Whey Protein: A Scoopful Of Acne?

By Seppo | Cause

Big muscles are built with whey protein powders. But can we also say the same about big pimples? Can whey protein cause acne?

Anecdotal evidence is all over the map, as usual. Some say whey protein causes breakouts, while others claim no effect. In this post we’ll see what the science has to say about this. We’ll start by quickly reviewing the hormonal factors behind acne and how milk and whey affects them. Then we’ll look at studies on how protein powders affect these hormones.

The short answer is yes, whey protein can cause acne. Because the same hormones that stimulate muscle growth also stimulate sebum production and skin cell growth.

[social_quote duplicate=”no” align=”default”]Going to the gym? That whey protein shake can give you acne.[/social_quote]

How whey protein could cause acne

Let’s start with a brief look at how whey could cause acne. It comes down to a hormone known as insulin like growth factor 1 (IGF-1). IGF-1 is a growth hormone and thought to accelerate muscle growth, unfortunately it also accelerates acne.

  • Studies have found a correlation between IGF-1 and sebum levels, so the higher the IGF-1 levels the more sebum the skin produces.
  • IGF-1 reduces transcription factor FOXO1 in the skin cells. Acne-prone skin is already deficient in FOXO1, which is linked to all the major factors behind acne (androgen sensitivity, sebum production, excess skin cell growth, too much keratin). So this moves the needle to the wrong direction.

To put it shortly, IGF-1 puts hormonal acne into overdrive.

You know it’s bad when…

Nestle has a keen interest on this topic. Smart people as they are, they figured that if their products give people acne sales are likely to drop. So in a paper published in Nestle Nutrition Workshop Series they concluded with this.

The elimination of the whey protein-based insulinotropic mechanisms of milk will be the most important future challenge for nutrition research.

Melnik BC.
Evidence for acne-promoting effects of milk and other insulinotropic dairy products.
Nestle Nutr Workshop Ser Pediatr Program. 2011;67:131-45. Epub 2011 Feb 16.

In the paper they reviewed the ways milk aggravates acne and placed a special emphasis on insulin (and IGF-1) spiking effects of whey. The paper recommended that Nestle research ways to eliminate the insulin spiking effect of milk, because: “When the insulinemic index of milk has been adjusted to a level corresponding only to its carbohydrate moiety, we will look again into acne-free faces of less obese young people.” So cute.

There you have it, straight from the horse’s mouth, whey aggravates acne. This is already pretty damning evidence, but doesn’t directly address the use of whey protein powders.

Studies on the effect of whey protein on IGF-1 levels

[social_quote duplicate=”no” align=”default”]Did you know? The same hormones that stimulate muscle growth can also cause acne?[/social_quote]

Research on protein powders has focused more on the effect on muscle growth and strength, understandably. Unfortunately, that leaves us with only a handful of relevant studies to look at.

  • One study put 19 untrained males into 10 week resistance training program. One group got protein supplement (PRO) with 20g of protein (14g whey and casein and 6g of free amino acids. The other group got a placebo supplement that contained 20g of dextrose (CHO). After 10 weeks the PRO group showed higher IGF-1 levels.
  • This was confirmed by another study that found combined protein and carbohydrate supplement (42g PRO, 24g of CHO and 2g of FAT) increased IGF-1 levels more than 70g carbohydrate only (CHO) supplement. The supplement was taken twice a day. The study went on for 6 months and the IGF-1 graph shows the difference increased over time. Estimating from the graph IGF-1 levels were up by about 20% at the 6-month mark, compared to slight decline in the CHO group. The study didn’t specify the type of protein used, other than that it was Myoplex.
  • Finally, we have this short-term study on experienced bodybuilders. The study just looked a single bout of 2-hour weight training session, and found no effect on IGF-1 levels with any supplement (PRO, CHO or CHO/PRO). Given that these are experienced bodybuilders they’ve probably already ‘maxed’ out their IGF-1 and thus the supplement showed no effect.

Those are the only studies that compare protein supplements to other supplements. Protein powders, in general, increase IGF-1 levels more than carbohydrate supplements. This is good for muscle growth but bad for acne.

There was also one study on postmenopausal women. Not exactly the best match when we talk about bodybuilders, but I’ll mention it because it eliminates the effect of resistance training as confounding variable. Those who took 30g of whey protein per day had 8% higher IGF-1 levels than those taking a placebo with identical caloric content.

Protein powders and mass building supplements in general

Quite a few studies looked at protein powders and mass building supplements in general. Usually they are a combination protein and carbohydrates and vitamins, free amino acids are sometimes added. These shakes are usually pretty heavy, and the caloric load alone is enough to spike insulin and IGF-1 levels. That’s why they are not relevant if we want to focus on whey protein.

But they are relevant if you want to know whether protein powders and mass building shakes in general can cause acne. Taking supplements increases IGF-1 and insulin levels after exercise more than exercise alone. Long-term, these supplements also increase baseline IGF-1 levels. Both of these effects are bad for acne, but good for muscle growth.

Adding branched chain amino acids (BCAA) to the supplements makes them even worse for your skin. That’s because BCAA (and especially leucine) activates the mTor pathway, which is sort of a mastermind protein behind acne.

What about soy protein

Several studies have compared whey, casein and soy protein on muscle growth and strength, but none that I saw mentioned IGF-1 levels. Whey protein might stimulate muscle growth a bit better, but in the big picture the differences are quite small.

Soy protein has been studied in non-bodybuilding population, and it’s been shown to increase IGF-1 levels in both young and old men and in postmenopausal women.

So given all that we’ve covered so far I think it’s safe to say soy protein has similar effect on IGF-1 levels (and acne) than the other types of protein powders. It might be a bit better choice for acne-prone bodybuilders than whey protein, but whether that makes any practical differences, I can’t say. On the other hand, if you look at the comments below you’ll see several people commenting that their skin got a lot better after they switched from whey to soy protein.

Not a problem for everybody

We can say that whey protein increases the risk of getting acne, but it’s obviously not going to give acne to everybody.

IGF-1/insulin pathway is just one way to get acne. For some people acne is more inflammatory and more tied to gut issues and food sensitivities. For these people whey protein may not cause any problems.

Here’s a (not comprehensive) checklist of things that put you into high-risk group as far as whey and other protein powders are concerned:

  • You have oily skin. This means you either already have elevated insulin and IGF-1 levels or that your skin is very sensitive to these hormones.
  • You are insulin resistant with elevated post-meal and fasting blood sugar levels.
  • Your acne is aggravated by eating sugar and simple carbohydrates.

And keep in mind that you are not powerless in this struggle, see the oily skin remedies post for more.


Studies consistently show that protein powders work. They stimulate muscle growth and strength more than weight training alone. But this boost comes with a cost. Protein powders increase IGF-1 and insulin levels, both of which are linked to hormonal acne. Protein-rich supplements lead to higher increase than pure carbohydrate powders.

While there are no formal studies on whey protein on acne, it’s highly likely they cause acne at least to some people. Things that put you into high-risk group are: oily skin, insulin resistance, and acne that is aggravated by sugar and simple carbohydrates.

Unfortunately skin’s sensitivity to androgens and IGF-1 is determined by genetics, so there’s no simple way to fix this. Topical remedies can, to some degree, reduce sensitivity and mitigate the problem. But increasing muscle growth with protein powders and clear skin are inherently opposing goals, both depend on the same hormones.

So what do you think? Are protein powders worth the increased risk of acne? Or do you have your own story to tell?


About the Author

Seppo Puusa, a.k.a. AcneEinstein shares rational advice about natural and alternative acne treatments. Read more about me and my acne struggles at the page.

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