Stomach cancer, also known as gastric cancer, has been known to affect countries and genders disproportionately. Specifically, according to Yahoo, the countries with the highest rates of stomach cancer in the world are Mongolia, Japan, South Korea, Tajikistan, Kyrgyzstan, and China. Interestingly, all of these countries are located in Asia, and most are developing countries. Additionally, according to the American Cancer Society, males are generally at a higher risk of developing stomach cancer compared to females. These trends have piqued the interest of the scientific community, but a concrete explanation has constantly eluded researchers, leaving people wondering what factors could be attributed to these observations.
That said, recent research may provide more clues to explain these observations. According to a report on NBC, new research suggests that East Asian people are more likely to develop an “aggressive type of stomach cancer because of their higher likelihood of alcohol intolerance.” In their paper, the researchers “associate lower alcohol tolerance with higher risk of diffuse stomach cancer, a rarer type of gastric cancer that affects more than one area of the stomach.” Tatsuhiro Shibata, a co-author of the research paper, hopes that the findings will facilitate further research and make it easier for researchers to identify patterns in stomach cancer cases.
East Asian people are also much more likely to have a unique genetic mutation that makes it harder for alcohol to be metabolized. This mutation explains why many Asians appear flushed after drinking, a phenomenon known as “Asian Glow.” According to Ajay Goel, a gastrointestinal cancer researcher at City Hope Medical Center, “Many East Asians’ inability to properly process alcohol enables it to sit in the stomach for a long time, making frequent drinkers more likely to develop chronic gastritis.” Eventually, he notes, “over years and years of repeated exposure, these patients tend to get an increased incidence of gastric cancer.” Goel also thinks that behavioral differences may explain why gastric cancer cases are more common in men than in women, as data from an older report shows that East Asian men tend to consume much more alcohol than East Asian women.
Dr. William Dahut, a chief scientific officer of the American Cancer Society who was not involved in the study, states that the study “is the first extensive genomic analysis of gastric cancer,” involving almost 1,500 stomach cancer patients in Japan, China, South Korea, Singapore, and the United States. “There is an interesting combination between mutation development and a specific genotype in East Asians, which interferes with alcohol metabolism,” Dahut states. “It seems like having that genotype, they’re more likely to develop a specific mutation of the tumor.”
Additionally, another reason Asian countries are more susceptible to stomach cancer may be due to their diet and cultural traditions. According to the American Heart Association, Asian diets, while having many healthy aspects, may contain high levels of sodium from condiments like soy sauce and unhealthy fats from cooking oil. Another recent study in the journal Nature suggests “that lifestyle factors, particularly a high-sodium diet and smoking among males, play important roles in the gastric cancer burden.” Since males are more likely to be exposed to drinking and smoking habits, they are at a higher risk for developing stomach cancer, as “both of these are also risk factors for other non-communicable diseases, and minimizing exposure to these factors is generally recommended in guidelines for a healthy lifestyle.”
Although there isn’t much additional research on how cultural differences directly impact stomach cancer rates, there has been research conducted on the implications of varying eating and lifestyle habits. According to an article by the World Cancer Research Fund, there is strong evidence that consuming alcoholic drinks, eating salt-preserved foods, or being obese increases the risk of stomach cancer. Additionally, there is some evidence that eating grilled or barbecued meat or fish, processed meat, or not eating enough fruits may also increase the risk of stomach cancer. Although there is no denying that Asian diets prioritize healthiness and nutrition, the influence of Western culture in recent years and the spread of fast food restaurants may have caused people to resort to unhealthier diet options.
Overall, research provides valuable insights for scientists looking to detect patterns in stomach cancer cases. Although an exact cause-and-effect relationship hasn’t been determined, multiple studies have associated higher gastric cancer rates with eating, smoking, and drinking habits. Since current research on this topic mainly focuses on patients in China, Japan, and Korea (which are not representative of all the 48 Asian countries), more research is needed in other Asian countries such as Mongolia, Tajikistan, and Kyrgyzstan. By focusing more on the early indicators and patterns of gastric cancer cases, scientists and doctors can help improve patient diagnoses and early detection.
