Old Wives' Tales
Radio & TV
Toxin du jour
Claim: Milk sold at Wal-Mart contains rBST, a dangerous growth hormone.
Origins: rBST, or recombinant bovine somatotropin, is an artificial growth hormone injected into dairy cows approximately every two weeks to boost milk production. It is the synthetic
The use of rBST is controversial. On the plus side, it elevates milk production and boosts farm income. On the downside, it can increase udder infections in cows (thereby necessitating greater use of antibiotics), and some say it may increase cancer risk in milk drinkers.
The cancer claims have not been proved. Those who say there is a risk point to a connection between rBST injections and elevation of another hormone in cows,
Use of rBST is banned in Canada, but not because of any potential ill effect it might have on humans; its use was proscribed because of its harmful effects on cows (udder irritation).
The Food and Drug Administration (FDA) says rBST is safe for consumers and that milk from rBST-treated cows is no different from milk from non-treated cows:
Before the 1993 approval of rbST, FDA determined that the recombinant, or genetically engineered form of bST is virtually identical to a cow's natural somatotropin, a hormone produced in the pituitary gland that stimulates the production of milk. During that rbST approval process, FDA concluded that there is no significant difference between milk from treated and untreated cows. For that reason, FDA also concluded it does not have the authority to require special labeling for milk and dairy products from rbST-treated cows, and that producers have no basis for claiming that milk from cows not treated with rbST is safer than milk from rbST-treated cows.Assurances notwithstanding, recent years have seen a grassroots consumers movement away from products reliant upon antibiotics or growth hormones. Shoppers are increasingly seeking out "rBST- (or rBGH-)free" milk in lieu of the hormone-assisted sort. But it comes at a price — this type of milk is far more expensive. While a half-gallon of 2% milk (Lucerne) goes for $1.99, its
We encountered this e-mail purporting to detail a teen's reaction to the rBST in the milk she drank in March 2007. While there is reason to believe the young woman depicted in the tale exists and that the description of her travails is at least somewhat accurate, that's a far cry from saying her drinking of rBST-enhanced milk caused her medical woes. There have been rumors that rBST causes premature puberty in children, but as yet there's nothing credible to hang them upon. Indeed, arguing against such an outcome is the type of hormone itself: Somatotropins (growth hormones) are not the same as gonadotropins (sexual development hormones), and they don't cross functions, especially when applied to different species.
The e-mailed alert includes an exhortation to swear off milk from
On 21 March 2008, Wal-Mart announced that its "Great Value" milk would no longer be sourced from rBST-enhanced cows.
Barbara "milk dud" Mikkelson
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