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

Solvent

Triethyl Citrate

Triethyl Citrate

4.0

Triethyl citrate is a gentle, plant-derived solvent and plasticizer that helps products spread evenly and keeps formulas stable, with a low risk of irritation.

Irritation

low

Source

semi-synthetic

beautyskincaresolvent
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Solvent

Triethyl Phosphate

Triethyl Phosphate

3.5

A synthetic solvent that helps thin out thick formulas and dissolve other ingredients, generally considered safe at cosmetic levels.

Irritation

low

Source

synthetic

beautyskincaresolvent
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pH Adjuster

Triethylamine

TRIETHYLAMINE

2.5

Triethylamine is an effective pH adjuster but can be irritating at higher concentrations; it's rarely used in leave-on products.

Irritation

moderate

Source

synthetic

beautyskincarepH adjuster
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pH Adjuster

Triethylamine Hexylsalicylate

Triethylamine Hexylsalicylate

3.0

A synthetic pH adjuster that helps stabilize salicylate ingredients, but may cause irritation in sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincarepH adjuster
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Humectant

Triethylene Glycol

TRIETHYLENE GLYCOL

3.5

Triethylene glycol is a safe, effective humectant that helps keep skin hydrated and improves product feel, but it's less common than glycerin or propylene glycol.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Film Former

Triethylene Glycol Rosinate

Triethylene Glycol Rosinate

3.5

A pine-derived film former that helps makeup and sunscreen stay put, but may feel stiff or tacky on skin.

Irritation

low

Source

semi-synthetic

beautyskincarefilm-former
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Chelating Agent

Triethylenetetramine HCl

TRIETHYLENETETRAMINE HCL

3.5

A synthetic chelator that helps preserve formula integrity by neutralizing trace metals, but it is rarely highlighted as a standalone active.

Irritation

low

Source

synthetic

beautyskincarestabilizer
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Emollient

Triethylhexanoin

TRIETHYLHEXANOIN

4.2

A lightweight, non-greasy emollient that improves product texture and skin feel without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
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Emollient

Triethylhexyl Citrate

Triethylhexyl Citrate

4.0

A lightweight, non-greasy emollient derived from citric acid that improves product texture and skin feel.

Irritation

low

Source

semi-synthetic

beautyskincareemollient
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Emollient

Triethylhexyl Trimellitate

Triethylhexyl Trimellitate

4.0

A lightweight, non-greasy emollient that helps products glide on smoothly and resist water, with a low risk of irritation or clogged pores.

Irritation

low

Source

synthetic

beautyskincareemollient
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Anti-wrinkle agent

Trifluoroacetyl Tripeptide-2

TRIFLUOROACETYL TRIPEPTIDE-2

4.0

A synthetic peptide that may help soften expression lines and improve skin firmness, but human data is limited.

Irritation

low

Source

synthetic

beautyskincarepeptide
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Film Former

Trifluoromethyl C1-4 Alkyl Dimethicone

TRIFLUOROMETHYL C1-4 ALKYL DIMETHICONE

3.8

A high-performance fluorinated silicone that creates a durable, water-resistant barrier on skin and hair, but its environmental persistence raises sustainability concerns.

Irritation

low

Source

synthetic

beautyskincarehaircarefilm former
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Eyelash Conditioner

Trifluoromethyl Dechloro Ethylcloprostenolamide

TRIFLUOROMETHYL DECHLORO ETHYLCLOPROSTENOLAMIDE

3.0

A synthetic ingredient that may help eyelashes appear longer and fuller, but it comes with potential side effects and limited long-term safety data.

Irritation

moderate

Source

synthetic

beautyskincareconditioning agent
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Eyelash growth stimulant

Trifluoromethyl Dehydrolatanoprost

Trifluoromethyl Dehydrolatanoprost

3.5

A synthetic prostaglandin analog that may promote eyelash growth but carries risks of irritation and potential side effects.

Irritation

moderate

Source

synthetic

beautyskincarelash enhancer
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UV Filter

Trifluoromethylbipyridyl Bromobenzimidazole

TRIFLUOROMETHYLBIPYRIDYL BROMOBENZIMIDAZOLE

3.8

A synthetic UV filter that helps protect skin from sun damage, but its use is limited to certain regions and formulations due to regulatory and stability considerations.

