"The Belief That 'Zero Sugar = Harmless' Was a Misunderstanding — Does Your Liver Get Fat Every Time You Drink? The Reality of Artificial Sweeteners"

The Day "Zero" Shattered the Safety Myth——New Insights on Diet Drinks and Liver Risk

"Zero Sugar" and "Zero Calories." Labels that have spread as symbols of health consciousness are now quietly being re-evaluated. In October 2025, a large-scale study reported at the United European Gastroenterology Week (UEG Week) in Berlin suggested that not only "sugar-sweetened" but also "artificially sweetened" soft drinks could increase the risk of developing metabolic dysfunction-associated steatotic liver disease (MASLD, formerly known as NAFLD) associated with liver fat accumulation. The study tracked over 120,000 participants from the UK Biobank for more than 10 years, highlighting the impact that the choice of a daily "one drink" could potentially have on the future of one's liver, making headlines and spreading across social media worldwide.Fox Newsueg.eu

Here's a summary of the study: The group that consumed a high amount of sugar-sweetened beverages (SSB) saw about a 50% increase in MASLD risk, while the group that consumed a high amount of low/no-sugar-sweetened beverages (LNSSB, commonly known as diet drinks) saw about a 60% increase. A substitution analysis indicated that replacing these drinks with water could reduce the risk by about 14-15%. It is important to note that this study is observational and cannot definitively establish causation, and it also acknowledges limitations such as self-reported intake.Fox News

Fox News reported that "the risk increase was greater for diet drinks." The key points are: ① The announcement was made at UEG Week (Berlin) ② The study involved over 120,000 participants tracked for 10 years ③ SSB showed about a +50% risk, LNSSB about +60% ④ Replacing with water reduced the risk ⑤ It is a pre-peer-reviewed conference presentation.Fox News

This result is not an isolated report. In recent years, studies indicating the metabolic effects of artificially sweetened beverages have been accumulating, and related research using UK Biobank data has shown findings linking both artificial and sugar sweeteners to NAFLD-related outcomes.UK BiobankScienceDirect

Why Does "Zero" Affect the Liver?——Possible Mechanisms

• Impact on Gut Microbiota: Artificial sweeteners may alter the composition and metabolism of gut bacteria, potentially affecting liver lipid metabolism and inflammation.Fox News

• Changes in Taste Perception and Eating Behavior: The hypothesis that strong sweet stimuli activate the reward system, increasing sweet preferences and total caloric intake.Fox News

• Disruption of Insulin Response: Some studies suggest that even artificial sweeteners may affect insulin secretion and glucose metabolism indicators.Fox News

These are still at the hypothesis stage, and multiple factors are likely involved. In any case, the simple equation of "replacing sugar with artificial sweeteners solves everything" does not hold true.

Risk as a Function of "Quantity" and "Habit"

The hazard ratios in this study (SSB about 1.50, LNSSB about 1.60) are based on the premise of a "habit" of consuming the equivalent of one can (about 330g/day) or more daily. Occasional small intake a few times a week is different from a regular habit. The important thing is to "modify the habit."Drugs.com

Substitution Strategy: Water as the Optimal Solution

It was reported that replacing "sugar-containing→diet" with "both→water" contributed most to reducing risk. The key is not a "lateral slide" of high-risk behavior but a "downward shift." Specifically, replacing soft drinks at lunch with unsweetened sparkling water, flavored lattes at cafes with straight coffee + unsweetened milk, and energy drinks with herbal tea are effective "realistic substitutions."Drugs.com

How Did Social Media React?——Three Points of Discussion

Immediately after the conference presentation, discussions heated up in health communities on Reddit and posts on Threads. These can be generally categorized into the following three types.Reddit

1. "Correlation, Not Causation" Group
   Critics pointed out, "It's an observational study with self-reporting. There may be confounding factors like low health awareness or past dietary habits." This is a limitation acknowledged by the conference, and peer-reviewed papers and replication studies are needed.Fox News

2. The End of the "Better Than Sugar" Myth
   Voices saying, "The reassurance that diet drinks are 'relatively better' has been shattered," and "We should reconsider zero labeling regulations and advertising guidelines." Multiple media outlets emphasized the "+60% for diet drinks" in their headlines, accelerating the spread.EatingWell

3. Convergence on Practical Advice
   Numerous suggestions emerged, such as "Ultimately, increasing water is the answer" and "Unsweetened sparkling water and unsweetened tea are realistic." Media articles repeatedly introduced the effects of water substitution, showing signs of becoming established as a lifestyle practice.Medical News Today

Stance of Companies and Experts

Fox News noted, "We have sought comments from the U.S. beverage industry association," but no response was provided at the time of publication. In any case, considering recent international trends in regulation, labeling, and advertising expressions (such as high-sugar beverage taxes and front-label displays), the proactive message of "zero = harmless" is becoming risky.Fox News

Meanwhile, media for clinicians are beginning to organize points of caution in patient guidance, considering findings of increased liver-related mortality risk from diet drinks and relative risk reduction through water substitution.Medscape

"Implementation Guide" for Readers

• Reevaluate Your Daily Drink: First, self-check if you have a "daily one drink" habit. If so, switch to unsweetened options.Drugs.com

• Taste Acclimatization: It takes 2-3 weeks to get used to the taste of unsweetened drinks. Gradually transition from flavored unsweetened sparkling (no sweeteners) to plain water.

• Avoid "Rewarding": Beware of the substitution effect where other intakes increase due to the "zero-calorie" "license."

• Consult with Healthcare Providers: The optimal solution varies depending on existing conditions (diabetes, dyslipidemia, liver disease) and medications. Understand that this evidence is from observational studies and does not directly dictate individual treatment plans.Fox News

Current State of Evidence and the Next Steps

This announcement is at the conference proceedings stage (pre-peer review). In the future, detailed findings will be published as a paper, focusing on rigorous adjustment for confounding, dose-response, and subgroup (BMI, gender, existing metabolic diseases) verification. Concurrently, **randomized controlled trials (beverage substitution interventions) and mechanism studies (gut microbiota and liver lipid metabolism)** will advance. The consistency with past research supports the rationale for making "low-risk choices" in daily life.UK Biobank