While you can be confident that all milk produced in the U.S is pure and safe, some milks are labeled "hormone-free", which raises the question — are there hormones in milk?
Here are the plain facts: all living things — both plant and animal foods as well as the human body — have hormones. Dairy cows naturally produce a growth hormone called “bovine somatotropin”, which aids milk production. Some farmers supplement this with a safe, synthetic hormone called rBST. Nearly 90 percent of these hormones are destroyed during pasteurization and remaining trace amounts are broken down by the body during digestion. Both hormones are species-specific, meaning they have no effect on the human body. And after years of rBST use, no clear link has been shown to exist between the consumption of dairy foods, including milk, to health concerns such as early puberty or breast cancer. Backed by scientific testing, leading health organizations including the Food and Drug Administration, The National Institutes of Health, World Health Organization, and American Medical Association, all support the view that milk from rBST-treated cows is safe.
Bottom line: You can enjoy dairy milk in any form knowing that it is among the most highly regulated and safest foods available. Or if you prefer, organic or other forms of hormone-free milk are widely available.