Irritation

low

Source

synthetic

beautyskincaresunscreen
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Skin conditioning

Trifluoropropyl Cyclopentasiloxane

TRIFLUOROPROPYL CYCLOPENTASILOXANE

3.8

A lightweight fluorinated silicone that enhances product feel and spreadability, but its environmental persistence raises concerns.

Irritation

low

Source

synthetic

beautyskincaresilicone
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Solvent

Trifluoropropyl Cyclotrisiloxane

TRIFLUOROPROPYL CYCLOTRISILOXANE

3.5

A lightweight silicone that helps products glide on smoothly and dry quickly, but its environmental persistence raises concerns.

Irritation

low

Source

synthetic

beautyskincaresilicone
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Film Former

Trifluoropropyl Dimethicone

TRIFLUOROPROPYL DIMETHICONE

3.8

A fluorinated silicone that creates a breathable, water-resistant barrier on skin, offering a silky feel without heavy greasiness.

Irritation

low

Source

synthetic

beautyskincaresilicone
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Film Former

Trifluoropropyl Dimethicone Crosspolymer

TRIFLUOROPROPYL DIMETHICONE/TRIFLUOROPROPYL DIVINYLDIMETHICONE CROSSPOLYMER

4.0

A high-performance silicone that helps products stay put and resist water without feeling heavy or greasy.

Irritation

low

Source

synthetic

beautyskincarehaircarefilm-former
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Film Former

Trifluoropropyl Dimethiconol

TRIFLUOROPROPYL DIMETHICONOL

4.0

A high-performance silicone that creates a smooth, water-resistant film on skin and hair without feeling heavy.

Irritation

low

Source

synthetic

beautyskincarehaircare
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Film Former

Trifluoropropyl Methicone

TRIFLUOROPROPYL METHICONE

4.0

A lightweight, water-resistant silicone that gives a smooth, non-greasy feel but may not suit those avoiding silicones entirely.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Emulsifier

Triglycereth-7 Citrate

TRIGLYCERETH-7 CITRATE

4.0

A gentle, citrate-modified emulsifier that stabilizes formulas while offering mild skin conditioning, suitable for sensitive skin.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emollient

Triheptanoin

Triheptanoin

4.3

Triheptanoin is a silky, non-greasy emollient that hydrates and softens skin, making it a great choice for sensitive and oily skin types.

Irritation

low

Source

natural

beautyskincareemollient
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Emollient

Triheptylundecanoin

Triheptylundecanoin

4.0

A lightweight synthetic emollient that softens skin without a greasy feel, ideal for oilier or acne-prone skin types.

Irritation

low

Source

synthetic

beautyskincareemollient
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Emollient

Trihexyldecyl Citrate

Trihexyldecyl Citrate

4.0

A gentle, non-greasy emollient derived from citric acid and fatty alcohols that softens skin and improves product feel without clogging pores.

Irritation

low

Source

natural

beautyskincareemollient
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Antioxidant

Trihydroxyaurone

Trihydroxyaurone

3.8

A gentle antioxidant from the flavonoid family that may help calm skin and protect against environmental stress, though research is still early.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Trihydroxychalcone

TRIHYDROXYCHALCONE

4.0

Trihydroxychalcone is a gentle antioxidant that helps calm skin and defend against daily pollution and UV stress.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Trihydroxydihydrochalcone

Trihydroxydihydrochalcone

4.0

A gentle antioxidant that may help brighten skin and reduce signs of irritation, though research is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
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Emollient

Trihydroxymethoxystearin

Trihydroxymethoxystearin

4.0

A gentle synthetic emollient that makes products feel silky and spread easily without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
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Thickener

Trihydroxystearin

TRIHYDROXYSTEARIN

4.0

Trihydroxystearin is a reliable thickener and stabilizer that helps keep cosmetic products smooth and consistent without common irritation concerns.

Irritation

low

Source

semi-synthetic

beautyskincarethickener
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Emollient

Triisocetyl Citrate

Triisocetyl Citrate

4.3

A gentle, plant-derived emollient that hydrates and softens skin without clogging pores, ideal for sensitive and oily skin types.

