Beauty ingredient research

Beauty ingredients explained in plain English

Browse the review database to understand what an ingredient is, what it does in a beauty formula, when it is useful, and when it deserves caution across skincare, haircare, bodycare, makeup, and more.

20769

Reviewed ingredients

524

Low-concern standouts

2884

Need usage caution

Showing 60 of 1,342
AllUV absorberUV filterabrasiveabsorbentacne treatmentactiveactive ingredientadhesivealkalizing agentamino acidanti-aginganti-androgenanti-cavityanti-cavity agentanti-inflammatoryanti-irritantanticariesanticavity agentantidandruffantifungalantimicrobialantioxidantantiperspirantantiplaqueastringentbarrier repairbarrier supportbarrier-repairbarrier-supportbinderbinding agentbiotechbiotechnologybond-builderbotanicalbotanical extractbotanical oilbotanical waterbrighteningbrightening agentbufferbuffering agentcell-communicating ingredientceramidechelating agentchemicalchemical intermediateclaycleansercleansingcleansing agentcolorantconditionerconditioningconditioning agentcooling agentcosmeticcosmetic additivecosmetic colorantcosmetic ingredientcosmetic pigmentcosmetic powdercosmetic-texturizercosmetic-waxcosmeticscrosslinking agentdelivery agentdelivery systemdenaturantdeodorantdeodorant agentdepigmenting agentdepilatorydepilatory agentdesensitizing agentdyedye intermediatedye precursordye-intermediateemollientemulsifierenzymeessential oilexfoliantexperimentaleyelashfermentfilm formerfilm-formerfilm-formingfilm-forming agentfirming agentfixativeflavoring agentformulationfragrancefragrance ingredientfunctional ingredientgashair carehair colorhair coloranthair conditionerhair dyehair removalhair-carehair-colorhaircarehumectantindustrialinsecticideintermediatelashlash carelash enhancerlash-and-browlip carelipidmakeupmarine extractmasking agentmicrobiomemicrobiome modulatormineralmoisturizernail carenail-careocclusiveoilopacifieropacifying agentoptical agentoral careotheroxidative dyeoxidative dye precursoroxidizing agentpH adjusterpain reliefpenetration enhancerpeptidepersonal careph adjusterpharmaceuticalpheromonepigmentplant oilplasticizerpolymerpolymer precursorprebioticprescription-drugpreservativepreservative boosterprobioticprocessing agentprocessing aidpropellantproteinpurifyingreducing agentretinoidscalp caresebum regulatorsebum-regulatorself-tannerself-tanningsensory additivesensory agentsensory modifiersiliconeskin barrierskin barrier supportskin conditionerskin conditioningskin conditioning agentskin lighteningskin protectantskin-conditioningskin-conditioning agentskin-identicalskin-identical ingredientskin-lighteningskin-lightening agentskincaresolventsoothingsoothing agentstabilizerstimulantsunscreensurfactantsyntheticsynthetic colorantsynthetic dyesynthetic resinsynthetic-coloranttexture enhancertexturizerthickenertoneruv-absorberuv-filtervasoactivevasodilatorviscosity controlviscosity controllingviscosity controlling agentvitaminwax

Emulsifier

PEG-33 Castor Oil

PEG-33 Castor Oil

4.0

A gentle, water-soluble emulsifier that helps mix oils into water-based formulas without clogging pores.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-35 Almond Glycerides

PEG-35 ALMOND GLYCERIDES

4.0

A mild, almond-derived emulsifier that helps blend water and oil in creams and lotions without heavy irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-35 Castor Oil

PEG-35 Castor Oil

4.0

PEG-35 Castor Oil is a reliable emulsifier that helps mix oil and water, making it a staple in many cleansers and creams without causing irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-35 Hydrogenated Castor Oil

PEG-35 HYDROGENATED CASTOR OIL

4.0

A well-tolerated emulsifier that helps mix oil and water in your products, but may feel heavy on very oily skin.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emollient

PEG-35 Lanolin

PEG-35 Lanolin

3.8

A gentle, water-friendly lanolin derivative that moisturizes and helps blend oil and water in formulas, but may not suit those with wool allergies.

