By Alex Avery

The research facts and scientific evidence was already clear; but a new puberty study from the University of Michigan C.S. Mott Children’s Hospital reinforces what medical experts already know about early puberty in children – that it simply cannot be caused by things like bovine growth hormones (bST/bGH) found naturally in milk or influenced in any way when cows get supplemental bST, but this rare condition is linked to kids’ size, more specifically their body mass index or BMI. Obesity, not milk, is linked to precocious or early onset of puberty.

In the March issue of the journal Pediatrics, the researchers reveal that a higher body mass index (BMI) score in girls as young as age 3, and large increases in BMI between 3 years of age and first grade are associated with earlier puberty, defined as the presence of breast development by age 9. This longitudinal study is unique in that it included girls younger than age 5 to examine the association between weight status and timing of puberty.

“Our finding that increased body fatness is associated with the earlier onset of puberty provides additional evidence that growing rates of obesity among children in this country may be contributing to the trend of early maturation in girls,” says lead author and U-M pediatric endocrinologist Joyce Lee, M.D, MPH.

Studies have suggested that girls in the United States are entering puberty at younger ages today than they were 30 years ago, says Lee. Since rates of childhood obesity also have significantly increased during the same time period, researchers have speculated that childhood obesity may be contributing to a trend of earlier puberty in girls.

Researchers from groups like the National Research Center for Women & Families and other academic experts have published extensively on this subject; however, activist groups like The Organic Consumers Association and the natural product marketing groups which fund them continue to make claims linking early puberty to milk and bovine growth hormone continue while the experts clearly call them “untrue.” The Washington Post and New York Times have reported extensively on the safety of rBST. In an October 2003 article on the alleged milk link to early puberty published by the Washington Post exposed the flaws “with the rBGH and early puberty theory: Children today drink markedly less milk than they did a generation or two ago. According to the U.S. Department of Agriculture (USDA), milk consumption among girls ages 6 to 11 dropped by about one-third from the late 1970s to the late 1990s.

“Not only is there no evidence” that rBGH affects human growth, says Paul Kaplowitz, the new chief of endocrinology at Children’s National Medical Center and a specialist in the issue of early puberty, “it’s not even scientifically possible.” Kaplowitz, who subscribes to the increased body fat theory, has little patience for those who blame hormone-treated cow’s milk. “I’m really at a loss as to where this connection comes from,” he says. “People are always eager to find environmental culprits for early puberty. It’s a very emotional thing with a lot of people.” 

There is really no evidence to support the advocacy claims about milk and puberty — claims often used by dairy marketers seeking to scare consumers into buying higher priced organic or organic-lite milk. Extensive research and basic medical science show milk and bovine growth hormones are safe and they simply cannot cause early puberty.

More support for what I have been saying all along. Milk is milk. Enjoy.

This entry was posted on Monday, March 5th, 2007 at 4:34 pm and is filed under Uncategorized . You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.