Ingredient review
Polygamma-Glutamic Acid
INCI: POLYGAMMA-GLUTAMIC ACID
A standout hydrator that can hold thousands of times its weight in water, often outperforming hyaluronic acid in moisture retention.
In plain English
Polygamma-glutamic acid (often called PGA) is a natural, water-loving molecule made from fermented soybeans or other plant sources. It works like a sponge on your skin, pulling in and holding onto moisture far more effectively than many other hydrating ingredients. Because it forms a thin, flexible film, it also helps prevent water from evaporating from your skin's surface, keeping it plump and comfortable.
Review score
Safety, usefulness, and evidence
Strong fit for many routines
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- natural
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Easy yes for most routines
Polygamma-Glutamic Acid is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Polygamma-Glutamic Acid.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A naturally occurring polymer of the amino acid glutamic acid, produced by fermentation of Bacillus subtilis (a beneficial bacteria). It is a long-chain molecule that is water-soluble and biodegradable.
How it works
PGA sits on the skin's surface and forms a clear, flexible film. This film has an exceptional ability to bind water molecules—up to 5,000 times its own weight. By locking in moisture and slowing transepidermal water loss (the natural evaporation of water from your skin), it helps maintain hydration levels and supports a healthy skin barrier.
Pros
Superior moisture retention
PGA can hold up to 5,000 times its weight in water, making it one of the most effective humectants available for keeping skin hydrated.
Gentle and non-irritating
Derived from natural fermentation, it is well-tolerated by most skin types, including sensitive and reactive skin, with a very low risk of irritation.
Cons and cautions
Potential tackiness
At higher concentrations, PGA can leave a slightly sticky or tacky feel on the skin, which may not be ideal for all users or under makeup.
Less research than hyaluronic acid
While promising, PGA has fewer long-term human studies compared to hyaluronic acid, so its full range of benefits is still being explored.
Best for
- Anyone with dry or dehydrated skin looking for deep moisture
- People with sensitive skin who want a gentle, non-irritating hydrator
Use caution if
- Those who prefer extremely lightweight, water-thin textures and dislike any residual tackiness
Usage tips
Safety summary
Polygamma-glutamic acid is considered very safe for topical use. It is non-toxic, non-irritating, and non-sensitizing in cosmetic concentrations. No significant safety concerns have been reported in available research.
Research notes
Studies indicate PGA is a highly effective humectant with superior water-binding capacity compared to hyaluronic acid. Research also suggests it may support skin barrier repair and have mild anti-inflammatory properties. Most evidence comes from in vitro and small human trials; larger studies are needed to confirm long-term benefits.
Common label clues
- Typical concentration
- 0.1% to 1% in leave-on products
- Regulatory status
- Generally recognized as safe for use in cosmetics by international regulatory bodies, including the FDA and EU CosIng database.
- Common uses
- Serums, Moisturizers, Sheet masks, Eye creams
- Environmental note
- PGA is biodegradable and produced through fermentation, a relatively low-impact manufacturing process compared to synthetic alternatives.
Good to know
- PGA is often derived from fermented soybeans, making it suitable for vegan and plant-based skincare routines.
- It is sometimes listed on labels simply as 'Polyglutamic Acid' or 'γ-PGA'.
Common questions
What is Polygamma-Glutamic Acid in beauty products?
Polygamma-glutamic acid (often called PGA) is a natural, water-loving molecule made from fermented soybeans or other plant sources. It works like a sponge on your skin, pulling in and holding onto moisture far more effectively than many other hydrating ingredients. Because it forms a thin, flexible film, it also helps prevent water from evaporating from your skin's surface, keeping it plump and comfortable.
What does Polygamma-Glutamic Acid do in a beauty product?
PGA sits on the skin's surface and forms a clear, flexible film. This film has an exceptional ability to bind water molecules—up to 5,000 times its own weight. By locking in moisture and slowing transepidermal water loss (the natural evaporation of water from your skin), it helps maintain hydration levels and supports a healthy skin barrier.
Is Polygamma-Glutamic Acid safe for most people?
Polygamma-glutamic acid is considered very safe for topical use. It is non-toxic, non-irritating, and non-sensitizing in cosmetic concentrations. No significant safety concerns have been reported in available research.
Who should be careful with Polygamma-Glutamic Acid?
Those who prefer extremely lightweight, water-thin textures and dislike any residual tackiness
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.