rBST free or hormone free milk is what stores like Quality Dairy and Meijer are marketing to customers. It's a statewide trend that grocery retailers started jumping on about two months ago.

"It's basically just following a market trend," says Quality Dairy's Quality Control Manager, Gordon Smith. "A lot of the whole market is starting to get away from rBST, and we just want to make our consumers know that's what we're doing also.

While it's being sold and labeled as hormone free, in actuality rBST is still found in the milk of cows that are not treated with the hormone. That's because rBST is a natural hormone found in cows.

"It's a protein that's produced by the cow that affects [its'] mammary glands in such a way to increase milk production," says David Beede, Professor of Dairy Nutrition and Management at Michigan State University.

Hormone treated cows are given a synthetic version of rBST every fourteen days during their lactation cycle. It's technology approved by the Food and Drug Administration.

"Scientific studies, between the hormone treated cows' milk and non-hormone treated cows' milk, show absolutely no difference in the hormone level in the milk, in the nutritional value of the milk, and the safety of the milk," explains Sparrow Hospital's Chief Clinical Dietitian, Diane Fischer.

"It limits the purchasing choices that consumers have," Beede adds, "and by not allowing rBST milk, or milk from rBST treated cows, to be part of the choices on the dairy display, then they're able to raise the price of the quote "organic" or as they will call it hormone free milk."

Regardless if a cow is treated or not, rBST will always be a component of milk. Look at the fine print on Quality Dairy's signs, and you'll see for yourself. The signs read, "No significant difference has been shown between milk derived from rBST treated and non rBST treated cows."