Irritation

low

Source

semi-synthetic

beautyskincareemollientemulsifier
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Emulsifier

PEG-35 Soy Glycerides

PEG-35 SOY GLYCERIDES

4.0

A reliable, low-irritation emulsifier that helps create smooth, stable creams and lotions without clogging pores.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-36 Oleate

PEG-36 Oleate

3.5

PEG-36 Oleate is a safe and effective emulsifier that helps mix oil and water, but it may be a concern for those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-36 Stearate

PEG-36 Stearate

3.8

A reliable emulsifier that keeps creams and lotions stable, but may not be ideal for very sensitive or compromised skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Castor Oil

PEG-4 Castor Oil

4.0

A safe, effective emulsifier that helps mix oil and water in your products, with a low risk of irritation or clogged pores.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Diisostearate

PEG-4 Diisostearate

3.5

A reliable synthetic emulsifier that helps mix oil and water, but may be slightly pore-clogging for acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Dilaurate

PEG-4 Dilaurate

3.5

PEG-4 Dilaurate is a workhorse emulsifier that helps mix water and oil, but it may be slightly pore-clogging for acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Distearate

PEG-4 Distearate

3.8

A safe, widely used synthetic emulsifier that helps blend oil and water in creams and lotions, but may not suit those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Distearyl Ether

PEG-4 Distearyl Ether

4.0

A gentle synthetic emulsifier that helps create stable, creamy formulas without common irritation concerns.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Glyceryl Distearate

PEG-4 Glyceryl Distearate

4.0

A gentle, semi-synthetic emulsifier that helps create stable, creamy textures with low irritation potential.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Glyceryl Tristearate

PEG-4 Glyceryl Tristearate

4.0

A gentle synthetic emulsifier that helps create stable, creamy textures in skincare without significant irritation or clogging concerns.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Isostearate

PEG-4 Isostearate

3.8

A reliable synthetic emulsifier that helps oil and water mix in your skincare, but it's not a star active ingredient.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Laurate

PEG-4 Laurate

3.5

PEG-4 Laurate is a workhorse emulsifier that helps mix oil and water, but it may be mildly irritating or pore-clogging for sensitive or acne-prone skin.

Irritation

moderate

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Montanate

PEG-4 Montanate

3.5

A gentle synthetic emulsifier that helps mix water and oil in creams and lotions, with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Oleamide

PEG-4 OLEAMIDE

3.5

PEG-4 Oleamide helps mix oil and water in cleansers and creams, but its synthetic nature and potential for irritation make it a cautious choice for sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Oleate

PEG-4 Oleate

3.8

PEG-4 Oleate helps mix oil and water in products, but may be slightly irritating or pore-clogging for sensitive or acne-prone skin.

Irritation

moderate

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Olivate

PEG-4 Olivate

4.0

A gentle, olive-derived emulsifier that helps blend water and oil in cleansers and creams, with low irritation potential.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 PEG-12 Dimethicone

PEG-4 PEG-12 Dimethicone

4.0

A gentle silicone emulsifier that improves product texture and stability, generally safe for most skin types.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Sorbitan Stearate

PEG-4 SORBITAN STEARATE

4.0

A gentle emulsifier that helps create stable, creamy formulas without common irritation concerns.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-4 Sorbitan Triisostearate

PEG-4 SORBITAN TRIISOSTEARATE

4.0

A reliable synthetic emulsifier that keeps water and oil mixed in creams and lotions, generally well-tolerated by most skin types.

Irritation

low

Source

synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

PEG-4 Stearate

PEG-4 Stearate

3.8

PEG-4 Stearate is a safe, widely used emulsifier that helps products feel smooth, but it may be slightly pore-clogging for acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Distearate

PEG-40 Distearate

3.8

A reliable synthetic emulsifier that stabilizes formulas but may not suit those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Glyceryl Cocoate

PEG-40 Glyceryl Cocoate

3.8

A gentle, coconut-derived emulsifier that helps cleansers foam and rinse cleanly without stripping the skin.

