title: Soybean diet lowers breast tumor incidence in irradiated rats.
abstract: This paper examines the relationship between feeding a diet rich in protease inhibitors and the reduction of mammary cancer induced by x-irradiation in Sprague-Dawley rats. Of a total of 145 irradiated animals, 44% of the 45 rats fed a raw soybean diet containing a high concentration of protease inhibitor developed mammary tumors as compared to 74% of 50 rats fed a casein diet containing no protease inhibitor. Animals fed Purina rat chow which contained low levels of protease inhibitor exhibited a 70% mammary tumor incidence. No spontaneous neoplasms were found in any of the non-irradiated animals on the raw soybean diet whereas about 10% of the animals on the protease-free diet developed tumors. Thus, soybeans which are rich in protease inhibitors reduced the induction of mammary cancer in x-irradiated rats. This work suggests that diets rich in protease inhibitors may contribute to reducing cancer incidence in man.
mesh_terms: D000818:Animals; D001835:Body Weight; D002364:Caseins / Q000494:pharmacology; D004032:Diet; D004041:Dietary Fats / Q000494:pharmacology; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000517:prevention & control*; D011480:Protease Inhibitors / Q000494:pharmacology*; D051381:Rats; D013025:Glycine max; D014361:Trypsin Inhibitors / Q000494:pharmacology; D014965:X-Rays
chemical_list: D002364:Caseins; D004041:Dietary Fats; D011480:Protease Inhibitors; D014361:Trypsin Inhibitors