(C) Insight

SEOUL — For generations, the act of sharing a single pot of jjigae (stew) has been a symbol of Korean jeong (affection) and communal bonding. However, a groundbreaking large-scale study suggests that this cherished culinary tradition may be a silent contributor to South Korea's high rates of gastric cancer by facilitating the spread of Helicobacter pylori.

The 6.8 Million Person Deep-Dive
A research team led by the Department of Preventive Medicine at Chung-Ang University College of Medicine recently published a definitive study in the international journal BMC Cancer (December 2025/January 2026 issue). Analyzing health insurance data from over 6.86 million adults (aged 40–74) who participated in the 2018 National Cancer Screening Program, the team found that H. pylori infection increases the risk of developing gastric cancer by a staggering 6.40 times compared to non-infected individuals.

Gastric cancer remains the fifth most common cancer in South Korea, with approximately 29,000 new cases reported annually. Notably, the incidence rate in men is nearly double that of women, a gap researchers attribute to higher rates of smoking, alcohol consumption, and exposure to infection.

Quantifying the 'Correa Pathway'
The study is the first of its scale to quantify the "Correa Pathway"—the stepwise progression where H. pylori triggers chronic inflammation, leading to atrophic gastritis, intestinal metaplasia, adenoma, and finally, adenocarcinoma.

Key findings from the causal mediation analysis include:

Precancerous Risk: Infected individuals had a 1.41-fold higher risk of atrophic gastritis/intestinal metaplasia and a 5.81-fold higher risk of gastric adenoma.
The Adenoma Connection: Approximately 36% of the total effect of H. pylori on gastric cancer was found to be mediated specifically through adenoma.
Progression: Among those already suffering from precancerous lesions, adenomas explained 44% of the subsequent progression to full-blown cancer.

The "Spoon-Sharing" Cultural Factor
H. pylori is classified as a Group 1 carcinogen by the World Health Organization (WHO). It thrives in the stomach lining and is primarily transmitted through oral-to-oral or fecal-to-oral routes.

"In Korea, the habit of multiple people dipping their spoons into a shared stew or side dish is a major vector for transmission," the researchers noted. While the infection rate among Koreans over 16 has dipped to about 44% in recent years, it remains significantly higher than in many Western nations, where individual plating is the norm.

Early Detection: The Best Defense
Because early-stage gastric cancer often mimics common indigestion or heartburn, it is frequently ignored. Experts warn that by the time severe symptoms like weight loss, anemia, or upper abdominal pain appear, the cancer may have already progressed.

To mitigate risk, medical professionals recommend:

Hygienic Dining: Using serving ladles and individual plates to prevent saliva exchange.
Dietary Discipline: Reducing intake of highly salted, processed, or charred foods.
Regular Screening: Participating in biennial upper endoscopies for those over 40, even in the absence of symptoms.
As South Korea continues to grapple with its status as a high-incidence zone for gastric cancer, this study underscores that preventing H. pylori infection—and treating it early—is not just a medical necessity, but a cultural shift waiting to happen.