Ingredient review
Undecyl Rhamnoside
INCI: Undecyl Rhamnoside
A mild, sugar-based cleanser that effectively removes dirt and oil while respecting the skin barrier.
In plain English
Undecyl Rhamnoside is a cleansing ingredient made from rhamnose, a natural sugar found in plants. It works by helping water mix with oil and dirt so they can be rinsed away. Because it's very gentle, it cleans without stripping your skin of its natural moisture, making it a favorite in mild, everyday cleansers.
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
Undecyl Rhamnoside 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 Undecyl Rhamnoside.
- 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 non-ionic surfactant derived from rhamnose (a plant sugar) and undecyl alcohol (a fatty alcohol from plant oils). It belongs to the alkyl polyglycoside family, known for being biodegradable and gentle.
How it works
It lowers the surface tension between water and oil, allowing impurities and excess sebum to be lifted from the skin and rinsed off. Its large sugar head group makes it less penetrating and less irritating than traditional sulfate-based cleansers.
Pros
Ultra-gentle cleansing
Its large sugar molecule sits on the skin surface without penetrating, so it cleans without disrupting the moisture barrier — ideal for reactive or compromised skin.
Eco-friendly profile
Made from renewable plant sugars and fatty alcohols, it is readily biodegradable and has a low environmental impact compared to many synthetic surfactants.
Cons and cautions
Low foam volume
It produces a light, creamy lather rather than big bubbles. If you enjoy a rich foam, you might feel it doesn't clean as thoroughly, even though it does.
Limited standalone efficacy
On its own, it may struggle to remove heavy, water-resistant makeup or sunscreen. Formulators often blend it with other mild surfactants for better performance.
Best for
- People with sensitive, dry, or eczema-prone skin
- Anyone looking for a sulfate-free, gentle daily cleanser
Use caution if
- Those who prefer a rich, foamy lather may find it too low-foam
Usage tips
Safety summary
Undecyl Rhamnoside is considered very safe for cosmetic use. It has low irritation and sensitization potential, and no significant toxicity concerns have been reported in normal use concentrations.
Research notes
Studies on alkyl polyglycosides, including undecyl rhamnoside, show they are mild to the skin and eyes, with excellent biodegradability. Most evidence comes from ingredient safety reviews and formulation studies rather than large-scale human trials.
Common label clues
- Typical concentration
- 1–10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics worldwide; listed on the EU CosIng database and generally recognized as safe by the Cosmetic Ingredient Review (CIR) panel.
- Common uses
- Cleansers, Micellar waters, Shampoos, Body washes, Facial washes
- Environmental note
- Derived from renewable plant sources and readily biodegradable, making it a more sustainable choice compared to petroleum-based surfactants.
Good to know
- It is often listed alongside other alkyl polyglycosides like coco-glucoside and decyl glucoside in 'sulfate-free' formulas.
- Despite its mildness, it is an effective emulsifier and can help stabilize oil-in-water creams and lotions.
Common questions
What is Undecyl Rhamnoside in beauty products?
Undecyl Rhamnoside is a cleansing ingredient made from rhamnose, a natural sugar found in plants. It works by helping water mix with oil and dirt so they can be rinsed away. Because it's very gentle, it cleans without stripping your skin of its natural moisture, making it a favorite in mild, everyday cleansers.
What does Undecyl Rhamnoside do in a beauty product?
It lowers the surface tension between water and oil, allowing impurities and excess sebum to be lifted from the skin and rinsed off. Its large sugar head group makes it less penetrating and less irritating than traditional sulfate-based cleansers.
Is Undecyl Rhamnoside safe for most people?
Undecyl Rhamnoside is considered very safe for cosmetic use. It has low irritation and sensitization potential, and no significant toxicity concerns have been reported in normal use concentrations.
Who should be careful with Undecyl Rhamnoside?
Those who prefer a rich, foamy lather may find it too low-foam
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.