Composition of milk, rbST or not, is the same


GREENFIELD, Ind. — A panel of physicians, nutritionists, and animal scientists has completed a review of the research relevant to recombinant bovine somatotropin (rbST) and found no link to human health risks from drinking milk.

RbST is the supplement approved by the U.S. Food and Drug Administration (FDA) for increasing milk production in lactating dairy cows. It is marketed by Elanco, a division of Eli Lilly and Company.

Led by Richard Raymond, M.D., former undersecretary for Food Safety at the USDA and former chief medical officer of Nebraska who is now an executive consultant with Eli Lilly/Elanco, the panel addressed questions and concerns on rbST pertaining to general biology, human health and animal health, nutritional content, environmental impact and milk quality.

The panel (scroll down for a complete list of panel members and their affiliations) concluded that “contrary to some claims, there is no scientific link between drinking milk from cows supplemented with rbST and any human health issues, including the decline in age of puberty and the risk of breast cancer,” Raymond said.

Continued controversy

The product has not been without controversy, however, as major retailers have required suppliers to provide milk only from cows not supplemented with rbST, and several states, including Ohio, are grappling with labeling issues related to rbST milk.

Milk marketers, including Dairy Farmers of America and its Dairy Marketing Services, are requiring that all DFA milk that goes to Class I plants must be from nonrbST-treated cows. Dairymen must sign an affidavit verifying that fact to ship milk to fluid milk plants.

The paper is the first review and compilation of scientific data since the initial documentation was provided to the FDA in support of the approval of rbST. The paper was presented at the 2009 Joint Meeting of American Dairy Science Association, Canadian Society of Animal Science and American Society of Animal Science in Montreal, Canada.

Breast cancer myth

“One of the myths about rbST percolating in the public is that drinking milk from rbST-supplemented cows causes breast cancer,” said David Clemmons, M.D., Sarah Graham Kenan Professor of Medicine and Biochemistry at the University of North Carolina at Chapel Hill.

“This is false as the evidence does not support any cause and effect, and the actual rate of breast cancer in women in the United States has been declining in recent years.

“In fact, in 75 percent of women who are diagnosed with breast cancer, there are no known risk factors other than age and living in Western society.”

Milk is milk

BST, by nature, is a major regulator of milk production in lactating dairy cows. The panel found that milk from rbST-supplemented cows is indistinguishable from organic or rbST-free milk.

“In fact,” said Ronald Kleinman, M.D., Charles Wilder Professor of Pediatrics at the Harvard Medical School, “conventional milk has the same levels of hormones and nutrient composition as milk labeled as rbST-free or organic.”

Posilac, the brand name for the rbST product, received U.S. Food and Drug Administration approval in 1993.

Global nod

Regulatory authorities in 56 countries, including Australia, Canada, European Union member states, South Korea and the United States, have determined that milk and meat products from cows supplemented with rbST are safe for consumption by people of all ages.

In addition, scientific bodies such as the World Health Organization (WHO), the Food and Agricultural Organization of the United Nations (FAO) and the National Institutes of Health (NIH) have reached the same conclusions.

According to Elanco, no major global dairy market restricts the import of dairy products from rbST-supplemented cows.

Members of the rbST panel

Richard Raymond, M.D., former undersecretary for Food Safety at the USDA, and current consultant to Eli Lilly/Elanco

Connie W. Bales, Ph.D., R.D., associate research professor in the Department of Medicine at Duke University Medical Center

Dale Bauman, Ph.D., Liberty Hyde Bailey Professor in the Department of Animal Science and the Division of Nutritional Sciences at Cornell University

David Clemmons, M.D., professor of Medicine and Biochemistry at the University of North Carolina

Ronald Kleinman, M.D., Charles Wilder Professor of Pediatrics at the Harvard Medical School

— Dante Lanna, Ph.D., professor of Biotechnology and Animal Metabolism at University of Sao Paulo

Stephen Nickerson, Ph.D., professor of Lactation Physiology at the University of Georgia

Kristen Sejrsen, Ph.D., associate professor at Aarhus University, College of Agricultural Sciences

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  1. Artificial Growth Hormones may not cause breast cancer but those of us whose breast cancer tumors are estrogen receptive positive better stop eating any dairy products that come from cows treated with rBST or rBGH.
    I actually experienced my own little research project. Many years ago when this topic was brought up I stopped buying milk that came from cows treated with the artificial growth hormones. I never even thought about all of the other dairy products. My breast cancer metastisised to my bones and I have been on AIs(anti estrogen drugs)and chemo. My tumor markers were just going up and up and then about 4 months ago I figured out that I had been eating ice cream almost on a daily basis that came from cows given growth hormones and hadn’t paid attention to any of the other dairy proucts like yogurt, butter, cheese and sour cream.
    When I eliminated every dairy product that did not plainly state on the container that it came from cows not treated with rBST or rBGH, my tumor markers went down 15 points the first month and have continued to go down every month since.


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