Milk is a white, nutrient-rich liquid food produced in the mammary glands of mammals. It is the primary source of nutrition for infant mammals (including humans who are breastfed) before they are able to digest other types of food.Despite the hype, cow's milk actually robs our bones of calcium. ... So every glass of milk we drink leaches calcium from our bones. That's why medical study after medical study has found that people who consume the most cow's milk have significantly higher fracture rates than those who drink little to no milk. Drinking lots of milk could be bad for your health, a new study reports.Women who drank three glasses of milk or more every day had a nearly doubled risk of death and cardiovascular disease, and a 44 percent increased risk of cancer compared to women who drank less than one glass per day, the researchers found