Ingredient review
Sodium Polyglutamate Crosspolymer
INCI: SODIUM POLYGLUTAMATE CROSSPOLYMER
A gentle, biotech-derived humectant that holds onto water better than hyaluronic acid, making it a standout for dry or dehydrated skin.
In plain English
Sodium polyglutamate crosspolymer is a modern humectant made by fermenting soybeans. It works like a sponge on your skin, holding many times its weight in water. Unlike some humectants that can feel sticky or heavy, this one forms a light, flexible film that keeps moisture locked in without clogging pores. It's especially good for people who find hyaluronic acid too heavy or not hydrating enough.
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
- biotech
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Easy yes for most routines
Sodium Polyglutamate Crosspolymer 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 Sodium Polyglutamate Crosspolymer.
- 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
Sodium polyglutamate crosspolymer is a high-molecular-weight, crosslinked version of polyglutamic acid (PGA). It is produced through fermentation of soybeans, then chemically crosslinked to create a stable, film-forming polymer. This structure allows it to hold up to 4,000 times its weight in water, outperforming traditional hyaluronic acid.
How it works
When applied to the skin, the crosspolymer forms a thin, flexible film that sits on the surface. This film attracts and binds water molecules from the environment and from deeper layers of the skin, creating a reservoir of hydration. The crosslinked structure prevents the ingredient from being easily washed away, so the hydrating effect lasts longer than with non-crosslinked humectants.
Pros
Superior water retention
Holds up to 4,000 times its weight in water, significantly more than hyaluronic acid, providing deeper and longer-lasting hydration.
Gentle on sensitive skin
With very low irritation and comedogenic ratings, it's a safe choice for those prone to redness, breakouts, or allergic reactions.
Cons and cautions
Potential tackiness
In humid conditions or if too much product is applied, the film can feel slightly tacky or sticky until fully absorbed.
Surface-level action
Because of its large molecular size, it works mainly on the skin's surface rather than penetrating deeply, so it's best paired with smaller humectants.
Best for
- People with dry or dehydrated skin looking for intense, lasting moisture
- Those with sensitive or reactive skin who want a gentle humectant
- Anyone who finds hyaluronic acid serums not hydrating enough
Use caution if
- Individuals who prefer very lightweight, watery textures and dislike any film feel
Usage tips
Safety summary
Sodium polyglutamate crosspolymer is considered very safe for cosmetic use. It has low irritation and comedogenic potential, and no significant safety concerns have been reported in the available literature. As with any new ingredient, patch testing is recommended for those with extremely sensitive skin.
Research notes
Research on sodium polyglutamate crosspolymer is still emerging, but early studies and formulation data show it can hold significantly more water than hyaluronic acid and improve skin hydration and barrier function. Most evidence comes from in vitro and formulation studies rather than large-scale human trials.
Common label clues
- Typical concentration
- 0.1% to 1%
- Regulatory status
- Approved for use in cosmetics globally, including by the EU CosIng database and the US FDA as a cosmetic ingredient. No specific concentration limits are imposed.
- Common uses
- Serums, Moisturizers, Sheet masks, Eye creams
- Environmental note
- Produced via fermentation of renewable soy, and the crosspolymer is biodegradable, making it a more sustainable alternative to some synthetic humectants.
Good to know
- Sodium polyglutamate crosspolymer is vegan and derived from fermented soy, not animal sources.
- It is often used in 'clean beauty' formulations because it is biodegradable and produced via fermentation.
- On ingredient labels, it may appear simply as 'Sodium Polyglutamate' or 'Polyglutamic Acid' — the crosspolymer version is more stable.
Common questions
What is Sodium Polyglutamate Crosspolymer in beauty products?
Sodium polyglutamate crosspolymer is a modern humectant made by fermenting soybeans. It works like a sponge on your skin, holding many times its weight in water. Unlike some humectants that can feel sticky or heavy, this one forms a light, flexible film that keeps moisture locked in without clogging pores. It's especially good for people who find hyaluronic acid too heavy or not hydrating enough.
What does Sodium Polyglutamate Crosspolymer do in a beauty product?
When applied to the skin, the crosspolymer forms a thin, flexible film that sits on the surface. This film attracts and binds water molecules from the environment and from deeper layers of the skin, creating a reservoir of hydration. The crosslinked structure prevents the ingredient from being easily washed away, so the hydrating effect lasts longer than with non-crosslinked humectants.
Is Sodium Polyglutamate Crosspolymer safe for most people?
Sodium polyglutamate crosspolymer is considered very safe for cosmetic use. It has low irritation and comedogenic potential, and no significant safety concerns have been reported in the available literature. As with any new ingredient, patch testing is recommended for those with extremely sensitive skin.
Who should be careful with Sodium Polyglutamate Crosspolymer?
Individuals who prefer very lightweight, watery textures and dislike any film feel
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.