Dietary factors: Diet is closely related to the development of gastric cancer. In recent years, the incidence of gastric cancer in developed countries in Europe and America has been decreasing, which is mainly related to dietary factors. This is mainly related to dietary factors. The characteristics are: in the past, food was preserved by smoking (smoked fish, bacon) and salt curing methods, which contain quite high carcinogens, such as benzo(a)pyrene and nitrosamines, while high concentration of salt is considered as carcinogenic substances. Food fried in high-temperature oil also contains a certain amount of polycyclic aromatic hydrocarbons carcinogens. Talcum powder is commonly used to treat rice in Japan, and talc contains carcinogenic asbestos fibers. High-salt foods such as cured meat, cured fish, cured poultry, pickled vegetables, bacon and salami are also noted because high-salt foods can damage the gastric mucosa and make carcinogens easily absorbed by the body. A survey in China’s Henan Province showed that salt consumption was significantly and positively correlated with gastric cancer mortality. The lack of protein, fat, certain vitamins and minerals in the diets of certain people makes the host nutrition unbalanced, thus reducing the body’s resistance, which directly or indirectly favors the occurrence of stomach cancer.