Fizzy drinks and sweet juices have never enjoyed a glowing reputation when it comes to healthy living.
After all, they commonly take the blame for poor dental health, weight gain, and energy crashes. While most of us know they’re not doing our bodies any favours, fresh findings provide a much more serious reason to reconsider cracking open that regular afternoon can.
A major US study tracking thousands of people has uncovered a direct correlation between frequently reaching for sugary drinks and a considerably higher chance of developing stomach cancer. The research marks the first time scientists have pinpointed such a clear connection for this specific illness, raising fresh questions about how liquid sugars affect the gut. Here’s what the data actually found, and what it means for your daily drinking habits.
The study findings were pretty disturbing for anyone who regularly enjoys sugary drinks.
Researchers publishing in the journal Gastro Hep Advances discovered that people who drank at least one sugary beverage a day were roughly two and a half times more likely to develop stomach cancer compared with those who avoided sugary drinks altogether. Andrew T. Chan, a gastroenterologist and senior author on the study from Massachusetts General Hospital, described it as the first piece of research to properly demonstrate this kind of link in a US population. He also pointed out how little has previously been understood about how diet influences stomach cancer specifically, despite it ranking as the fifth leading cause of cancer death globally.
This particular cancer has been poorly understood.
Sugary drinks already carry a long list of known health risks. They’ve been tied to well over 180,000 deaths every year worldwide, alongside raised risks of type 2 diabetes, obesity, and several other cancers including breast, liver, and colorectal cancer. Stomach cancer specifically, though, has proven trickier to pin down. Earlier attempts to investigate a possible connection between sugary drinks and gastric cancer produced inconclusive results, largely because the available data simply wasn’t extensive enough to draw firm conclusions from.
How the study was carried out
To get around that limitation, the research team combined data from two long-running studies, pulling together information on more than 112,000 participants in total. Every two years, those taking part filled in detailed questionnaires covering their diet, including how often they drank sugar-sweetened beverages such as fizzy drinks, fruit punch, lemonade, and sports drinks, alongside broader lifestyle habits, medical history, and any diagnosed conditions.
Across the decades the study ran, spanning from the mid-1980s through to 2022, 278 cases of gastric cancer were recorded among the participants. After accounting for other potential risk factors, people who drank at least one sugary beverage a day, defined as a standard 237ml serving, were found to be 2.45 times more likely to develop the disease than those who didn’t drink sugary beverages at all.
The risk wasn’t the same for everyone.
Interestingly, the increased risk showed up differently between men and women. Women who drank at least one sugary beverage daily saw roughly triple the risk of developing gastric cancer compared with non-drinkers, while men saw their risk roughly double. Both figures are substantial, but the gap between the sexes is something researchers will likely want to explore further in future work.
What about diet drinks?
Given the ongoing debate and headlines around artificial sweeteners potentially being linked to cancer, it’s important to point out what this particular study did and didn’t find. The researchers didn’t identify any connection between artificially sweetened beverages and gastric cancer risk in this dataset. That doesn’t necessarily settle the wider debate around sweeteners, but within the scope of this specific research, it was sugar itself, not sugar substitutes, that showed the link.
All things considered, this doesn’t prove sugary drinks cause cancer.
It’s important to be clear about what this type of study can and can’t tell us. This was an observational study, meaning it can identify patterns and associations in the data, but it can’t prove that sugary drinks directly caused the cancer cases recorded. Plenty of other factors could have played a role in these outcomes that the study wasn’t able to fully account for.
There were also some notable gaps. The researchers had limited data on Helicobacter pylori infection, a type of stomach bacteria already known to raise gastric cancer risk, which makes it harder to fully separate that influence from the effects of sugary drinks. Full family history and detailed health records weren’t available for every participant either, both of which could realistically affect the results.
How sugar might actually cause this kind of damage
Working out exactly how sugary drinks might contribute to stomach cancer wasn’t part of this particular study, but the researchers have a few working theories that need further exploration. Possible mechanisms include weight gain, insulin resistance, imbalances in steroid hormones, chronic inflammation, damage to DNA, and disruption to the natural balance of bacteria in the gut. None of these have been confirmed as the specific cause behind the findings, but they give future researchers a clear starting point.
So, where do we go from here?
The researchers themselves are calling for further studies to confirm these findings and dig deeper into the biological mechanisms that might be driving this connection. Given how common sugary drinks are in most people’s daily routines, and how serious a diagnosis like gastric cancer can be, this is very much an area worth watching closely as more research emerges.
