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 20,303
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

Film Former

Polyamide-1

POLYAMIDE-1

3.8

Polyamide-1 is a synthetic film-former that helps makeup and hair products resist water and last longer, with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincarehaircarefilm-former
Read ingredient review

Texture Enhancer

Polyamide-12

Polyamide-12

4.0

Polyamide-12 is a safe, non-irritating synthetic powder that improves product feel and controls shine without clogging pores.

Irritation

low

Source

synthetic

beautyskincaretexturizer
Read ingredient review

Film Former

Polyamide-14 Copolymer

LAUROLACTAM/POLY(1,4-BUTANEDIOL)-14/DODECANEDIOIC ACID COPOLYMER

3.8

A synthetic film-former that helps makeup and skincare stay put without feeling heavy or sticky.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyamide-6

Polyamide-6

3.8

Polyamide-6 is a safe, synthetic film-former that helps cosmetics stay put without clogging pores.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyaminoethyl Methacrylate

POLYDIMETHYLAMINOETHYL METHACRYLATE

3.5

A synthetic film-former that helps products stay put, but may feel stiff or heavy on some skin and hair types.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Preservative

Polyaminopropyl Biguanide

POLYAMINOPROPYL BIGUANIDE

4.0

An effective, low-irritation preservative that helps keep your products safe from germs, but has faced some regulatory scrutiny in Europe.

Irritation

low

Source

synthetic

beautyskincarepreservative
Read ingredient review

Film Former

Polyanthranilic Acid Sulfate

Polyanthranilic Acid Sulfate

3.0

A synthetic film-former that helps products last longer, but with very limited published research on its safety or efficacy.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Humectant

Polybeta-Alanine

POLYBETA-ALANINE

4.0

A gentle, water-loving polymer that plumps skin and reduces fine lines without irritation.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Film Former

Polybutanediol PEG Ether

POLY(1,2-BUTANEDIOL)-55/PEG-90 PENTAERYTHRITYL ETHER

3.5

A synthetic polymer that helps products spread smoothly and resist water, generally considered safe for most skin types.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Humectant

Polybutanediol Xylitol Ether

POLY(1,2-BUTANEDIOL)-40 XYLITOL ETHER

4.0

A gentle, sugar-derived humectant that helps hydrate skin without stickiness, though research on its long-term benefits is still limited.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Binder

Polybutene

Polybutene

3.8

Polybutene is a safe synthetic ingredient that helps products spread smoothly and stay put, but it offers no active skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Humectant

Polybutylene Glycol-10

POLYBUTYLENE GLYCOL-10

4.0

A gentle, synthetic humectant that helps hydrate skin and improve product feel without common irritation.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Film Former

Polybutylene Glycol/MDI Copolymer

POLYBUTYLENE GLYCOL/MDI COPOLYMER

3.5

A synthetic polymer that helps makeup and sunscreen stay put longer, but it's not a skincare active and may feel heavy on some skin types.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polybutylene Succinate

POLYBUTYLENE SUCCINATE

3.8

A biodegradable synthetic polymer that helps create a flexible, peelable film in masks and improves product texture.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polybutylene Terephthalate

POLYBUTYLENE TEREPHTHALATE

3.5

A synthetic plastic-like polymer that helps makeup last longer and resist smudging, but offers no skincare benefit.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polycaprolactone

POLYCAPROLACTONE

3.8

Polycaprolactone is a gentle synthetic polymer that helps products spread smoothly and leaves a light, non-greasy film on skin.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polycaprolactone Film Former

BIS-METHACRYLOYLOXYETHYLCARBAMOYL POLYCAPROLACTONE

3.8

A synthetic film former that helps products stay put without feeling heavy or sticky.

Irritation

low

Source

synthetic

beautyskincarefilm former
Read ingredient review

Texture enhancer

Polycaprylylsilsesquioxane

Polycaprylylsilsesquioxane

4.0

A gentle silicone powder that gives a silky, matte finish and helps products glide on smoothly.

