Monsanto recently issued a press release announcing they are divesting of the rBST product. Monsanto states they are not removing the product from the market, but rather looking to offload the business to a different company. In this first of several posts on rBST, I’ll try to provide some scientific background.

rBST or recombinant bovine somatotropin is a synthetically produced hormone that is identical to a hormone produced in the pituitary gland of cattle. In cattle, BST is present in milk at about 10 parts per billion, whether they receive rBST or not. BST is broken down by the digestive tract when milk is consumed. Even when injected directly into pituitary glands in humans, the BST hormone has no effect (this was tried when BST was first discovered, thinking it might be a way to treat growth hormone deficiency in humans).

The FDA’s review of the product, including levels of IGF-1 and BST in the milk concluded that rBST was safe and that milk from rBST-treated cows was indistinguishable from non-treated animals. Much of the original data submitted to the FDA has been subsequently validated in other research.

The recent JADA paper we discussed here also found no biologically meaningful differences in rBST-free, traditional and organic milk. In fact, the few statistical differences were often in a direction counter to what opponents of rBST would have us believe.

A study at Cornell University concluded that the use of rBST reduced the carbon footprint of milk production. It does this through increasing the efficiency with which cows convert feed to milk. Less feed per gallon = less poop, less greenhouse gas and less cows needed per gallon.

Given all the “rBST-free” labels appearing on the shelves though, there is obviously some controversy here: Wikipedia presents a reasonable summary of the rBST issues. The use of rBST does increase mastitis (inflammation of the udder), although this is similar to what is seen in high-producing dairy cows that are not treated with rBST. So, the question is more of how high the production rate is, than of rBST.

Scientifically, I don’t believe there is any food safety reason to base your milk choices on rBST status of the cows that produce it.

1. suzannabanana23 Says:
   August 12th, 2008 at 2:18pm

   Sara — I am really confused by all this. Of course, no one wants to feed their kids milk that might have extra unnecessary stuff in it. But I understand rBST is just the same hormone that makes cows lactate naturally. So, for example, if my milk wasn’t coming in for my own baby and there was some shot I could get to make it come in, I might get something similar. Is this in the ballpark of true?

   And, in further clueless mom fashion, I just want to say this. I SPEND FIFTEEN DOLLARS A DAY ON MILK!!!!! Serious business, we drink THREE GALLONS A DAY of milk!!! And my boys are not even teenagers yet. Do the math — that’s $450/month ON MILK!!!! (MORE, hello, than I spend on GAS for my car.)

   So — if rBST is just a natural hormone, if it increases milk production and supply, doesn’t it stand to reason that it’s a good thing?

   And remember — I am foodie, organic gardening mom. But with grocery bills on the upswing, triple the amount of money as usual going into my gas tank, do I really need to spend more that $15/day on milk??



2. Sara Says:
   August 13th, 2008 at 5:15pm

   Suzanna–you are begging the topic of my next post, which is waiting some confirmation from people who know more than I do.

   rBST is given to cows part way through their natural lactation cycle to delay the tailing off in production typically seen after a few weeks. So, if the cow doesn’t have milk to begin with, it won’t help. It does, however keep the cow milking at her highest level for longer.

   Monsanto and many supporters claim that this product is important in keeping the cost of our milk low. I’m all for people being able to make choices (which usually come at a higher price), but I wonder if ethically “we” (the vocal) have the right to demand a product be removed from production if it keeps costs down, with implications for those who can’t afford to choose.



3. User links about "monsanto" on iLinkShare Says:
   March 13th, 2009 at 12:03am

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