There’s a lot of talk these days about the use of antibiotics and growth hormones in our milk, and a lot of misinformation going around. So let’s settle the debate.
Are hormones being used to increase milk production in the US? Yes, and this has been going on for quite some time now (since 1993 actually). Specifically, in 1993 the FDA approved the use of recombinant (artificial) bovine growth hormone (bST, or sometribove zinc) in cattle feed to increase milk production. Now, that might sound worrisome but there’s a reason why the FDA approved it. That’s because this hormone is destroyed by our digestive system, and even if it did, it does not affect humans at all because it’s not recognized well by the receptors on our cells.
Now unfortunately, using bST in cattle feed to increase milk production also has the effect of increasing the risk of bacterial infections in the udder. This can cause inflammation of the udder, a condition coined “mastitis”, which can be fatal. Since the cause is primarily bacterial, farmers therefore have started adding antibiotics to their feed to prevent infection. Again, this has worried a lot of people, but it really shouldn’t. See, the FDA has been measuring the presence of antibiotics in samples from both milk tankers and milk itself. Turns out that antibiotics have only been detected in at most, 0.1% of samples from tankers and 0.01% of actual milk samples since 1994. Furthermore, these numbers have decreased over the time period of measurement.
So at the end of the day, there is absolutely no reason why you should worry about the presence of antibiotics and bST in the milk you drink. In fact, the FDA even found that adding these to cattle feed doesn’t even have much effect on the molecular composition of the milk. Despite that fact, it remains unknown if bST and antibiotics nonetheless alter the taste profile of the milk. Personally, I think bST-free milk actually tastes better…at least compared to the store brand available in my area!