Irritation

low

Source

synthetic

beautyskincaretexturizer
Read ingredient review

Film Former

Polychlorotrifluoroethylene

POLYCHLOROTRIFLUOROETHYLENE

3.5

A synthetic film-forming polymer that creates a breathable, water-resistant barrier on the skin, often used to enhance product longevity and protect against environmental stressors.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polycyclopentadiene

Polycyclopentadiene

3.0

A synthetic polymer that helps create smooth, water-resistant films in color cosmetics, but offers no active skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Antioxidant

Polydatin

POLYDATIN

4.0

Polydatin is a gentle antioxidant that helps protect skin from environmental stress and may support a more even tone, but it's less studied than its close relative resveratrol.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Emollient

Polydecene

Polydecene

4.0

A silky, lightweight synthetic oil that hydrates without greasiness, ideal for oily or sensitive skin.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Humectant

Polydextrose

POLYDEXTROSE

3.8

Polydextrose is a gentle, water-soluble humectant that helps attract moisture to the skin and leaves a light, non-sticky feel.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Film Former

Polydiallyl Phthalate

POLYDIALLYL PHTHALATE

3.5

Polydiallyl phthalate is a synthetic film-former that helps products stay put, but its use is limited due to concerns about phthalate-related safety and environmental persistence.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polydiethylsiloxane

POLYDIETHYLSILOXANE

4.0

A gentle silicone that helps products glide on smoothly and leaves skin feeling soft without clogging pores.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Antioxidant

Polydihydroxyindole

Polydihydroxyindole

3.8

A synthetic melanin-inspired ingredient that may help protect skin from oxidative stress, but research is still early.

Irritation

low

Source

synthetic

beautyskincareantioxidant
Read ingredient review

Film Former

Polydipentene

POLYDIPENTENE

3.5

Polydipentene is a synthetic polymer that helps create a flexible, water-resistant film on skin or lashes, but it offers no active skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Emollient

Polyester Emollient Blend

POLYPENTAERYTHRITYL C5-10 ACID ESTERS

4.0

A lightweight synthetic emollient that spreads easily and leaves a silky finish without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Film Former

Polyester Film Former

POLYPENTAERYTHRITYL TEREPHTHALATE

3.8

A synthetic film former that helps products stay put and resist water, but offers no active skincare benefit.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyester-32

Polyester-32

3.5

A synthetic film former that helps makeup and sunscreen stay put longer, especially in water or sweat.

Irritation

low

Source

synthetic

beautyskincarecosmetic
Read ingredient review

Film Former

Polyester-5 Polymer

ISOPHTHALIC ACID/PENTAERYTHRITOL CROSSPOLYMER BENZOATE/ISOSTEARATE

4.0

A synthetic polymer that helps makeup and skincare stay put without feeling heavy or sticky.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyethylacrylate

Polyethylacrylate

3.8

Polyethylacrylate is a safe, synthetic film-former that helps products stay put and resist water, but it may feel slightly tight or heavy on very dry or sensitive skin.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Thickener

Polyethylene

POLYETHYLENE

3.5

Polyethylene is a versatile synthetic polymer that helps products feel smooth and spread easily, but its use as microbeads has raised environmental concerns.

Irritation

low

Source

synthetic

beautyskincarecosmetic
Read ingredient review

Film Former

Polyethylene Isoterphthalate

POLYETHYLENE ISOTEREPHTHALATE

3.0

A synthetic polymer that helps products form a flexible film on skin or lashes, but offers no active skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyethylene Naphthalate

POLYETHYLENE NAPHTHALATE

2.0

Polyethylene Naphthalate is a synthetic polymer used mainly in packaging and as a film former in cosmetics, but it offers no direct skin benefit and raises environmental concerns.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyethylene Terephthalate

POLYETHYLENE TEREPHTHALATE

3.5

A common plastic polymer that helps products form a durable, glossy film, but raises environmental concerns due to its non-biodegradable nature.

