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I consume high quantities of whole milk (probably a third-gallon a day), and I'm concerned with the potentially negative cancer-causing effects of this consumption.
I found the following claims on this website:
Researchers are looking, not only at whether milk increases cancer risk, but how. The answer, apparently, is in the way milk affects a man's hormones. Dairy products boost the amount of insulin-like growth factor (IGF-I) in the blood. In turn, IGF-I promotes cancer cell growth.3-5 A small amount is normally in the bloodstream, but several recent studies have linked increased IGF-I levels to prostate cancer and possibly to breast cancer as well.
Milk does other mischief. Its load of calcium depletes the body's vitamin D, which, in turn, may add to cancer risk. Most dairy products are also high in fat, which affects the activity of sex hormones that play a major role in cancer.
What does the research suggest is the case?