhealthy lifestyle patterns. Experts anticipate that understanding these connections could inform new clinical guidelines on beverage formulations, marketing, and consumption recommendations globally.
A Wake-Up Call for Everyday Consumption
This study serves as a sobering reminder that modern dietary habits, influenced by convenience and preference for sweetness, carry hidden metabolic costs. Both regular and “diet” soft drinks may threaten liver health in ways once overlooked, urging consumers to reevaluate their beverage choices quickly.
While the global beverage industry markets diet sodas as guilt-free thirst quenchers, scientific consensus is shifting toward skepticism. The evidence now demonstrates that no sweetened drink—whether sugar-based or artificially formulated—escapes metabolic consequences entirely. Only water, plain or sparkling, offers genuine protection against the cascade of health issues tied to excessive sweetener intake.
As researchers continue to explore how food choices influence longevity and disease, this study reinforces one timeless lesson: our bodies were designed for balance, not constant sweetness. Limiting soft drinks in all forms remains one of the simplest steps toward preserving a healthy liver, stable metabolism, and longer life.
