Causes of breast cancer: 1, family history 2, the chances of breast cancer in women with young age at menarche; 3, the chances of breast cancer in women with late menopause; 4, the chances of breast cancer in women with short menstrual cycle; 5, the chances of breast cancer in women with old age at the first full-term gestation; 6, the chances of breast cancer in women with high number of births; 7, the chances of breast cancer in women who are not breastfeeding; 8, the chances of breast cancer in middle-aged women who consume too much High-fat and high-calorie foods are prone to breast cancer; 9. Alcohol consumption can increase the incidence of breast cancer; 10. Increasing the fiber content of food can reduce the incidence of breast cancer; 11. Vitamins can reduce the incidence of breast cancer; 12. Ionizing radiation can increase the incidence of breast cancer; 13. Physical exercise can reduce the incidence of breast cancer; 14. The incidence of breast cancer in special occupations and high-risk occupations is increased: e.g. beauty industry, pharmaceutical industry. Special occupations and high-risk occupations have higher incidence rates of breast cancer, such as beauty industry and pharmaceutical industry; 15. The incidence rate of breast cancer on one side of the patient’s opposite side of the breast is higher than normal; 16. Obesity is related to the incidence of breast cancer.