Ingredient review
Potassium Lauroyl Hydrolyzed Soy Protein
INCI: Potassium Lauroyl Hydrolyzed Soy Protein
A mild, amino-acid-based surfactant that cleanses without stripping the skin, making it ideal for sensitive or dry skin types.
In plain English
This ingredient is a gentle cleanser made by combining lauric acid (from coconut or palm oil) with hydrolyzed soy protein. It works like a mild soap that removes dirt and oil without leaving your skin feeling tight or dry. Because it's derived from natural sources and is very gentle, it's often used in products for sensitive skin.
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
Potassium Lauroyl Hydrolyzed Soy Protein 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 Potassium Lauroyl Hydrolyzed Soy Protein.
- 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 semi-synthetic surfactant created by reacting lauric acid with hydrolyzed soy protein. It belongs to the family of amino-acid-based cleansers, known for their mildness and compatibility with skin.
How it works
It lowers the surface tension between water and oil, allowing dirt and sebum to be rinsed away. Unlike harsher sulfates, it has a larger molecular structure that doesn't penetrate the skin barrier, so it cleanses without causing irritation or excessive dryness.
Pros
Extremely gentle on skin
Its large molecular structure means it cleanses without penetrating or disrupting the skin barrier, reducing the risk of irritation and dryness.
Conditioning effect
Unlike many cleansers that can leave skin feeling tight, this ingredient leaves a soft, smooth feel because the soy protein provides light conditioning.
Cons and cautions
Lower foam volume
It produces a creamy, low-lather foam that some users accustomed to high-foaming cleansers may find less satisfying.
Potential allergen concern
Although highly processed, the soy protein source may be a concern for those with severe soy allergies, though reactions are extremely rare in cosmetics.
Best for
- People with dry, sensitive, or eczema-prone skin
- Anyone looking for a sulfate-free, gentle cleanser
Use caution if
- Individuals with a confirmed soy allergy who prefer to avoid any soy-derived ingredients
Usage tips
Safety summary
Potassium Lauroyl Hydrolyzed Soy Protein is considered safe for use in cosmetics. It has a low irritation and comedogenic risk, making it suitable for sensitive skin. The Cosmetic Ingredient Review (CIR) panel has evaluated similar amino-acid surfactants and found them safe at typical use concentrations.
Research notes
Research on amino-acid-based surfactants, including this ingredient, shows they have excellent skin compatibility and low irritation potential compared to traditional sulfates. Studies indicate they maintain skin barrier integrity while effectively removing dirt and oil.
Common label clues
- Typical concentration
- 1% to 10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics globally, including by the FDA (US) and EU CosIng database, with no known restrictions.
- Common uses
- Facial cleansers, Body washes, Shampoos, Conditioners, Makeup removers
- Environmental note
- Derived from renewable plant sources (soy and coconut/palm oil). It is biodegradable, but sourcing of palm oil should be checked for sustainability certifications.
Good to know
- This ingredient is often listed near the top of ingredient lists in sulfate-free cleansers.
- It is biodegradable and considered more environmentally friendly than many traditional surfactants.
Common questions
What is Potassium Lauroyl Hydrolyzed Soy Protein in beauty products?
This ingredient is a gentle cleanser made by combining lauric acid (from coconut or palm oil) with hydrolyzed soy protein. It works like a mild soap that removes dirt and oil without leaving your skin feeling tight or dry. Because it's derived from natural sources and is very gentle, it's often used in products for sensitive skin.
What does Potassium Lauroyl Hydrolyzed Soy Protein do in a beauty product?
It lowers the surface tension between water and oil, allowing dirt and sebum to be rinsed away. Unlike harsher sulfates, it has a larger molecular structure that doesn't penetrate the skin barrier, so it cleanses without causing irritation or excessive dryness.
Is Potassium Lauroyl Hydrolyzed Soy Protein safe for most people?
Potassium Lauroyl Hydrolyzed Soy Protein is considered safe for use in cosmetics. It has a low irritation and comedogenic risk, making it suitable for sensitive skin. The Cosmetic Ingredient Review (CIR) panel has evaluated similar amino-acid surfactants and found them safe at typical use concentrations.
Who should be careful with Potassium Lauroyl Hydrolyzed Soy Protein?
Individuals with a confirmed soy allergy who prefer to avoid any soy-derived ingredients
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.