Irritation

low

Source

natural

beautyskincareemollient
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Emollient

Triisodecyl Trimellitate

Triisodecyl Trimellitate

4.0

A lightweight synthetic emollient that gives a silky, non-greasy feel and is generally well-tolerated by most skin types.

Irritation

low

Source

synthetic

beautyskincareemollient
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Emollient

Triisononanoin

Triisononanoin

4.0

Triisononanoin is a lightweight, non-greasy emollient that softens skin and improves product feel without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
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pH Adjuster

Triisopropanolamine

Triisopropanolamine

3.5

Triisopropanolamine is a workhorse pH adjuster that helps keep your products stable and gentle, but it can be irritating in high concentrations or for sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincarepH adjuster
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Emollient

Triisopropyl Citrate

Triisopropyl Citrate

4.0

A lightweight, non-greasy emollient that helps skin feel soft and smooth without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
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Emollient

Triisopropyl Trilinoleate

Triisopropyl Trilinoleate

4.0

A lightweight synthetic ester that softens skin without clogging pores, ideal for oily or combination skin types.

Irritation

low

Source

synthetic

beautyskincareemollient
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Emollient

Triisostearin

Triisostearin

4.0

Triisostearin is a lightweight, non-greasy emollient that helps moisturize and improve product texture, with a low risk of irritation or clogged pores.

Irritation

low

Source

synthetic

beautyskincareemollient
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Emulsifier

Triisostearin PEG-6 Esters

Triisostearin PEG-6 Esters

3.8

A gentle synthetic emulsifier that helps create stable, creamy textures in skincare, but may not suit those avoiding PEG compounds.

Irritation

low

Source

synthetic

beautyskincareemulsifier
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Antioxidant

Triisostearoyl Ascorbate

TRIISOSTEAROYL 3-GLYCERYL ASCORBATE

4.3

A gentle, oil-soluble vitamin C that delivers brightening and antioxidant benefits with minimal irritation.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Emollient

Triisostearyl Citrate

Triisostearyl Citrate

4.0

A gentle, non-greasy emollient that helps soften skin and improve product texture, with a very low risk of irritation or clogged pores.

Irritation

low

Source

semi-synthetic

beautyskincareemollient
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Emollient

Triisostearyl Trilinoleate

Triisostearyl Trilinoleate

4.0

A gentle, plant-derived emollient that helps soften and smooth skin without clogging pores, commonly found in lip and makeup products.

Irritation

low

Source

natural

beautyskincareemollient
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Emollient

Triisotridecyl Trimellitate

Triisotridecyl Trimellitate

4.0

A lightweight, non-greasy emollient that helps soften skin and improve product texture without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Humectant

Trilactin

Trilactin

4.0

Trilactin is a gentle, hydrating exfoliant that helps smooth skin texture without the irritation often associated with stronger acids.

Irritation

low

Source

semi-synthetic

beautyskincarehumectantexfoliant
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Surfactant

Trilaneth-4 Phosphate

TRILANETH-4 PHOSPHATE

3.8

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

Irritation

low

Source

semi-synthetic

beautyskincaresurfactant
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Surfactant

Trilaureth-4 Phosphate

TRILAURETH-4 PHOSPHATE

3.8

A mild synthetic surfactant that helps cleansers foam and rinse cleanly, but may be slightly drying for very sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincaresurfactant
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Surfactant

Trilaureth-9 Citrate

TRILAURETH-9 CITRATE

4.0

A gentle, citrate-based surfactant that cleans without stripping the skin, making it a good choice for sensitive or dry skin types.

Irritation

low

Source

semi-synthetic

beautyskincaresurfactant
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Emollient

Trilaurin

Trilaurin

4.0

Trilaurin is a gentle, coconut-derived emollient that helps soften skin without clogging pores, making it a safe choice for most skin types.

Irritation

low

Source

natural

beautyskincareemollient
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Emollient

Trilauryl Citrate

Trilauryl Citrate

4.0

A gentle, non-greasy emollient that softens skin and improves the feel of creams and sunscreens without clogging pores.

Irritation

low

Source

semi-synthetic

beautyskincareemollient
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