It’s pretty common that whenever I’m discussing our food system that hormones are brought up. I’ve heard about the horrors of hormones. I’ve heard stories about hormones present in beef. The rumors regarding larger chicken breasts being due to the injection of hormones. Also, of course the whole ‘hormones in milk’ thing is typically thrown in. All of these assumptions are usually associated with earlier puberty in some form or fashion during the duration of the conversation. I promise that we’ll get to discussing hormones in beef and hormones in chicken (even though I can guarantee you there’s nothing to worry about there). But today, I wanted to share with you the secret behind hormones in milk – specifically rBST in milk.

The Secret Behind rBST in Milk

Ready? The secret is that all milk has hormones in it. In fact, everything you consume has hormones in it (except for salt). That’s because hormones are simply proteins. Any and all food that you’ve consumed that was ever living have them present.

Typically when people hear the word hormones they start to remember conversations about growing up and developing. After all, you probably remember a whole host of things being blamed on them when you were in that angsty stage. But if you remember biology basics, you’ll realize that while hormones are associated with reproductive systems they mostly serve as messengers. They are sent to specific locations to coordinate everything from growing tissue to producing adrenaline in fight or flight situations.

During the majority of the time when people refer to concern about hormones in the food that they eat they are referring to added hormones, or hormones that are not there naturally.

Naturally Occurring Hormones in Milk

We’ve established that all food that was ever sourced from a living being has hormones present. So what’s all the fuss?

Many have been concerned about the hormone that milk naturally contains known as BGH (Bovine Growth Hormone) or BST (Bovine Somatotropin). Naturally occurring BGH/BST have a similar function in a cow’s body just like the hormones our bodies produce do. They encourage cell growth and come from the pituitary gland. Cows milk also includes 1GF-1 (insulin like growth factor 1) that we will discuss later in this blog post.

Synthetic Hormones in Milk

Some farmers, only about 17% in the United States (per 2007 survey data) utilize rBST (recombinant Bovine Somatotropin) or rBGH (recombinant Bovine Growth Hormone). This is created in a lab. However, it is processed by the cow’s body just as the naturally produced version is. They have chosen to utilize this tool because it can stimulate a cow’s milk production and ultimately produce more with less resources. With this being said many consumers are concerned about the potential for rBST in milk.

Does Milk From Cows Treated with rBST Have a Direct Negative Effect On Me?

rBST/BST Doesn’t Work In the Human Body

I think at this point it is important to mention that while tons of people are concerned about the naturally produced version of rBST in milk that both are tailored to work in a cow’s body. Not a humans. Our bodies don’t process this hormone in the same way that their bodies do. They just treat it as a protein, meaning it is broken down in our digestive tract.

No Significant Difference

Even if it did, there is no significant difference in the amount of rBST/BST present in a glass of milk produced from either cow. That’s right – you could be paying a premium for a product that is for all intensive purposes the same nutritionally. In fact we’re talking a few nanograms difference per milliliter of rBST in milk. To put this into perspective for you if you were to break a paperclip (that weighs a gram) and break it into a million pieces, each of these would represent a nanogram. So the difference is pretty negligible.

Most rBST/BST Is Never Absorbed

It’s also important to note that if you are drinking milk which is pasteurized (treated with heat to destroy any harmful microbes) that this decreases any remaining BST in milk by 85% to 90%. All milk is going to be pasteurized unless you are purchasing raw milk directly from a dairy farmer.

Does Consuming Milk from Cows Treated With rBST Have Any Indirect Negative Effects Upon Me?

So we’ve talked about BST/BGH or it’s artificial forms rBGH/rBST in milk, but we know that for most things any human or animal consumes they are rarely independent in how they can react. There has been a lot of concern regarding if consuming milk will increase your chances of getting cancer. This is because when cows are treated with rBST/rBGH this affects another naturally occurring hormone in milk – IGF-1.

What is 1GF-1?

IGF-1 is also known as an insulin-like growth factor 1. It is produced naturally in response to BGH/rBST/rBGH by the liver. We talked about how BGH doesn’t affect humans, it is the same with IGF-1 produced by cows influenced by BGH/rBSH/ rBST in milk. The IGF-1 in cows is however identical to what we produce in our own bodies.

1GF-1 In Our Bodies

We do produce our own insulin-like growth factor naturally in our own saliva and even our digestive tract! The levels we produce regularly present in our blood are significantly more than what we could ever consume in milk.  Even drinking it regularly in large amounts.  Mothers also produce 1GF-1 in their breast milk and the levels of 1GF-1 in bovine milk are even less than this!

Does Milk Cause Cancer?

The reason that many are concerned about 1GF-1 is because many have impression that is can cause cancer. Cancer, like any disease, is caused by several different factors. Some studies have found a “correlation,” showing that milk can have an impact upon developing certain types of cancers. But a correlation does not mean a cause.  Drinking a glass of milk  once a day is not going to give you cancer. In fact if you were to look at all of the data, it doesn’t have a significant impact one way or the other. Things like smoking, any gene mutations you’re born with, obesity etc. can definitely have a negative impact on your health.

Have any other questions about BST/rBST/rBGH in milk? If I can’t answer them I promise to find someone who can! If you liked this you’ll probably enjoy learning more about where milk comes from , nitrites in meat, if it’s humane to eat meat, labels on beef, finding a prime steak and whats really in your hot dog!

Thanks for reading!

Lauren