Findings from a new study published in JAMA explored the effects of sugary beverage intake in 98,786 postmenopausal women over an average follow-up of 20.9 years.
They found that women who drank one or more servings daily of sweetened beverages—compared with those who consumed three or fewer per month—saw a significantly higher risk of liver cancer and chronic liver disease mortality.
The researchers did not find an association between artificially sweetened beverages and increased incidence of liver cancer, which experts find confounding.
New research published in the Journal of the American Medical Association (JAMA) shows an association between the consumption of sugar-sweetened beverages and a higher incidence of liver cancer and death from chronic liver diseases in postmenopausal women.
The researchers looked at 98,786 postmenopausal women aged 50 to 79, followed up for an average of 20.9 years. The women were enrolled in the Women’s Health Initiative from 1993 to 1998 across 40 clinical centers in the US. Follow-up continued through to March 1, 2020.
To understand the association, the researchers provided participants with a food frequency questionnaire. It was “administered at baseline and defined as the sum of regular soft drinks and fruit drinks (not including fruit juice); artificially sweetened beverage intake was measured at 3-year follow-up.”
The primary outcomes included liver cancer incidence and mortality due to chronic liver disease (specifically, non-alcoholic fatty liver disease, liver fibrosis, cirrhosis, alcoholic liver diseases, and chronic hepatitis). The researchers adjusted the confidence interval, which was required to be at 95%, for potential confounders, including demographics and lifestyle factors.
They found that, at baseline, 6.8% of women consumed one or more sugar-sweetened beverage servings per day. In comparison, 13.1% consumed one or more artificially sweetened beverage servings daily at a three-year follow-up. Over the course of 20.9 years, 207 participants developed liver cancer, and 148 died from chronic liver disease.
Those who drank more sweetened beverages (one or more servings per day) compared with those who drank fewer ( only three or fewer servings of sugar-sweetened beverages per month) saw a significantly higher risk of liver cancer (18.0 vs 10.3 per 100,000 person-years) and chronic liver disease mortality (17.7 vs 7.1 per 100,000 person-years).
The researchers also found that people who consumed one or more artificially sweetened beverages per day (compared with those who drank three or fewer artificially sweetened beverages per month) did not have significantly increased incidence of liver cancer (11.8 vs 10.2 per 100,000 person-years) or chronic liver disease mortality (7.1 vs 5.3 per 100,000 person-years).
“Future studies should confirm these findings and identify the biological pathways of these associations,” the researchers summarized—especially given that nearly 65% of adults in the US consume sugar-sweetened beverages daily, the authors underscored.
What the findings mean for you
Anton Bilchik, MD, PhD, a surgical oncologist and Chief of Medicine and Director of the Gastrointestinal and Hepatobiliary Program at Saint John’s Cancer Institute in Santa Monica, CA, tells MDLinx, “This is a fascinating study because we have an epidemic of fatty liver disease in this country…and [this study] provides some idea as to how we can prevent fatty liver disease and liver cancer. It’s extremely important.”
In fact, it’s estimated that non-alcoholic fatty liver disease—a condition in which fat builds up in the liver—is estimated to affect 24% of the US population, becoming the most common cause of chronic liver disease. Liver cancer leads to the deaths of an estimated 30,000 adults each year in the US, and it is a leading cause of cancer deaths in the US, according to the American Liver Foundation.
Bilchik also says that while the study didn’t look at obesity, obesity is associated with both fatty liver disease and liver cancer. “What this study would suggest, regardless of obesity, is that any postmenopausal woman should decrease sugar intake.”
Bilchik also notes the study’s additional focus on artificial beverages, which he finds most confounding. “What’s particularly interesting, and fairly controversial, is the issue of artificial sweeteners,” he says. “In this study, there’s no increase in risk from artificial sweeteners, suggesting that they’re safer. Yet, this completely contradicts what has been shown in [European studies], which is that artificial sweeteners are more likely to lead to cancers than regular sugar-sweetened beverages.”
For example, according to 2023 findings published in European Urology Open Science, researchers found that among 80,388 postmenopausal women, those who drank more artificially sweetened beverages were at higher risk of kidney cancer. A 2022 study in PLoS Medicine found that artificial sweeteners like aspartame and acesulfame-K were associated with increased cancer risk.
On the other hand, a 2022 meta-analysis published in the the Journal of Public Health found that “[c]onclusions remain controversial between the consumption of sugar and artificially sweetened beverages (SSBs and ASBs) and mortality,” but that high consumption of both ASBs and SSBs were significantly associated with a higher risk of cardiovascular disease (CVD) mortality and all-cause mortality.
2019 research published in Circulation also found that SSBs were associated with CVD mortality, but the association between ASBs and total and CVD mortality in women would require further research.
What this means for you
Bilchik suggests counseling patients to try to reduce their sugar intake. “When we see patients who ask, ‘What can I do to reduce the chances of cancer or fatty liver disease?’ this study confirms it: reduce sugar intake.”
Of course, he continues, sugar is found in many of the foods patients put on the dinner table, including fruit, wine, and plenty of other liquids and solids. So, he suggests that MDs tell patients, “Everything in moderation, recognizing that too much sugar is not only associated with liver disease, but also higher risk of cardiovascular disease, diabetes, and a variety of metabolic issues.”
Bess Berger, RDN, of Nutrition by Bess, says that she consistently sees how strongly sugar plays into everyone’s daily diet. “The [amount of] sugar in our diets has increased tremendously…While these studies are important and emphasize the gravity of sugar in women's diets, I think all people need to look at and address sugar. Doctors or dietitians not addressing sugar is like not addressing the elephant in the room.”