Not Clearly Pro or Con to the question "Is Drinking Milk Healthy for Humans?"
"One reason milk consumption may lead to cancer risk is insulin-like growth factor, IGF-1 (not to be confused with bovine growth hormone, rBGH). Milk contains IGF-1 for good reason: milk is designed for babies, and IGF-1 helps us grow. IGF-1 affects growth, as well as other functions, and is normally found in our blood. Higher levels of IGF-1, however, appear to stimulate cancer cells."
"Hormones in Milk Are Linked to Cancer," Consumer Health Journal, Mar. 2004