At present, cancer has become the number one cause of death for male and female residents. Statistics in 2007 show that cancer deaths accounted for 28.53% of the urban residents who died that year. The data shows that despite the improved cancer treatment, the 5-year survival rate of some major cancers has not improved significantly in the past 20 years.

　　The occurrence of cancer is closely related to diet. Studies ("Science" January 1997) have shown that 30% of cancer deaths are caused by improper diet. Excessive animal fats (mainly saturated fats) in the diet, too few vegetables and fruits, unscientific cooking methods, unreasonable eating methods, and too much food are the most important carcinogenic factors. Diet is mainly related to the occurrence of colon cancer, rectal cancer, breast cancer, prostate cancer, stomach cancer, snuff cancer, esophageal cancer, lung cancer and so on.

　　 Some of the dietary factors related to carcinogenesis have been basically confirmed at present: (Limited by research methods, for example, it is impossible to use humans to conduct cancer development experiments like animal experiments. Some carcinogenic factors also have carcinogenic effects on humans. There is no final confirmation, but their carcinogenic effects on laboratory animals have been confirmed)

　　1. Pesticide residues

　　 Common pesticides include organic phosphorus, organic Chlorine and carbamate insecticides, etc. Organochlorine pesticides mainly include DDT and HCH, which are relatively carcinogenic and have been proven to accumulate in the human body. Therefore, our country and most countries have banned its use. However, a survey shows that in 2000, the daily intake of DDT per person in our country was very small, but the intake of HCH was 3.11ug, which was an increase compared with 1990, mainly from the pollution of aquatic lindane.

　　Since the widely used organophosphorus pesticide residues in food and the environment are significantly less than organochlorine, it is less relevant to human tumors.

　　 2. Polycyclic aromatic hydrocarbons

　　The production of polycyclic aromatic hydrocarbons is mainly related to the incomplete combustion of organic matter. At present, there are more than 400 kinds of polycyclic aromatic hydrocarbon compounds found, about 20 of which have carcinogenic effects on experimental animals. Benzo (a) pyrene is the most important and common one. Benzo (a) pyrene in food mainly comes from barbecue food, food processing and packaging pollution.

　　3. Harmful metals

　　The three metal elements lead, arsenic and cadmium may have carcinogenic effects on the human body. They mainly come from air pollution, water pollution, soil pollution, food processing pollution, etc. It is the most difficult type of environmental pollutants in food. Generally, fish, seafood, aquatic products, high-fat meats, certain vegetables, food, etc. contaminated with factory wastewater, exhaust gas and waste residues.

　　4. Environmental estrogens

　　Environmental estrogens mainly include diethylstilbestrol, PCBs, dioxins and other substances. Diethylstilbestrol is one of the growth-promoting hormones commonly used in animal feed and a sex hormone. PCBs and dioxins are the most common environmental pollutants, mainly concentrated (enriched) in animal fat tissue. Therefore, you should eat less fat-rich meats, such as fatty meat, pork belly, fat lean meat, pork ribs, high-fat steak, fat duck, fat goose and so on.

　　5. Vinyl chloride

　　In daily life, vinyl chloride mainly comes from the plastic bag for packaging food-polyvinyl chloride. Polyvinyl chloride has certain toxicity because it contains unpolymerized monomers-vinyl chloride and additives. It should not be used for packaging food. The country also has regulations restricting its use, but this kind of plastic packaging food is still widely used in farmers'' markets. In comparison, polyethylene is safe and non-toxic, and can be used to package food. At present, this kind of plastic packaging food is used in larger supermarkets. It is characterized by a wax-like luster on the surface, a smooth and slightly hard feeling when touched by hand, and a loud noise when rubbed hard.

　　6. Nitrate and nitrite

　　Nitrate and nitrite as a coloring agent, often added to the meat in the form of mixed salt In the category of products, such as various ham sausages, luncheon meat. Nitrite can be used to synthesize N-nitroso compounds in food or stomach, most (80%) N-nitroso compounds, such as nitrosamines, are relatively clear carcinogens.

In addition to meat products, pickled vegetables (such as sauerkraut) and stale vegetables are also important sources of nitrite.

　　 In addition, some processed foods, such as smoked fish, cured meat, soy sauce, beer, fried bacon, etc., contain more N-nitroso compounds.

　　The study found that ingesting vitamins C, E and fresh vegetables and fruits, garlic, onions, tea, kiwi juice, lemon juice, etc. can block the synthesis of the carcinogen N-nitroso compounds.

