Nowadays, people pay a lot of attention to health, we all know that eating original food is one of the ways to maintain health, drinking original self-grinding soya bean milk is the preferred method of health for many women. But “women who drink soy milk all year round will lead to breast cancer” has been circulating in the community and on the Internet, so many women are daunted. In fact, there is no scientific basis for the claim that “soy milk containing estrogen will lead to breast cancer”, mainly because of people’s “estrogenophobia”. In fact, there are many kinds of estrogens, such as animal estrogens, phytoestrogens and synthetic estrogens, as well as organic environmental pollutants that have estrogen-like effects, among which phytoestrogens are beneficial to the human body. Soy milk fritters have long been sung into popular songs, and tofu brain, tempeh, dried beans, soy skin, etc. are all common delicacies in our daily life. Epidemiological studies have long proven that the lower incidence and mortality rates of breast and prostate cancer in China and other Asian countries compared to Westerners are related to the specific dietary habits of Asians due to their high intake of soy and soy products, while the diets of Europe and the United States generally do not contain soy and soy products and have a low intake of soy isoflavones in their diets. Regular consumption of soy and soy products is the main reason for the low incidence of breast cancer among residents of Asian countries. A study of 5,042 women aged 20-75 years with breast cancer in Shanghai found that eating soy products significantly reduced the recurrence and mortality rates of breast cancer patients, and the results of this study were published in 2009 in the prestigious American medical journal JAMA. The results of a case-control study of Chinese women living in Singapore on diet and breast cancer also suggest that soy has a significant preventive effect on breast cancer development. In an epidemiological study of soy isoflavone intake and breast cancer risk among women in Takayama, Japan, Professor Wada et al. found that women with higher intakes of soy and soy products had a relatively lower risk of developing breast cancer before menopause, and that An important article published in 2008 in the British Journal of Cancer also concluded that isoflavones in soy not only do not increase the risk of breast cancer, but also reduce it, especially in soy-based foods Asian populations with higher consumption of soy foods. Although some pure soy isoflavones have been found to promote tumor growth in some in vitro cell lines and animal studies. However, there is no direct relationship to suggest that soy causes cancer. This is because there is a wide variety of phytoestrogenic isoflavones in soy, and as monomers, it is normal for them to exhibit partial stimulation and partial inhibition of cancer cells. Moreover, humans and animals differ in the effects of isoflavones, and the effects of dietary soy and experimental isoflavones are equally different. In addition to counteracting the excess of harmful estrogens in the body, phytoestrogens also have a substitution effect when the human physiological estrogens are insufficient, which is called the “two-way regulation” of estrogenic effects, ensuring that the body avoids harmful stimuli and ensures normal physiology. Recent studies have shown that this bidirectional balancing effect of soy isoflavones on estrogen can significantly affect estrogen-related tumorigenesis. When genistein (a component of soy isoflavones) and estrogen act simultaneously on target organs in vivo, the two can competitively bind estrogen receptors in the body, thereby significantly reducing the incidence of estrogen-associated tumors. And when estrogen levels in the body are too high, soy isoflavones exhibit an anti-estrogenic effect. In addition to preventing breast cancer, soy can also alleviate female menopausal syndrome, prevent osteoporosis and cardiovascular disease. Therefore, the statement that “women who drink soy milk all year round will cause breast cancer” is not scientific. We advocate the long-term and moderate consumption of soy foods or crude products, which can effectively prevent the occurrence of breast cancer and cardiovascular diseases.