Recent studies have found that feeding rats with whey protein-containing whey is a transparent liquid and soy protein precipitated in yoghurt, which can reduce the induction ratio of chemical carcinogens to breast cancer. After chemical carcinogen treatment, 100% of rats that did not eat whey protein feed and soy protein feed had tumors, whereas the incidence of tumors in the soy protein feed group was 77%, and only 54% in the whey feed group. In the cancer-bearing rats, the whey protein and soy protein groups had fewer tumors and smaller volumes than the control group. This shows that whey protein and soy protein have a significant role in the prevention of breast cancer.
Foods rich in whey protein are milk, yogurt, and whey powder. Soy protein-rich foods are various kinds of soy products, including tofu, soy milk, and soy milk.