By now, we’ve all heard a thing or two about polyglutamic acid (PGA) and its benefits for the skin. And if you’re a little bit more skincare-savvy than the average person, then you’ve probably heard people claiming that polyglutamic acid is 5 times or 10 times more hydrating than hyaluronic acid. That claim is why it took me months to write this article. Because I’ve been trying to find the origin of it! As it turns out, that’s an irrelevant comparison because polyglutamic acid is not here to replace other hydrating goodies but actually to support them with, well, a little bit more to offer. And we’re here to clear the air. Find below everything there is to know about polyglutamic acid for skin, its benefits, and how to use it in your skincare routine.
What is Polyglutamic Acid?
Polyglutamic acid is a chain of amino acids, namely glutamic acid, linked together (1). It’s used in skincare products like serums, moisturizers, and face masks primarily to hydrate the skin.
Polyglutamic acid is derived from fermented soybeans, which happens to be a traditional Japanese dish called Natto. The fermentation process produces a type of bacteria called bacillus. And polyglutamic acid is actually isolated from this bacteria and purified for use (2).
In skincare, polyglutamic acid has different names like gamma polyglutamic acid or sodium polyglutamate. Additionally, when a certain number of amino acids are chained together, they’re called peptides. That’s why polyglutamic acid is also referred to as a peptide. Similarly, because it’s usually derived from Natto, polyglutamic acid is also called natto gum.
As a substance, polyglutamic acid has a gummy, sticky feel to it with a gel-like texture. When applied, polyglutamic acid creates a film on the skin. This thin layer gives the skin a silky smooth feel. PGA has a high molecular weight compared to similar hydrating ingredients in the same category. It means that it doesn’t penetrate the skin as much. More on this in a bit.
What Are The Benefits of Polyglutamic Acid For Skin?
The most important benefit of polyglutamic acid is its ability to hydrate the skin and help it retain water. But there’s more.
1. It hydrates.
PGA is a humectant that hydrates the skin. A humectant molecule has the ability to attract water molecules from the environment and bind it to the skin. It’s what makes hydrated skin look so plump and bouncy.
2. It helps retain water.
But that’s only half of the story. The skin needs to be able to retain that water too. And polyglutamic acid helps the skin retain water. And this is all thanks to its physical properties, which is creating a thin layer on the skin to prevent water loss. In fact, because of its high molecular weight and film-forming properties, PGA is also used in wound healing (3).
3. It increases NMF.
Polyglutamic acid increases the production of natural moisturizing factors like lactic acid (4). So overall, it aids in maintaining a healthy skin barrier. In a sense, it creates an environment where the skin rehydrates itself. And this translates to longer-lasting moisture.
4. It supports hyaluronic acid.
Polylgutamic acid also protects hyaluronic acid in the skin. An enzyme called hyaluronidase causes the breakdown of hyaluronic acid in the skin. You might be familiar with this substance from dermal fillers. It’s used to dissolve hyaluronic acid fillers. By inhibiting the activity of this enzyme, PGA supports hyaluronic acid. In a sense, it’s an HA booster.
5. It improves skin elasticity.
As a result of hydration and better moisture, polyglutamic acid reduces fine lines and wrinkles and improves skin elasticity. This can count as an anti-aging benefit. When you consider the fact that PGA protects your HA, which tends to decrease with age, it can qualify as a “soft preventative”.
6. It’s soothing for the skin.
Polyglutamic acid is claimed to have anti-inflammatory effects too. Apparently, it prevents UV-induced inflammatory response and has a soothing and redness-reducing effect on the skin.
7. It rivals other humectants.
Polyglutamic acid is comparable to other hydrators like hyaluronic acid, collagen, and is suggested to be an alternative for even glycerin (5).
Polyglutamic Acid vs Hyaluronic Acid
Both PG and HA are humectants. That’s why they’re constantly compared with each other. And almost all brands that have polyglutamic acid in their products claim that PGA is 4 times more hydrating than HA.
