While we can't imagine ever parting with our hyaluronic acid serums and creams, every now and then, a new, buzzy ingredient will come along to remind us that perhaps HA isn't the be-all and end-all of skin hydrators. Case in point: polyglutamic acid (PGA), a water-soluble peptide that's quickly shaking up the beauty industry. Research on naturally occurring poly-γ-glutamic acid (γ-PGA) - a molecule found in the bacteria of fermented soybeans - suggests it has the ability to hold more moisture than hyaluronic acid. Like four to five times more.
"Polyglutamic acid is an excellent humectant, similar to hyaluronic acid," says Dr. Monica Li,"In the lab, polyglutamic acid, as a gel, has been found to be able to absorb moisture up to 5,000 times its own weight," says Dr. Li. "But the actual water amount retained depends on the acidity, or pH, and salt content of the gel." By comparison, hyaluronic acid holds up to 1,000 times its weight in water.
However, Dr. Li suggests that the two ingredients need not be seen as competitors. In fact, when used together, they could actually end up being the ultimate recipe for hydrated skin. "Polyglutamic acid may inhibit hyaluronidase, which breaks down hyaluronic acid," explains Dr. Li. PGA also essentially creates a seal that keeps moisture from escaping. It could be quite "complementary to hyaluronic acid, which is found in the deeper skin layers," says Dr. Li.
While hyaluronic acid works within the skin to increase moisture levels deep down, polyglutamic acid can actually increase the production of natural moisturizing factors on the skin's surface to improve hydration, too, she adds. "It has also been shown to help maintain elasticity of the skin."
It has the potential to be a major game-changer when it comes to hydrating, plumping skincare. Below are some products that contain polyglutamic acid.
