One study is not powerful enough to definitively say if something increases or decreases cancer risk. There is a good article on Vox about this, with the following graphic: Looking at the data here for milk, whey has no effect on cancer risk, maybe a small protective effect at best. read more
Years ago, I learned from Dr. T. Colin Campbell’s book, written with his son, Dr. Thomas Campbell, The China Study, that casein has the ability to turn on and turn off cancer growth simply by adjusting the level of intake of that protein. read more