rBST – harmless hormone or frankenfood?

Submitted by sproutingforth on Tue, 2007-03-27 11:06

rBST or recombinant bovine somatotropin - also known as bST, bGH, rbGH, and Monsanto’s brand name for the hormone, Posilac - is “a naturally-occurring protein produced by all dairy cows and a necessary component of milk production”, or so the opening lines on Monsanto’s website go [monsanto dairy]

What they’re not including in their information is that rBST is a controversial, genetically engineered version of this growth hormone, used for increasing milk production in cows – by between 5-15%. And that the increased milk output translates to an average increase in net profit for dairies of $100 a year per cow.

It has been banned for use in the EU, Japan, Canada, Australia, New Zealand and all but 19, mostly non-industrialised countries (read: South Africa) - mainly due to consumer demand - and has been linked to increasing rates of breast and prostate cancer, precocious puberty and obesity.

There are a number of regulatory, academic and scientific bodies – WHO, FDA and the European Commission Directorate for Consumer Health among them – who have found milk from rBST-supplemented cows to be safe for humans, and that there is no difference between milk from cows that do or don’t receive these supplements.

Monsanto repeatedly claims that 'the amounts are too small and digestion too complete for them (growth hormones) to have any direct effect in humans.'

But then Monsanto is the only company approved by the FDA (food & drug administration) to manufacture and sell rBST within the US. The hormone was approved by the FDA in 1993 – 14 years ago.

Let’s take a look at the health of cows, for a start:

• rBST has been associated with increased risk of mastitis in cows
• it substantially increases foot problems (lameness) & injection site reactions
• it can also cause reproductive disorders [wikipedia]

In other words, the welfare and health of the average dairy cow is worse off for the hormone and treated cows are at a higher risk of being culled.

So does rBST affect our health?

Monsanto’s studies show that using rBST in cows increases insulin growth factor 1 (IGF-1) in milk. Some studies have revealed that IGF-1 levels in the human blood stream are higher in patients with breast, prostate or colorectal cancer. [milk & cancer connection]

In May last year, the Scientific American reported that Dr Gary Steinman of the Long Island Jewish Medical Centre published a paper in the Journal of Reproductive Medicine proposing a link between IGF and the incidence of twin births. He draws attention to the increased rate of twins in both USA and the UK – over the last 30 years, the number of twin births has nearly trebled – and it isn’t because of in vitro fertilization! [sciam.com]

Then there’s the unpublished rat study Monsanto supplied to the FDA for drug approval. Monsanto claimed no rats absorbed rBST in their blood stream so there was no need for long term toxicity studies. But Canadian scientists who obtained the study discovered that 20% - 30% of the rats did absorb rBST with biggest concentrations in the prostate. There were also thyroid cysts. (Capital Times Dec 18, 1998) [online journal]

Demand for organic milk (produced without the use of synthetic hormones) has increased 500% in the US. In fact, it is the fastest growing sector of the organic food market.

In other words, the controversy about rBST's health effects are enough to affect consumer demand. At the time of writing this article, we don’t know what the statistics in SA are for the use of rBST hormone - suffice to say that both Woolworths and Pick ‘n Pay produce rBST-free dairy products - due to consumer demand.

Read some more about rBST on urban sprout here

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