Info on Milk from Wikipedia:
Milk that has not received a fat content reduction is rich in saturated fat and cholesterol, which numerous sources have suggested as contributing to an increased risk of atherosclerosis and coronary heart disease. Low-fat and non-fat forms of milk may mitigate this risk[citation needed].
Cow milk allergy (CMA) is as an immunologically mediated adverse reaction to one or more cow’s milk proteins. Rarely it is severe enough to cause death.
Milk contains varying levels of white blood cells, depending upon the health of the source animals; controversy surrounds whether these are simply somatic cells or, in an alternate form, pus [8]. In the United States, one to seven drops of these cells are in every eight-ounce glass of milk, varying by state, according to guidelines set up by the Food and Drug Administration and statistics reported by the dairy industry [9]. Only one state out of all fifty, Hawaii, has a cell count lower than the dairy industry’s recommendations; seventeen states produce milk that would be illegal to sell based on somatic cell limits in Europe.
Since November 1993, with FDA approval, Monsanto has been selling recombinant bovine somatotropin (rbST)–or rBGH–to dairy farmers. Bovine growth hormone is administered to cattle in order to increase their milk production, though the hormone also naturally fosters liver production of insulin-like growth factor 1 (IGF1). The deposit, thereof, in the milk of rBGH-affected cattle has been the source of concern, however all milk contains IGF1. The IGF1 in milk from rBGH-affected cattle does not vary from the range normally found in a non-supplemented cow. Elevated levels of IGF1 in human blood has been linked to increased rates of breast, colon, and prostate cancer by stimulating their growth [10] [11], though this has not been linked to milk consumption. The EU has recommended against Monsanto milk.[12]
In addition, the cows frequently contract an udder infection known as mastitis, partly responsible for the aforementioned prevalence of blood cells in dairy products [13]. Milk from rBGH-affected cattle is banned in Canada, Australia, New Zealand, and Japan due to the mastitis problems.
On June 9, 2006 the largest milk processor in the world and the two largest supermarkets in the United States–Dean Foods, Wal-Mart, and Kroger–announced that they are “on a nationwide search for rBGH-free milk [1].”
Several sources suggest a correlation between high calcium intake (2000 mg per day, or twice the US recommended daily allowance, equivalent to six or more glasses of milk per day) and prostate cancer [14]. A large study specifically implicates dairy [15]. A review published by the World Cancer Research Fund and the American Institute for Cancer Research states that at least eleven human population studies have linked dairy product consumption and prostate cancer.[citation needed]