Sugar-Sweetened Drinks Linked to Chronic Liver Disease, Liver Cancer

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Do you find yourself drinking a sugar-sweetened beverage every day? Be cautious, as this habit could increase the risk of chronic liver disease and even liver cancer.

It’s widely known that consuming sugar-sweetened drinks can contribute to obesity and insulin resistance, but a recent prospective cohort study published in the Journal of the American Medical Association (JAMA) has now linked them to liver disease.

The study shows that individuals who regularly consume sugar-sweetened drinks face an astonishing 85 percent higher likelihood of developing liver cancer and a 68 percent higher risk of mortality from chronic liver disease than those who consume fewer sugar-sweetened drinks.

Elevated Risks of Liver Cancer, Liver Disease

This study was led by scientists from Harvard Medical School and Brigham and Women’s Hospital, and it drew data from a comprehensive prospective clinical database in the United States: the Women’s Health Initiative. The database has been gathering information from a cohort of more than 160,000 postmenopausal women aged 50 to 79. The information collection concluded in 2020 after a follow-up period of approximately 21 years.

“Epidemiological studies on dietary factors and liver cancer and chronic liver disease mortality are limited,” the researchers emphasized in the report. “To our knowledge, this is the first study to report an association between sugar-sweetened beverage intake and chronic liver disease mortality.”

Participants completed the survey questionnaire detailing their consumption of sugar-sweetened and artificially sweetened drinks, excluding fruit juices. These individuals were divided into three groups:

• Women who consumed three servings or less per month.
• Women who drank one to six servings per week.
• Women who drank one or more servings per day (with one serving equivalent to 12 ounces or 355 milliliters, roughly the size of a standard beverage can).

The findings revealed that women who consumed one or more servings of sugar-sweetened drinks daily had an 85 percent higher risk of developing liver cancer than those who drank three servings or less per month. Their mortality rate due to chronic liver disease was 68 percent higher.

In the study, “chronic liver disease” refers to conditions such as nonalcoholic fatty liver disease, cirrhosis, liver fibrosis, alcoholic liver disease, and chronic hepatitis. During the calculation, potential factors that could influence liver disease, including age, ethnicity, education level, smoking and alcohol consumption habits, and body mass index, were taken into account.

Known risk factors for liver cancer include hepatitis B and hepatitis C infections, metabolic disorders, excessive alcohol consumption, and foods contaminated with aflatoxins, such as peanuts and corn.

“However, approximately 40 percent of patients with liver cancer do not have these risk factors. ... Therefore, it is important to identify dietary risk factors for liver cancer and chronic liver disease mortality,” the researchers said in the report.

The Impact of Sugar-Sweetened Drinks on the Liver

Other studies have also corroborated the damaging effects of sugar-sweetened drinks on the liver.

A prospective European cohort study revealed that individuals who consume more than six servings of soft drinks per week face a notably higher risk of hepatocellular carcinoma (the most common form of liver cancer) by 83 percent compared to those who consume fewer than one serving. The risk increases by 6 percent for each additional serving per week. Another study conducted in the United States indicated that drinking sugar-sweetened soda is associated with an 18 percent increase in the risk of liver cancer.

Research has also demonstrated a link between sugar-sweetened drink consumption and nonalcoholic fatty liver disease onset. A systematic review and meta-analysis published in the European Journal of Nutrition revealed that individuals who consumed the highest amounts of sugar-sweetened drinks had 40 percent increased odds of developing nonalcoholic fatty liver disease compared to those who consumed the least. Another study in 2022 proposed that individuals who frequently consume sugar-sweetened drinks have 2.53 times increased odds of developing nonalcoholic fatty liver disease compared to those who rarely drink such beverages.

High consumption of sugar-sweetened drinks is linked to both increased chronic liver disease mortality risk and liver cancer risk. New Africa/Shutterstock

In the recent JAMA study mentioned earlier, the authors concluded that the main factors contributing to the threat to liver health from sugar-sweetened drinks are the following:

• Sugar-sweetened drinks may contribute to obesity and spikes in blood sugar, leading to insulin resistance—all of which are risk factors for liver cancer and liver disease.
• Sugar-sweetened drinks contain significant amounts of fructose, which can lead to the buildup of liver fat and, in turn, potentially trigger the development of liver cancer.
• Consuming sugar-sweetened drinks can lead to abnormal blood lipid levels and have an adverse impact on gut microbiota, which, in turn, affects liver health.
• Metabolites produced after consumption (such as taurine and phenylalanine) are linked to liver cell carcinoma.
• Sugar-sweetened drinks contain various chemicals (such as caramel color and additives) that may harm the body.

Researchers Urge Caution

While establishing a clear link between sugar-sweetened drinks and liver disease, the results of this study indicate that the consumption of artificially sweetened drinks “was not associated significantly” with liver cancer or chronic liver disease mortality.

“This finding is not that surprising,” the two lead authors of the study, Longgang Zhao, a postdoctoral research fellow at the Channing Division of Network Medicine, Brigham and Women’s Hospital, Harvard Medical School, and Xuehong Zhang, associate professor at Harvard Medical School and associate epidemiologist at Brigham and Women’s Hospital, said during an interview with The Epoch Times. They explained this is because “the consumption level of artificially sweetened beverages is low in this population (postmenopausal women), and the sample size of liver cancer and death due to chronic liver diseases is relatively small.”

However, they emphasized that “these results should be interpreted with caution”—in other words, the results don’t mean artificially sweetened drinks are safer than sugar-sweetened drinks.

“Additionally, other studies also indicate that artificially sweetened beverages have been associated with a higher risk of obesity, Type 2 diabetes, all-cause mortality, hypertension, and cardiovascular disease incidence,” the authors said.

Therefore, further research is needed.

This study noted that substituting one serving of sugar-sweetened drink with one serving of coffee or tea daily, while lacking statistical significance, is linked to a decrease in the incidence of liver cancer and chronic liver disease mortality.

‘Low-Sugar Diet’ as a Public Health Strategy

This is a high-quality study that “points to a link between sugar and liver disease and liver cancer,” said Dr. Jason Fung, author of “The Obesity Code” and “The Cancer Code” and a nephrologist specializing in reversing Type 2 diabetes, acknowledging the study’s findings in an interview with The Epoch Times.

However, he also noted that “it’s an observational study, which is less robust than a controlled trial.”

The authors admitted that this research shouldn’t be hastily assumed to imply causation.

Due to the study questionnaire’s design, the differentiation of types of sweetened drinks is limited, and it isn’t possible to specifically categorize artificial sweeteners.

However, Mr. Zhang and Mr. Zhao said, “If our study findings are confirmed, reducing the consumption of sweetened beverages could become a public health strategy to alleviate the burden of liver disease.”

Dr. Fung said, “We should be promoting a diet lower in sugar, rather than the previous confused nutritional messaging of just reducing calories and reducing fat.”

Mr. Zhang and Mr. Zhao explained, “Given that the study focused on postmenopausal women, studies involving men and younger women are needed to examine the associations more comprehensively. Furthermore, more research is needed to elucidate the potential mechanisms (linking sugar-sweetened-drink consumption to liver disease and liver cancer) by integrating genetics, animal/experimental studies, and -omics [genomics, metabolomics, metagenomics, and so forth] data.”