Irritation

low

Source

synthetic

beautyskincarefilm former
Read ingredient review

Film Former

Polyethylene/IPDI Copolymer

POLYETHYLENE/ISOPROPYL MALEATE/MA COPOLYOL

3.5

A synthetic film-former that helps products resist water and last longer, but offers no active skincare benefit.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Humectant

Polyethylglutamate

Polyethylglutamate

4.0

Polyethylglutamate is a gentle, amino-acid-based humectant that helps skin hold onto moisture without feeling sticky or heavy.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
Read ingredient review

Film Former

Polyethylhexyl Acrylate

Polyethylhexyl Acrylate

3.8

A synthetic film-former that helps makeup and sunscreen stay put longer without feeling heavy or sticky.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Film Former

Polyethylhexyl Methacrylate

Polyethylhexyl Methacrylate

3.8

A synthetic film-former that helps makeup last longer and resist water, but may feel heavy on very sensitive skin.

Irritation

low

Source

synthetic

beautyskincarefilm-former
Read ingredient review

Humectant

Polygamma-Glutamic Acid

POLYGAMMA-GLUTAMIC ACID

4.4

A standout hydrator that can hold thousands of times its weight in water, often outperforming hyaluronic acid in moisture retention.

Irritation

low

Source

natural

beautyskincarehumectant
Read ingredient review

Humectant

Polyglutamic Acid

Polyglutamic Acid

4.5

Polyglutamic acid is a standout hydrator that can hold up to four times more water than hyaluronic acid, making it a great choice for dry or dehydrated skin.

Irritation

low

Source

biotech

beautyskincarehumectant
Read ingredient review

Emulsifier

Polyglyceride Ester Blend

Hydroxystearic/Linolenic/Oleic Polyglycerides

4.0

A gentle, plant-derived emulsifier that helps create stable, creamy textures while also softening the skin.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
Read ingredient review

Emulsifier

Polyglyceride Fatty Acid Blend

OLEIC/LINOLEIC/LINOLENIC POLYGLYCERIDES

4.0

A gentle, plant-derived emulsifier that helps blend oil and water in skincare, with mild skin-conditioning benefits.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
Read ingredient review

Humectant

Polyglycerin-10

Polyglycerin-10

4.5

Polyglycerin-10 is a gentle, non-sticky humectant that hydrates skin without the tackiness of glycerin.

Irritation

low

Source

natural

beautyskincarehumectant
Read ingredient review

Humectant

Polyglycerin-20

Polyglycerin-20

4.3

A gentle, effective humectant that hydrates without stickiness, making it a great alternative to glycerin for sensitive or acne-prone skin.

Irritation

low

Source

natural

beautyskincarehumectant
Read ingredient review

Humectant

Polyglycerin-3

Polyglycerin-3

4.3

A lightweight, non-sticky humectant that hydrates without clogging pores, making it a great choice for oily and sensitive skin types.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Humectant

Polyglycerin-4

Polyglycerin-4

4.3

Polyglycerin-4 is a lightweight humectant that hydrates without stickiness, making it a great option for oily or combination skin.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Humectant

Polyglycerin-40

Polyglycerin-40

4.2

A gentle, non-sticky humectant that hydrates the skin without the tackiness of glycerin, making it a great choice for lightweight formulas.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Humectant

Polyglycerin-6

Polyglycerin-6

4.3

A lightweight, non-sticky humectant that hydrates without clogging pores, ideal for oily and sensitive skin types.

Irritation

low

Source

natural

beautyskincarehumectant
Read ingredient review

Emulsifier

Polyglyceryl Dimer Soyate

Polyglyceryl Dimer Soyate

4.0

A gentle, plant-derived emulsifier that helps create stable, creamy formulas without harsh detergents.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
Read ingredient review