The causes of breast cancer are not yet fully understood, but it is worth noting the risk factors that trigger breast cancer: Family history of hereditary breast cancer can take two forms: one is that the mother has breast cancer, and the daughter also has breast cancer, which occurs at a young age, often before menopause, and is mostly bilateral; the other is that the mother has not had breast cancer, but in a family, at least two sisters have breast cancer. The incidence of breast cancer in this kind of family is 2-3 times higher than that in families without family history. Menstrual factors: If the age of menarche is earlier than 12 years old, the risk of breast cancer is 2 or 2 times greater than that of menarche at 17 years old; if menopause is later than 50 years old, the risk of breast cancer increases about 1 times than that of menopausal patients after 45 years old. Too many miscarriages: Normal natural miscarriages do not increase the risk of breast cancer, but repeated abortions or multiple abortions before the age of 18 are likely to cause breast diseases and increase the risk of breast cancer. Breastfeeding: Breastfeeding is one of the best natural means to prevent breast cancer, and breastfeeding can reduce the risk of breast cancer by 20% to 30%. Poor quality of sex life: Breast disease and sex life are closely related, and sexual repression in women can increase the incidence of lobular hyperplasia and breast tumors. Domestic surveys show that 86% of women with lobular hyperplasia have never reached orgasm during sex; the older the age of first marriage, the higher the incidence of breast cancer. Depression: Among single women, ladies left behind, PR girls, retired female workers and some secondary school teachers, more suffer from breast diseases and the incidence of breast cancer is also high. As these women are prone to depression, such as nervousness and anxiety, loneliness and depression, sadness and sorrow, bitterness and disappointment, impatience and irritation, the body’s life rhythm will be disturbed and the neuroendocrine system will be dysfunctional, which will lead to the imbalance of the internal environment and the decrease of immunity, which will reduce the production and release of thymosin from the thymus gland and the monitoring ability and phagocytosis of lymphocytes and macrophages on mutated cells in the body. The ability of lymphocytes and macrophages to monitor and phagocytose mutated cells in the body is reduced, and cancer is likely to occur. Obesity is closely related to breast cancer. Girls who are obese are prone to early sexual maturity, which will lay the foundation for breast cancer in the future. The incidence of breast cancer in obese people is 3 or 45 times higher than that of non-obese people, because excess fat accumulation increases the production of estrogen, and excess estrogen is lipidated and stored in the fatty tissue and continuously released into the bloodstream, which stimulates the breast tissue and, over time, easily causes breast cancer. In addition, most obese people have hypercholesterolemia and hyperinsulinemia. When the cholesterol in the body is elevated, the cholesterol content in the cell membranes of lymphocytes and macrophages increases, which inhibits the immune function. Bad habits: smoking and alcoholism as “fashionable”, going to nightclubs and dance halls, staying up all night in the midst of the glamour, eating fried food and all kinds of sweets and pastries, but never eat rough food and vegetables; celibacy, or getting married and having children after 30 years old, and not wanting to breastfeed after having children, etc.