In China, people have a unique obsession with "eating". "China on the Tip of the Tongue" has traveled all over the country to find the delicacies of the world, and successfully aroused people's yearning for special cuisines from all over the world.
But in China, there is one cancer that is also closely related to "eating" - stomach cancer.
Stomach cancer is the second largest cancer on the mainland, after lung cancer.
According to the latest China Cancer Statistics Annual Report [1] released in 2018, the age-standardized incidence of gastric cancer is 19.51/100,000, while the incidence of gastric cancer in East China and Northwest China is as high as 24.3/100,000 and 32.0/100,000, respectively, which is much higher than the national level.
Previous data showed that the Liaodong Peninsula, Shandong Peninsula, Yangtze River Delta, Taihang Mountains and Hexi Corridor on the mainland are high-incidence areas for stomach cancer[2], while Liaoning, Fujian, Gansu, Shandong, Jiangsu and other places are provinces with high incidence of stomach cancer[3][4].
First, the high incidence of stomach cancer in the mainland
Why does stomach cancer "concentrate" in these places? We selected several representative counties and cities and found that these places have very special eating habits.
1. Zhuanghe County, Liaoning
Salted pork
Image source: Tencent Medical Code
In winter, almost every household in Zhuanghe County, Liaoning Province, marinates a jar of salted pork for a year's worth of pork supply.
Long-term consumption of salted pork, its rich large amount of salt can directly damage the gastric mucosa, causing chronic stomach disease, and ingestion of nitrite will also increase the risk of stomach cancer [5].
2. Changle County, Fujian Province
Shrimp oil, dried pickled fish, fish sauce
Changle County is a representative city with a high incidence of gastric cancer in the coast, local residents have the habit of eating shrimp oil and pickled salted fish, such pickled foods are rich in nitrites, which will increase the risk of stomach cancer, and "Chinese-style salted fish" has been identified as a class of carcinogens by the WHO.
In addition, fish sauce often consumed by locals contains a lot of salt, which can cause damage to the gastric mucosa and provide "convenient conditions" for the carcinogenic effects of nitrites and the like [6].
3. Linqu County, Shandong
Sour pancakes, pickles
In Linqu County, where sour pancakes (made from fermented grains), studies have shown that people who regularly consume sour pancakes have an increased risk of stomach cancer compared with those who do not eat them [7].
In addition, local residents prefer to eat pickled pickles, so they also consume large amounts of nitrite, which may induce stomach cancer [8].
4. Wuwei City, Gansu Province
pickles
Wuwei City is one of the high incidence areas of stomach cancer in Hexi, and local residents have the habit of eating pickled vegetables in winter, which is a substitute for winter vegetables, and can be eaten continuously for up to 2 to 4 months per year.
Studies have found that local pickles contain high amounts of nitrate and nitrite, which are closely related to the development of stomach cancer [9].
The incidence of stomach cancer in Liangzhou District of Wuwei is 3,425,400 per 100,000, far higher than the average in Gansu Province (62.37 per 100,000) [10].
5. Xining City, Qinghai
Strong tea
Qinghai Xining and the surrounding Haidong area eating habits are very special, like to eat lamb, barbecue, drink strong tea, etc., stomach cancer incidence and mortality rate for a long time ranked first in China.
Thick tea (boiling tea) is a special local drink, which is made by trampling and fermenting the stems and leaves of tea leaves, and boiled with salt before drinking.
Studies have found that drinking strong tea may be associated with stomach cancer[11][12].
6. Yancheng, Jiangsu Province
Pickles with porridge
Pickled and fermented vegetables (such as pickles such as dried radish) have always been a traditional delicacy in Yancheng and are also commonly used as a food accompaniment, and many locals like pickles with porridge.
It has been found that a high-salt diet, especially high-salt and high-heat foods, may be associated with a high incidence of local stomach cancer [13][14].
Second, the common point of the high incidence of gastric cancer
It can be seen that the diet in the high incidence of stomach cancer in mainland China almost has its "local characteristics", and their common features are:
1. Heavy taste
High concentrations of salt by stimulating the gastric mucosa, can lead to the detachment of gastric wall cells, destruction of the gastric mucosal barrier, increasing the incidence of chronic gastritis, peptic ulcer;
At the same time, it will also "amplify" the effect of carcinogens on gastric tissues, increasing the possibility of genetic mutations, thereby promoting the occurrence of gastric cancer.
2. Love pickling
Long-term, large intake of pickled foods, such as cured meats, fish and vegetables, these foods have a high nitrite content.
Although nitrites do not directly cause stomach cancer, they can react with amines or amides under acidic conditions to produce nitrosamines and nitrosamides, which are the carcinogens that really cause stomach cancer.
Amines or amides can be broken down from proteins such as fish, eggs, meat, etc. that people regularly consume.
