SOMERVILLE, Mass., Aug. 20 (Nationwide Times) — A large U.S. study found that people who reported drinking at least one sugar-sweetened beverage a day had 2.45 times the risk of developing stomach cancer as those who consumed such drinks less than once a month.
The finding does not mean that a daily soda or other sugary drink will cause cancer. The study was observational, meaning researchers identified an association in health records and dietary reports but could not prove cause and effect. Still, the results add to evidence that frequent consumption of beverages with added sugar may be an important health factor.
For people weighing an everyday drink choice, the study’s message is about patterns over time rather than a single beverage. The researchers examined regular consumption of drinks such as carbonated beverages, punch, lemonade and sports drinks. Some summaries of the study also included regular soda, energy drinks and juice with added sugars.
What did the study find?
Researchers from the Mass General Brigham Cancer Institute analyzed data from 112,284 participants in the U.S. Nurses’ Health Study and the Health Professionals Follow-Up Study. The data covered several decades, from 1986 through 2022, and included 278 documented cases of gastric cancer, according to the study summary issued by Mass General Brigham.
The researchers reported that greater total fructose intake was also associated with a higher incidence of gastric cancer. Fructose is a sugar found naturally in foods such as fruit, but it is also added to many sweetened drinks and foods.
Among women in the Nurses’ Health Study, consuming more than one sugar-sweetened beverage per day was associated with a 3.04-fold higher risk compared with very rare consumption. The association was reported in both women and men, with summaries of the study describing an approximately threefold association among women and roughly twofold association among men.
The study did not find that low-calorie carbonated beverages, described in the research as artificially sweetened beverages, were associated with increased stomach-cancer incidence after adjustment for other factors. That result does not show that artificially sweetened drinks reduce cancer risk.
Why the numbers need context
“2.45 times higher risk” is a relative comparison. It does not say that 2.45 out of every 100 daily drinkers will develop stomach cancer, or show how many additional cases were linked to daily consumption.
The 278 cases were counted across the entire study group and study period. The results available from Mass General Brigham do not provide the absolute risk for each beverage-consumption category or the difference in cases between groups. Because stomach cancer was uncommon in the analyzed population, the absolute risk for an individual participant may be much smaller than the relative-risk figure suggests.
The study also does not establish whether the association was caused by sugary beverages themselves, fructose, another dietary pattern or a related factor. Researchers adjusted for other potential risk factors, but the available study summary does not list every factor included in the analysis or provide the study’s confidence intervals and full statistical model.
What the study can—and cannot—show
The senior author, Andrew T. Chan, a gastroenterologist and epidemiologist at Mass General Brigham and Massachusetts General Hospital, said the study could not prove cause and effect. He described the result as an association requiring more research to determine whether the relationship is truly causal.
The study was published in Gastro Hep Advances under the title “Association between sugar-sweetened and artificially sweetened beverage intake and gastric cancer incidence.” Its U.S. cohort design allowed researchers to examine beverage habits and later cancer diagnoses over many years, but it did not involve assigning participants to drink specific beverages.
That distinction is important in health research. A randomized trial could provide stronger evidence about causation, but such a trial would be difficult and potentially unethical for a cancer outcome that can take years to develop. Observational studies can identify patterns that merit further investigation, while leaving open the possibility that other differences between groups helped explain the result.
The findings therefore do not establish that occasional consumption causes stomach cancer, nor do they provide an individual cancer prediction. They add a potential concern about frequent sugar-sweetened beverage intake to a broader area of research on diet, added sugars and cancer risk.
