I heard that soy foods contain estrogen and have a promoting effect on breast cancer, is this really true? Actually, this is not the case. On the contrary, soy contains hydroxyisoflavones, a phytoestrogen-like substance that not only does not have estrogenic activity, but also can competitively bind estrogen receptors, thus preventing the binding and activation of estrogen receptors and their ligands; at the same time, isoflavones can also prevent the nutrient absorption of cancer cells, which can have a preventive effect on breast cancer. Scientists in the United States and Asia have found that isoflavones are a unique cancer-preventing substance in soy foods, which can effectively inhibit the occurrence of colon cancer, lung cancer, liver cancer and esophageal cancer, in addition to breast cancer prevention. It has also been found that exogenous lectin proteins contained in fava beans and peas can stop the value-added of heterogeneous cells, thus preventing the growth of tumor cells.