Ingredient review
Dihydrocholeth-15
INCI: Dihydrocholeth-15
A gentle emulsifier that helps blend oil and water in formulas, with mild skin-conditioning benefits.
In plain English
Dihydrocholeth-15 is a semi-synthetic ingredient made by attaching a chain of ethylene glycol (PEG) to a cholesterol-like molecule. In skincare, it acts as an emulsifier, meaning it helps mix water and oil so the product stays smooth and doesn't separate. It also has a mild skin-conditioning effect, leaving skin feeling slightly softer. Because it's derived from a cholesterol relative, it's considered very gentle and unlikely to clog pores or cause irritation.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
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
Useful, but context matters
Dihydrocholeth-15 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 Dihydrocholeth-15.
- 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 emulsifier created by reacting dihydrocholesterol (a hydrogenated form of cholesterol) with 15 units of ethylene oxide (PEG-15). It belongs to the PEG ether family and is used to stabilize oil-in-water emulsions.
How it works
Its molecule has a water-loving (hydrophilic) PEG chain and a fat-loving (lipophilic) cholesterol-like tail. When added to a formula, it positions itself at the interface of oil and water droplets, reducing surface tension and keeping the mixture stable. This prevents the product from separating into layers.
Pros
Gentle on skin
Derived from a cholesterol-like molecule, it is very mild and unlikely to cause stinging, redness, or irritation, even for sensitive skin types.
Effective stabilizer
It reliably prevents oil and water from separating, giving lotions and creams a smooth, consistent texture that lasts.
Cons and cautions
Synthetic processing concerns
As a PEG derivative, it may carry trace impurities like 1,4-dioxane if not properly purified. Reputable brands use high-quality, purified grades to minimize this risk.
Not eco-friendly
PEG compounds are not readily biodegradable and are derived from petroleum, which may be a concern for environmentally conscious consumers.
Best for
- People with sensitive or reactive skin
- Anyone using oil-and-water blend products like lotions or creams
Use caution if
- Those who prefer completely natural or plant-based ingredients
- Individuals with known sensitivity to PEG compounds (rare)
Usage tips
Safety summary
Dihydrocholeth-15 is considered safe for use in cosmetics at typical concentrations. The main safety concern is potential contamination with 1,4-dioxane during manufacturing, but reputable suppliers use purification steps to keep levels well below safety limits. Skin irritation and allergy are very rare.
Research notes
Safety assessments by the Cosmetic Ingredient Review (CIR) panel have concluded that PEG derivatives like dihydrocholeth-15 are safe for use in cosmetics when formulated to be non-irritating. There is limited specific research on this exact compound, but its chemical class is well-studied and widely used.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US (FDA), EU (CosIng), and many other regions. Manufacturers must ensure PEG compounds are purified to limit impurities like 1,4-dioxane.
- Common uses
- Moisturizers, Cleansers, Serums, Lotions
- Environmental note
- PEG derivatives are not readily biodegradable and may persist in aquatic environments. However, they are used in low concentrations and are generally considered low-risk in rinse-off products.
Good to know
- Dihydrocholeth-15 is considered non-comedogenic and safe for acne-prone skin.
- It is often used in 'cholesterol-based' moisturizers that aim to mimic the skin's natural lipid barrier.
- The '15' in its name refers to the number of ethylene oxide units, which affects its water solubility.
Common questions
What is Dihydrocholeth-15 in beauty products?
Dihydrocholeth-15 is a semi-synthetic ingredient made by attaching a chain of ethylene glycol (PEG) to a cholesterol-like molecule. In skincare, it acts as an emulsifier, meaning it helps mix water and oil so the product stays smooth and doesn't separate. It also has a mild skin-conditioning effect, leaving skin feeling slightly softer. Because it's derived from a cholesterol relative, it's considered very gentle and unlikely to clog pores or cause irritation.
What does Dihydrocholeth-15 do in a beauty product?
Its molecule has a water-loving (hydrophilic) PEG chain and a fat-loving (lipophilic) cholesterol-like tail. When added to a formula, it positions itself at the interface of oil and water droplets, reducing surface tension and keeping the mixture stable. This prevents the product from separating into layers.
Is Dihydrocholeth-15 safe for most people?
Dihydrocholeth-15 is considered safe for use in cosmetics at typical concentrations. The main safety concern is potential contamination with 1,4-dioxane during manufacturing, but reputable suppliers use purification steps to keep levels well below safety limits. Skin irritation and allergy are very rare.
Who should be careful with Dihydrocholeth-15?
Those who prefer completely natural or plant-based ingredients Individuals with known sensitivity to PEG compounds (rare)
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.