Irritation

low

Source

semi-synthetic

beautyskincarecleansingemulsifier
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Emulsifier

PEG-40 Glyceryl Isostearate

PEG-40 Glyceryl Isostearate

4.0

A reliable emulsifier that keeps oil and water mixed in your products, but may not suit those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

PEG-40 Glyceryl Stearate

PEG-40 Glyceryl Stearate

4.0

A gentle emulsifier that keeps oil and water mixed in creams and lotions, generally well-tolerated by most skin types.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

PEG-40 Glyceryl Trioleate

PEG-40 Glyceryl Trioleate

3.8

A reliable emulsifier that helps mix oil and water, but may be too heavy for very oily or acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Isostearate

PEG-40 Isostearate

4.0

A reliable emulsifier that helps create stable, creamy formulas without common irritation.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Jojoba Acid

PEG-40 Jojoba Acid

4.0

A gentle, plant-derived emulsifier that helps blend oil and water in cleansers and creams, with a low risk of irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Jojoba Alcohol

PEG-40 Jojoba Alcohol

4.2

A gentle, jojoba-derived emulsifier that helps mix oil and water without stripping the skin.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Lanolin

PEG-40 Lanolin

3.8

A gentle, water-friendly emulsifier that helps blend oil and water in creams and cleansers, but may not suit those with wool allergies.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Olive Glycerides

PEG-40 Olive Glycerides

4.0

A mild, olive-derived emulsifier that helps mix oil and water in cleansers and creams, with a low risk of irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Sorbitan Lanolate

PEG-40 SORBITAN LANOLATE

4.0

A reliable, low-irritation emulsifier that helps blend oils and water, but may not suit those with lanolin sensitivity.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Sorbitan Laurate

PEG-40 Sorbitan Laurate

3.8

A reliable emulsifier that keeps formulas stable, but may be too heavy for very oily or acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Sorbitan Oleate

PEG-40 Sorbitan Oleate

3.8

A widely used synthetic emulsifier that is generally safe and non-irritating for most skin types.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Sorbitan Perisostearate

PEG-40 SORBITAN PERISOSTEARATE

3.8

A reliable synthetic emulsifier that helps blend oil and water, generally well-tolerated but may not suit those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

PEG-40 Sorbitan Peroleate

PEG-40 SORBITAN PEROLEATE

3.8

A reliable emulsifier that helps oil and water mix, but may not suit those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

PEG-40 Sorbitan Stearate

PEG-40 Sorbitan Stearate

4.0

A gentle, widely used emulsifier that helps create stable, creamy formulas without common irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-40 Sorbitan Tetraoleate

PEG-40 Sorbitan Tetraoleate

3.5

A reliable synthetic emulsifier that keeps oil and water mixed in your products, but it may not suit those avoiding ethoxylated ingredients.

Irritation

low

Source

synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

PEG-40 Soy Sterol

PEG-40 Soy Sterol

4.0

A well-tolerated emulsifier that helps create stable, creamy textures while offering mild skin conditioning.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-41 Polybutylene Glycol Ether

HYDROGENATED DIMER DILINOLEYL PEG-41/POLY(1,2-BUTANEDIOL)-18 DIMETHYL ETHER

4.0

A gentle synthetic polymer that helps stabilize formulas and gives a smooth, non-greasy feel.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-42 Babassu Glycerides

PEG-42 Babassu Glycerides

4.0

A mild, semi-synthetic emulsifier derived from babassu oil that helps blend water and oil in cleansers and creams without stripping the skin.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-44 Castor Oil

PEG-44 Castor Oil

4.0

A gentle emulsifier that helps mix oil and water in cleansers and shampoos, with a low risk of irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-45 Hydrogenated Castor Oil

PEG-45 Hydrogenated Castor Oil

3.8

A gentle, oil-based emulsifier that helps mix water and oil in formulas, but may feel heavy on very oily skin.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-45 Palm Kernel Glycerides

PEG-45 PALM KERNEL GLYCERIDES

3.8

A gentle emulsifier that helps blend oil and water in skincare products, generally well-tolerated but derived from palm kernel oil, which raises sustainability concerns.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-45 Safflower Glycerides

PEG-45 SAFFLOWER GLYCERIDES

4.0

A mild, plant-derived emulsifier that helps water and oil mix in your skincare, with a low risk of irritation or clogged pores.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emulsifier

PEG-45 Stearate

PEG-45 Stearate

4.0

PEG-45 Stearate is a widely used emulsifier that helps create stable, creamy textures, but it may contain trace impurities from its manufacturing process.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Emulsifier

PEG-5 Glyceryl Isostearate

PEG-5 Glyceryl Isostearate

3.8

A reliable synthetic emulsifier that helps create stable, creamy textures, but may be too heavy for very oily or acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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