Drinking at least one sugar-sweetened beverage a day doubles the risk of developing stomach cancer, according to a new US study -- the first to establish a link between sugary drink consumption and gastric cancer in an American population.

Researchers tracked health and lifestyle data from 112,000 people over several decades, identifying 278 cases of gastric cancer among them.

Those who consumed one or more sugary drinks daily were twice as likely to develop the disease compared with people who had less than one serving a month, reports The Independent.

The link was held for both men and women.

The risk was sharply higher for women in particular.

Drinking more than one sugary beverage a day -- including punch, lemonade, and sports drinks -- was associated with nearly three times the gastric cancer risk compared with those who rarely consumed such drinks.

Fructose, the primary sweetener found in most of the beverages consumed by study participants, appeared to be the main driver of the elevated risk.

"Gastric cancer is the fifth leading cause of cancer death worldwide, but we've known very little about how diet might contribute to this cancer," said Andrew Chan, lead author of the study, published in the journal Gastro Hep Advances.

"This is the first study to demonstrate an association between sugar-sweetened beverage intake and gastric cancer in a US population."

By contrast, higher consumption of artificially sweetened and low-calorie carbonated drinks showed no association with greater gastric cancer incidence, suggesting diet beverages may be a lower-risk alternative for those unwilling to cut out fizzy drinks entirely.

The study also examined the potential role of Helicobacter pylori -- a bacterium already known to raise gastric cancer risk -- by assessing H pylori status in a subset of 940 participants.

No connection was found between sugary drink consumption and H pylori infection, indicating the two risk factors appear to operate independently.

Researchers were careful to note the study's limitations.

The findings are observational and stop short of establishing a direct causal relationship between sugary drinks and stomach cancer.

Participant data on H pylori status and family history of gastric cancer were also limited, leaving room for further investigation.

Gastric cancer ranks among the deadliest cancers globally, yet dietary contributors have remained poorly understood -- making the findings a significant, if preliminary, addition to the field.