So to better understand if polyglutamic acid is worth the hype, I skipped the middlemen and reached out to the manufacturers.
No idiot is going to go fermenting stuff and play with bacteria for years if there isn’t something there. Beauty brands, on the other hand, will tell you anything to sell you stuff.
So I reached out to BioLeaders Corporation, which is a Korea-based company specializing in biotechnology and biopharmaceuticals. They produce cosmetic raw materials with a special focus on polyglutamic acid, and some are even patented.
I briefly conversed with Jae-Chul Choi, who is the Director of Cosmetics Development. He co-authored several articles on PGA you can find on PUBMED.
BioLeaders have two different polyglutamic acid formulations called Gamma-Max and Gamma-Oligo. And yes, they do claim that it hydrates better than hyaluronic acid. Here’s how.
Polyglutamic acid has a higher molecular weight. Even though some manufacturers, including BioLeaders, use hydrolyzed polyglutamic acid for increased penetration, PGA is innately bigger in structure. So it can’t be as penetrative as hyaluronic acid.
Well, this difference leads to better water retention on PGA’s part because PGA usually stays on the surface level of the skin to create a barrier and prevent moisture loss.
Ever heard about humectants, especially hyaluronic acid, dehydrating your skin? We’re told to apply a moisturizer on top of a hyaluronic acid serum to “lock it in”, remember?
It’s because as much as HA is excellent at attracting water, it’s not a superstar when it comes to retaining water. That is not a problem for PGA. As we’ve established, it retains water.
Coming back to PGA holding X times more water than hyaluronic acid, I haven’t been able to confirm this. However, Mr. Choi was kind enough to send me their brochures, which were full of graphs confirming PGA’s superiority.
I’m not particularly great at reading graphs and numbers and making conclusions based on them. So have a look at these tables here (registration required) and do the math.
Who Should Use Polyglutamic Acid?
Anyone who’s looking for enhanced hydration should consider incorporating this ingredient into their skincare routine. It’s especially helpful if you have dry and dehydrated skin.
When your HA serum lacks efficiency, you can pair it with polyglutamic acid for better and longer moisture. Polyglutamic acid is a gentle, super replenishing skincare ingredient.
Much like other humectants, there are no side effects. So even if you have sensitive skin like me, you can benefit from PGA.
So this is how polyglutamic acid works, and how it benefits your skin. In sum, polyglutamic acid isn’t an ingredient that should replace other humectants you use in your routine. But it’s an amazing addition to any skincare routine where you need all the moisture you can get. So it is in fact a noteworthy hydration hero.
Read Next: The Best Polyglutamic Acid Products
- Ogunleye, A., Bhat, A., Irorere, V. U., Hill, D., Williams, C., & Radecka, I. (2015). Poly-γ-glutamic acid: production, properties and applications. Microbiology (Reading, England), 161(Pt 1), 1–17. https://doi.org/10.1099/mic.0.081448-0
- Zur, Nil & Goldman, D.M.. (2007). c-Poly glutamic acid: a novel peptide for skin care. Cosmet Toilet. 122. 64-72.
- Choi JC, Uyama H, Lee CH, Sung MH. Promotion Effects of Ultra-High Molecular Weight Poly-γ-Glutamic Acid on Wound Healing. J. Microbiol. Biotechnol. 2015;25:941-945. https://doi.org/10.4014/jmb.1412.12083
- Luo, Z., Guo, Y., Liu, J. et al. Microbial synthesis of poly-γ-glutamic acid: current progress, challenges, and future perspectives. Biotechnol Biofuels 9, 134 (2016). https://doi.org/10.1186/s13068-016-0537-7
- Lee, N. R., Go, T. H., Lee, S. M., Jeong, S. Y., Park, G. T., Hong, C. O., & Son, H. J. (2014). In vitro evaluation of new functional properties of poly-γ-glutamic acid produced by Bacillus subtilis D7. Saudi journal of biological sciences, 21(2), 153–158. https://doi.org/10.1016/j.sjbs.2013.09.004