Even light drinkers at risk: 12-year study finds starting or increasing alcohol use fuels stomach cancer

A large-scale study by Seoul National University Bundang Hospital (SNUBH) has found that starting to drink alcohol or increasing consumption over time significantly raises the risk of developing stomach cancer.

The findings suggest that not only total alcohol intake but also behavioral changes in drinking habits should be closely monitored and managed to prevent gastric cancer.

A research team led by Professors Kim Na-young and Choi Yong-hoon from the Department of Gastroenterology at SNUBH, and Doctor Jang Ji-eun from the Division of Clinical Research at National Cancer Center, analyzed health screening data from the National Health Insurance Service involving 310,192 adults aged 40 and older.

Participants were categorized by daily alcohol intake into three groups: light (less than 15 g for men, 7.5 g for women), moderate (15–29.9 g for men, 7.5–14.9 g for women), and heavy (30 g or more for men, 15 g or more for women). They were followed for an average of about 12 years.

The study found that an increase in alcohol consumption, regardless of the current intake level, was clearly associated with a higher risk of stomach cancer, while reducing or stopping alcohol intake lowered the risk.

For example, individuals who began drinking after previously abstaining had a 14 percent higher risk of stomach cancer, even if they consumed only small amounts. Conversely, moderate drinkers who reduced their intake to light levels saw their risk decrease by about 20 percent.

The findings also revealed gender-specific patterns. Among men, non-drinkers had about a 10 percent lower risk of stomach cancer compared with those who continued drinking, while those who increased their consumption faced about a 10 percent higher risk.

In women, the overall correlation was weaker, but those who moved from non-drinking to heavy drinking saw their risk nearly double, underscoring the dangers of binge drinking.

According to the researchers, this is the first long-term study to detail how changes in drinking habits, rather than absolute intake alone, affect the likelihood of stomach cancer. The findings highlight the importance of tailored public health interventions that reflect gender differences and behavioral changes.

“Not only the amount of alcohol consumed but also recent changes in drinking patterns are closely linked to stomach cancer risk,” Professor Kim said. “Continuously improving lifestyle habits through moderation or complete abstinence plays a key role in preventing the disease.”

People who have previously had early-stage stomach cancer removed through endoscopy or those with risk factors such as family history or smoking should absolutely refrain from drinking, or at least make a strong effort to minimize their alcohol intake, Kim added.

The study was recently published online in Cancer Research and Treatment, the official journal of the Korean Cancer Association.