Therefore, although a small amount of nitrate and nitrite is harmless, long-term, excessive intake will still increase the risk of stomach cancer.
In addition, more than half of the population has Helicobacter pylori in the body, and when it is present with nitrates in pickled foods, nitrates are also easily converted to nitrites, which can also promote stomach cancer.
3. Other factors
In some underdeveloped areas of the mainland, refrigerators have not yet been popularized, and the intake of fresh fruits and vegetables cannot be guaranteed; many residents have the habit of eating overnight meals, which are rich in nitrites, which can further lead to an increased risk of stomach cancer.
In addition, the high infection rate of Helicobacter pylori in some underdeveloped areas, the higher prevalence of chronic stomach disease, and the relatively slow early screening of gastric cancer may cause stomach cancer to occur "concentrated".
Although "stomach cancer on the tip of the tongue" is worrying, food and health are not indispensable.
The food mentioned above, occasionally eating once or twice when you are hungry, is understandable, but when eating for a long time and becoming a habit, you must beware of your stomach to protest.
If you live in these areas, you may really need to "change your taste".
Pay attention to eating less or no pickled foods in daily life, eating more fresh fruits and vegetables, and conducting regular screening follow-ups, all of which help to stay away from stomach cancer.
When everyone consciously does this, the hat of the "high incidence of stomach cancer" can be taken off as soon as possible.
Note: The "stomach cancer index" does not represent the carcinogenicity of food, but only the local incidence of stomach cancer as a reference.
bibliography:
[1] Chen W, Sun K, Zheng R, et al. Cancer incidence and mortality in China, 2014[J]. Chinese Journal of Cancer Research, 2018, 30(1): 1.
[2] Yang L.Incidence and mortality of gastric cancer in China[J]. World journal of gastroenterology: WJG, 2006, 12(1): 17.
Chen Wanqing, Sun Kexin, Zheng Rongshou, et al.Incidence and mortality of malignant tumors in China in 2012[J].China Oncology,2018,27(1):1-14.
Zou Wenbin, Li Zhaoshen. Research progress on incidence and mortality of gastric cancer in China[J].Chinese Journal of Practical Internal Medicine, 2014(4):408-415.
Liaoning Provincial Center for Disease Control and Prevention. Liaoning Province 2013 Annual Health and Family Planning and Population Health Status Report[M].Liaoning Science and Technology Press, 2014.
Zhou Yan, Ma Jingyu, Jiang Huijuan, et al. Incidence and mortality of malignant tumors in the tumor registration area of Fujian Province in 2014[J].China Cancer Clinical,2018,45(17):898-903.
You Weicheng. Research and intervention of gastric cancer and precancerous lesions: A practice of a high-detection field of gastric cancer in 23 years[J].Journal of Beijing University (Medical Edition) 2006, 38(6):565-570.
Fu Zhentao, Xu Aiqiang, Zhao Ying, et al. Incidence and mortality level of malignant tumors in Shandong Province in 2013[J].Chinese Journal of Cancer Prevention and Control, 2017(18):1261-1267.
Li Yumin, Chen Liren, Xue Qunji, et al. Determination of nitroso compounds in pickled vegetables in Wuwei City and analysis of the causes of high incidence of gastric cancer[J].Analytical Testing Technology and Instruments, 2003, 9(2):88-90.
Liu Yuqin, Li Wenying, Zhu Yitong, et al.Incidence and mortality of malignant tumors in tumor registration area of Gansu Province in 2013[J].Chinese Oncology, 2018, 27(4):246-255.
Ma Yingcai, Xiong Yuanzhi, Yang Weihong, et al.Relationship between Helicobacter pylori infection status and gastric mucosal pathology in the high incidence area of gastric cancer in Xining and surrounding Haidong counties in Qinghai[J].Clinical Convergence, 2004, 19(4):181-183.
Cai Chengxi, Zhao Wenqi. Analysis of the epidemic trend of gastric cancer in residents from 2009 to 2014 in Xining City, Qinghai Province[J].Chinese Journal of Cancer Prevention and Control, 2018(6).
Xu Hairong. Epidemiological study on the influencing factors of gastric cancer in areas with high and low incidence of malignant tumors in Jiangsu Province[D].Nanjing Medical University, 2007.
Han Renqiang, Wu Ming, Luo Pengfei, et al.Incidence and mortality of malignant tumors in Jiangsu Province in 2014[J].Tumor Prevention and Treatment, 2018.
*The content of this article is a popularization of health knowledge and cannot be used as a specific diagnosis and treatment recommendation, nor is it a substitute for face-to-face consultation by a practicing physician, for reference only.
*The copyright of this article belongs to Tencent Medical Code, unauthorized media reprinting is prohibited, and illegal reprinting will be investigated for legal responsibility according to law. Individuals are welcome to forward to the circle of friends.