Ingredient review
Undecylenoyl Glycine
INCI: UNDECYLENOYL GLYCINE
A gentle, amino-acid-based ingredient that helps control oil and support a balanced skin microbiome without stripping the skin.
In plain English
Undecylenoyl glycine is a mild, soap-like molecule made from an amino acid (glycine) and a fatty acid from castor oil. It helps cleanse the skin gently while also reducing the activity of certain acne-causing bacteria and calming oil production. Unlike harsh detergents, it works with your skin's natural chemistry to keep the barrier healthy.
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
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Easy yes for most routines
Undecylenoyl Glycine 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 Undecylenoyl Glycine.
- 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
Undecylenoyl glycine is a semi-synthetic compound created by combining glycine (an amino acid) with undecylenic acid (a fatty acid derived from castor oil). It is often used in skincare as a mild surfactant and antimicrobial agent.
How it works
It acts as a gentle surfactant, helping to lift dirt and oil from the skin without stripping its natural moisture barrier. Additionally, it has been shown to inhibit the growth of Cutibacterium acnes (the bacteria linked to acne) and to reduce sebum production by modulating androgen receptors in the skin.
Pros
Gentle on skin
Unlike many surfactants, undecylenoyl glycine cleanses without stripping the skin's natural oils, making it suitable for sensitive or acne-prone skin.
Oil-regulating
It helps reduce sebum production, which can lead to fewer breakouts and less shine over time.
Cons and cautions
Moderate evidence
While promising, the research on undecylenoyl glycine is still limited compared to more established acne-fighting ingredients like salicylic acid or benzoyl peroxide.
Not a standalone cure
For moderate to severe acne, it is best used as part of a broader treatment plan rather than as a sole active ingredient.
Best for
- People with oily or combination skin
- Those with mild acne looking for a gentle alternative to harsh actives
Use caution if
- Individuals with known allergies to castor oil derivatives
- Those with very dry or compromised skin barriers (use with caution)
Usage tips
Safety summary
Undecylenoyl glycine is considered safe for cosmetic use at typical concentrations. It has low irritation and comedogenic potential, making it suitable for most skin types. As with any ingredient, patch test if you have sensitive skin or known allergies.
Research notes
Studies indicate that undecylenoyl glycine can reduce sebum production and inhibit acne-causing bacteria. However, most research is industry-funded and more independent clinical trials are needed to confirm its efficacy compared to standard treatments.
Common label clues
- Typical concentration
- 0.1% to 2%
- Regulatory status
- Approved as a cosmetic ingredient in the EU, US, and other major markets. Not classified as a drug.
- Common uses
- Cleansers, Toners, Serums, Moisturizers
- Environmental note
- Derived from castor oil, a renewable plant source, but the synthesis process involves chemical modification.
Good to know
- Undecylenoyl glycine is often listed as a key ingredient in 'microbiome-friendly' or 'sebum-regulating' products.
- It is considered a milder alternative to salicylic acid for those with sensitive skin.
Common questions
What is Undecylenoyl Glycine in beauty products?
Undecylenoyl glycine is a mild, soap-like molecule made from an amino acid (glycine) and a fatty acid from castor oil. It helps cleanse the skin gently while also reducing the activity of certain acne-causing bacteria and calming oil production. Unlike harsh detergents, it works with your skin's natural chemistry to keep the barrier healthy.
What does Undecylenoyl Glycine do in a beauty product?
It acts as a gentle surfactant, helping to lift dirt and oil from the skin without stripping its natural moisture barrier. Additionally, it has been shown to inhibit the growth of Cutibacterium acnes (the bacteria linked to acne) and to reduce sebum production by modulating androgen receptors in the skin.
Is Undecylenoyl Glycine safe for most people?
Undecylenoyl glycine is considered safe for cosmetic use at typical concentrations. It has low irritation and comedogenic potential, making it suitable for most skin types. As with any ingredient, patch test if you have sensitive skin or known allergies.
Who should be careful with Undecylenoyl Glycine?
Individuals with known allergies to castor oil derivatives Those with very dry or compromised skin barriers (use with caution)
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.