Washington’s dairy farm families are committed to producing wholesome, nutritious and safe dairy products. We are equally committed to animal welfare, environmental stewardship and the communities we serve. Because we want you to be confident in the dairy products you eat and drink, we want you to know about rbST—what it is; what research has shown about using rbST; and, ultimately, why Washington milk is rbST-free.
What is rbST?
rbST, or recombinant bovine somatotropin, is a form of bovine somatotropin or bST—a protein hormone produced naturally in the pituitary glands of all cows. In fact, all mammals produce this kind of protein hormone in some form—including humans. There are two types of hormones: steroid and protein. rbST is not a steroid hormone; it’s a protein hormone—meaning it is digested just like any other protein when it’s consumed.
rbST enables cows to produce 10% to 15% more milk. Strictly as an example, that means one cow can produce enough in a day to provide milk for 125 school lunches. The same cow supplemented with rbST can provide enough milk for about 145 school lunches.
Multiple, exhaustive studies have been conducted on the safety and effectiveness of rbST by the Food and Drug Administration, the World Health Organization (WHO) and the Food and Agricultural Organization (FAO) of the United Nations (UN)—among many other respected scientific and public health authorities. All of these organizations have deemed the products from cows given rbST safe for human consumption, safe for the cow and safe for the environment. The FDA approved the use of rbST in U.S. dairy cattle in 1993; and to date, there is no FDA-approved test that can tell the difference between milk from cows given rbST and cows not given rbST. That's because there is no difference: no test can distinguish between two things that are the same.
The lock and the key
One of the purposes of bST and rbST is to stimulate growth in a calf that drinks its mother's milk. In fact, all mammalian species—including humans—pass growth hormone to their young in this manner. But that doesn't mean that a glass of milk will make you grow an inch before sun-up. All growth hormones are species-specific—in other words, they only work on their own kind. Bovine somatotropin is composed of a chain of amino acids that has only 30% of its sequence in common with the amino acid chain forming human somatotropin (or hST, which stimulates growth in people). When rbST passes over growth receptors in the human body, it cannot be recognized—and it produces no growth effect. The system works like a lock and a key: if you don't have the right key, you cannot open the lock.
Washington milk is rbST-free
There are some states and countries that do administer rbST to their dairy cattle, but you can rest assured that Washington milk is rbST-free. And while some dairy products are labeled rbST-free, that does not mean that those packaged without rbST-free labeling were produced from cows supplemented with rbST. All Washington dairy processors have banned the use of rbST by the dairies that ship them milk, so all Washington-produced milk is rbST-free—whether or not you see it on the package.
Did You Know? There is a tracking number on your milk, so you can see that it was produced from rbST-free Washington dairy cows: find out where your milk is from.
Drink with confidence
Our cows are well cared for with properly balanced diets for every stage of life to give you safe, nutritious milk. You can drink Washington milk with confidence. Studies show rbST is safe for human consumption; but we wanted to leave no doubt, so we took it out.