　　7. Synthetic pigments

　　Many synthetic pigments are synthesized from coal tar or aromatic hydrocarbon compounds such as benzene, toluene and naphthalene, and most of them are synthesized. Harmful, all countries place strict restrictions on it. The synthetic pigments currently allowed in my country are mainly amaranth, lemon yellow, and indigo. In view of the possible carcinogenic effects of synthetic pigments on the human body, they should be used sparingly or not.

　　8. Hanging white block

　　The chemical name of hanging white block is sodium formaldehyde sulfoxylate, which belongs to industrial bleach and is not allowed to use Food additives. But some lawbreakers added it to processed foods such as yuba and rice noodles. The hanging block has been listed as a possible carcinogen by the National Cancer Research Institute (IARC).

　　9. Sudan red

　　 Sudan red is a chemical stain and is not a permitted food additive. But many businesses use it for foods that need red, such as red heart duck eggs, chili sauce, condiments, pickles, and spicy instant noodles. After the "Red Heart Duck Egg" incident exposed in 2005, the use of Sudan Red in food has been banned. Sudan red is also a possible carcinogen identified by the IARC.

　　10. Malachite green

　　 malachite green is a green crystal with metallic luster, easily soluble in water, the solution is blue-green, Has a very good sterilization effect. Some unscrupulous traders abuse malachite green to disinfect fish ponds, carriages or containers for transporting fish, etc., to prevent fungal infections caused by the shedding of fish scales. It has caused the "famous" incident of exceeding the standard of the drug residue of Duo Baoyu.

　　11. Aflatoxin

　　Aflatoxin is a metabolite of Aspergillus flavus and Aspergillus parasite, is one of the strongest carcinogens, can cause Liver cancer, esophageal cancer, etc. Aspergillus flavus mainly contaminates peanuts, corn, peanut oil, rice, etc. When buying and storing food, peanuts, soybeans and other foods, care must be taken to avoid mold. When buying peanut oil, choose products that are reliable and free of aflatoxin.

　　12. Heterocyclic amine

　　heterocyclic amine compounds have strong carcinogenicity and gene mutation. They are mainly produced by cooking protein-rich fish and meat at high temperatures. Grilled, fried fish or meat contains more heterocyclic amines. Generally, the higher the heating temperature, the longer the time, and the lower the water content, the more heterocyclic amines are produced. Therefore, to eat less, it is best not to eat grilled, fried fish or meat.

　　13. Acrylamide

　　Starch foods are prone to produce acrylamide when cooked at high temperature (>120℃). Animal test results show that acrylamide is a possible carcinogen. According to the Announcement No. 4 issued by the Ministry of Health in 2005, fried foods such as French fries, potato chips, instant noodles, fritters, and baked goods such as instant coffee and breakfast cereals all contain more acrylamide. Therefore, as far as possible, steaming, boiling and other methods should not be used to cook starch foods, and change the eating habits of fried and high-fat foods.

　　14. High-salt diet

　　Epidemiological survey found that high salt intake can increase the risk of stomach cancer. Table salt itself is not a carcinogen, but a high-salt diet can cause damage to the protective layer of the gastric mucosa, causing chronic inflammation and precancerous lesions, and does not promote Helicobacter pylori infection. Controlling salt intake in the diet can help prevent stomach cancer.

　　15. High protein diet

　　Some population surveys and animal experiment studies show that excessive intake of animal protein can significantly increase breast cancer, colon cancer, The risk of rectal cancer, pancreatic cancer, endometrial cancer, and prostate cancer. However, only "red meat", namely beef, pork, lamb and their products, have obvious effects, while "white meat" such as fish, chicken, and duck are not of such danger. Therefore, the intake of red meat should be limited. Investigations show that processed meat products have a stronger effect on cancer risk than meat raw materials.

　　16. High-fat diet

　　 It is generally believed that fat, especially saturated fat from meat is the main dietary risk factor for cancer, and breast cancer, Colon cancer is closely related. Controlling fat intake, especially fat from red meat, plays an important role in reducing the risk of cancer.

　　 17. Drinking

　　 Long-term drinking may be an important cause of esophageal cancer and cardia cancer. It is generally believed that alcohol consumption is closely related to tumorigenesis in eight sites, namely tongue cancer, oral cancer, throat cancer, esophageal cancer, gastric cancer, pancreatic cancer, lung cancer and kidney cancer. Some studies have pointed out that there is a synergistic effect between drinking and smoking.

　　18. I like hot food

　　Some bad eating habits, such as eating hot (hot) food often, eating too fast, etc. Damages the esophageal mucosa, produces chronic inflammation, and increases the risk of esophageal and gastric cancer.