Experts and BHG readers answer.
I often see, “rBST-free” written on milk cartons. What is rBST and why is it important?
Recombinant bovine somatotropin—also known as rBST—is a hormone that causes dairy cows to produce greater quantities of milk. Although it mimics a hormone that is naturally regulated in a cow’s pituitary gland, its use is controversial.
Those who oppose its use cite studies linking rBST consumption in milk to premature puberty in girls, a higher incidence of twin births, and elevated occurrences of cancer in humans. Many in the dairy industry repudiate these claims.