The evidence we have says that rBGH, or recombinant bovine growth hormone, isn't bad for you to consume. It's certainly bad for the cows, however, and it promotes bacterial resistance to antibiotics, which is bad for everyone.
rBGH is a synthetic copy of a hormone that's naturally produced by cows. When rBGH is injected into their udders, they produce more milk. Because of this, the dairy industry uses rBGH to produce more milk.
On the chemical level, rBGH probably isn’t bad for you. The growth hormone receptors in our bodies are incompatible with rBGH, and there's little chance that rBGH could reach those receptors intact in the first place. Most of the rBGH in milk is destroyed through the process of pasteurization. There's nothing right now that shows rBGH which made it through pasteurization can survive digestion intact. Nor is there evidence that the digestion process breaks rBGH down into chemical fragments that could bond with our cells and have a harmful effect.
Very young babies have guts that can sometimes absorb proteins intact. Mother's milk, however, does not contain rBGH, and most infant formulas are pasteurized at intense temperatures that would break rBGH proteins apart.
The milk of cows that are given rBGH also has higher concentrations of a protein called insulin growth factor one, or IGF-1. Normal levels of IGF-1 help certain cells in the body to grow. Too much IGF-1 has been linked by some studies to higher rates of different kinds of cancer, although the nature of the connection is still unclear.
Luckily, the IGF-1 in rBGH milk is probably not a threat to people. It's not denatured by pasteurization, but the stomach and intestine break IGF down before it can interact with our cells. Whatever small amounts of IGF-1 survive that process are a drop in the bucket compared to the amount of IGF-1 that's produced by the human body every day. Like rBGH, those small amounts might pose a threat to infants, but 90% of the IGF in formula is deactivated by the manufacturing process.
While rBGH isn't much of a threat to people, it's terrible for cows. It causes mastitis, which is a painful infection of the udder. The udder becomes inflamed and blood and pus leak into the cow's milk. rBGH treatments make cows more likely to give birth to deformed calves. It also damages their feet, leading to lameness. These negative side effects are why rBGH is forbidden in Israel, Japan, and the European Union.
To counteract the bacterial infections caused by rBGH, dairy farmers administer large doses of antibiotics. This is a serious problem - overuse of antibiotics leads to more bacteria that are resistant to antibiotics. Because only so many kinds of antibiotics are currently known, increased resistance makes bacteria more difficult to treat with antibiotics and increases the number of superbugs - bacteria that are completely resistant to treatment with the antibiotics we currently know about.
Effects in cows:
- Deformed birth
- rBGH and IGF-1 could be absorbed by the guts of infants
- Promotes antibiotic resistance
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Written by Sean McNulty | 09-11-2016
Written by Sean McNulty
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