1.Smokers: long-term smokers are prone to lung, larynx, nasopharynx, stomach, bladder and kidney cancers; 2.Obesity: obese people are more prone to colon, cervical and breast cancers than the general population; 3.Bad dietary habits: frequent high-fat diet, too fine food, little vegetables and fruits, or love and love to eat pickled foods, smoked foods, overly hot and hot foods, impermeable pickled vegetables, etc. are prone to Bowel cancer, esophageal cancer, oral cancer, liver cancer; 4. Hepatitis B patients: more prone to liver cancer than the general population; 5. Gastric ulcer and chronic gastritis and cancer-causing chemical contact: more prone to stomach cancer; 6. Long-term contact with certain cancer-causing chemicals: such as long-term contact with coal tar, soot and paraffin, mineral oil, asbestos, arsenic, insecticide, chromium, chromium salt and nickel, etc.; 7. Long-term contact with Those who are in close contact with radioactive substances: mainly those who are in close contact with X-rays, radioactive isotopes, etc., and who do not do enough personal protection are prone to leukemia; 8. Those with family history of certain cancers: some cancers have certain genetic tendency, such as retinal cell cancer, breast cancer, gastrointestinal cancer and esophageal cancer, etc. Family members who have blood relationship with these cancers should be more alert to cancer; 10.