Skincare

Polyglutamic Acid

Effective dose
0.1–2 %
Evidence
2/5· Emerging

Last updated June 1, 2026

What it is

Polyglutamic acid (gamma-PGA) is a large amino-acid-based humectant biopolymer that binds water and forms a thin moisture-trapping film on the skin surface. It is marketed as holding more water than hyaluronic acid and may support natural moisturizing factors and reduce water loss. It is used in serums and moisturizers at low concentrations.

Benefits

May boost surface hydration and reduce transepidermal water loss; typical use is roughly 0.1-2%, but human clinical evidence specific to topical polyglutamic acid is still limited and mostly preliminary.

When to take it

Use AM or PM on damp skin and follow with a moisturizer to lock in water; it layers well over watery serums and under heavier creams. It offers no sun protection, so use sunscreen during the day.

Side effects

Generally well tolerated as a surface humectant, with low irritation potential; allergic reactions are uncommon. As with any humectant, very dry low-humidity environments can blunt its benefit unless sealed with a moisturizer.

Sources

Products containing Polyglutamic Acid

No products in our database contain this ingredient yet.