There are three main types of whey protein powder – whey protein concentrate, whey protein isolate, and whey protein hydrolysate.

All three types come from cow’s milk, and all three types undergo the processing described above with just slight variations.

Whey protein concentrates undergo the least amount of processing, exactly as described in the previous section. This whey protein still contains some natural sugars, in the form of lactose, and some fat.

Whey protein isolates go through additional processing to remove most of the lactose and fat, leaving mostly protein behind.  

Some companies use heat, acid, enzymes, or a combination of techniques to break down the protein bonds in whey protein to make the protein easier to absorb.  This easier-to-absorb protein is referred to as whey protein hydrolysate.  Whey is already easy to absorb to begin with, yet this small tweak usually comes with a hefty price tag.

To examine the relationship between acne and whey protein, it’s helpful to start with the link between dairy and acne.

Several studies have shown dairy can increase a hormone called insulin like growth factor 1 (IGF-1).  It’s clear that high levels of IGF-1 from dairy products can negatively impact our skin in several ways.

IGF-1 increases sebum production.  Sebum is the oil on the skin that can lead to blocked pores and acne if produced in excess.

IGF-1 can also increase inflammatory markers, and inflammation is a driving factor for acne.

Research even shows high levels of IGF-1 is linked to worse post-acne scarring. 

Another way dairy could be linked to acne is its effect on insulin.  

Research shows milk-derived proteins promote insulin production, and too much insulin over time can lead to insulin resistance.

Insulin resistance is linked to a lot of different hormonal imbalances including Polycystic Ovarian Syndrome (PCOS), all of which can contribute to acne.

Whey protein comes directly from milk, so it’s safe to assume whey protein could increase IGF-1 and insulin levels just like milk.

Pregnant Cows Year-Round

In the US, farmers keep cows pregnant so they can maximize the amount of milk they produce.  

Free-range cows in other countries get pregnant naturally and are typically milked for five or six months after they give birth.

Meanwhile, in the US we get cows pregnant artificially so they have one calf a year.  This means they can produce milk for about ten months every single year.

Because US cows are pregnant 75% of the time (cows are pregnant for 9 months just like humans), their hormone levels are high the majority of the time too.  

For example, milk from pregnant cows contains up to 500 times more estrogen as the cow gets close to giving birth!

ARE HUMANS AFFECTED BY HORMONES IN MILK?

These high levels of hormones in milk appear to affect us when we drink it.

A 2010 research study  looked at various hormone levels in men, women, and children after consuming milk.

The men drank milk and then did blood tests to look at how their hormone levels responded.

The children drank milk and then collective urine samples to see how their hormone levels were affected.

Women were told to drink two cups of milk a day for 21 days, and markers of ovulation were tracked to see if the milk would affect their ovulation timing.

In men, estrogen and progesterone levels significantly increased, peaking around 30-60 minutes after drinking the milk.  They also saw decreases in testosterone around 2 hours after milk consumption.

In children, they saw an increase in hormones, peaking 1-3 hours after they drank the milk.

In women, only one of the five women experienced a change in ovulation timing. 

But keep in mind, that doesn’t mean the milk wasn’t impacting their hormones.  Ovulation timing is just one marker of hormone balance.  And we might have seen changes in ovulation timing if the women had continued to drink two cups of milk per day.  

The milk changed hormone levels for the men and kids, so it was probably changing the women’s hormone levels too.

With that being said, it’s important to pay attention to research studies to keep things in perspective. 

A closer look at the research methods shows the men drank a lot of milk – four to five cups based on their body weight.  The children drank quite a bit as well – two to three cups, also based on their weight.

So would one whey protein shake a day affect your hormone levels?

Maybe.

If you’re having trouble with your hormones or hormonal acne, does it make sense to cut it out for a period of time to see if it helps?  I would argue a big fat yes.