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 20,769
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

Fragrance Ingredient

Cyclamen Aldehyde Acetal

CYCLAMEN ALDEHYDE ETHYLENEGLYCOL CYCLIC ACETAL

3.5

A synthetic floral scent ingredient that adds a pleasant cyclamen fragrance but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclamen Aldehyde Diethyl Acetal

CYCLAMEN ALDEHYDE DIETHYL ACETAL

3.5

A synthetic floral scent ingredient that adds a pleasant fragrance but may cause skin sensitivity in some people.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Antioxidant

Cyclanthera Pedata Fruit Extract

CYCLANTHERA PEDATA FRUIT EXTRACT

3.8

A gentle, antioxidant-rich fruit extract that may help calm skin and fight environmental stress, though research is still limited.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Cell-communicating agent

Cyclic GMP

Sodium Guanine Cyclic Monophosphate

3.8

A cell-signaling molecule that may help strengthen the skin barrier and improve hydration, but research is still early.

Irritation

low

Source

synthetic

beautyskincarecell-communicating ingredient
Read ingredient review

Fragrance

Cyclized Lemon Eucalyptus Oil

CYCLIZED EUCALYPTUS CITRIODORA LEAF/TWIG OIL

3.8

A processed lemon eucalyptus oil used mainly for scent; may offer mild skin conditioning but poses a moderate risk of irritation for sensitive skin.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Humectant

Cyclo PEG-6

CYCLO PEG-6

3.5

A gentle synthetic humectant that helps hydrate skin and improve product texture, but offers no unique benefits over more common alternatives.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Skin conditioning agent

Cyclocarboxypropyloleic Acid

CYCLOCARBOXYPROPYLOLEIC ACID

4.0

A synthetic lipid that mimics natural skin fats to support the moisture barrier, with early research suggesting it may help reduce water loss and improve skin comfort.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Antioxidant

Cyclocarya Paliurus Leaf Extract

CYCLOCARYA PALIURUS LEAF EXTRACT

3.8

A gentle, plant-derived antioxidant that may help protect skin from environmental stress, though research is still early and mostly lab-based.

Irritation

low

Source

natural

beautyskincareantioxidant
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Stabilizer

Cyclodextrin

Cyclodextrin

4.0

Cyclodextrin is a gentle, sugar-based molecule that helps stabilize and deliver active ingredients deeper into the skin without irritation.

Irritation

low

Source

natural

beautyskincarestabilizer
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Stabilizer

Cyclodextrin Crosspolymer

Cyclodextrin Crosspolymer

4.0

A gentle, starch-derived powder that helps stabilize and slowly release active ingredients, making formulas more effective and less irritating.

Irritation

low

Source

semi-synthetic

beautyskincarestabilizer
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Emulsifier

Cyclodextrin Laurate

Cyclodextrin Laurate

4.0

A gentle, starch-based ingredient that helps stabilize and deliver active ingredients without irritation.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Fragrance Ingredient

Cyclododecanal Dimethyl Acetal

CYCLODODECANAL DIMETHYL ACETAL

3.5

A synthetic scent ingredient that adds a pleasant note to products but offers no skincare benefit and may be unnecessary for sensitive skin.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclododecyl Acetate

CYCLODODECYL ACETATE

3.5

A synthetic scent ingredient that provides a fresh, woody aroma but may cause irritation for sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclododecyl Formate

CYCLODODECYL FORMATE

3.5

Cyclododecyl Formate is a synthetic fragrance ingredient that adds a pleasant scent but may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Emollient

Cycloethoxymethicone

Cycloethoxymethicone

3.8

A gentle silicone that improves product feel and spreadability with a low risk of irritation or clogged pores.

Irritation

low

Source

synthetic

beautyskincaresilicone
Read ingredient review

Emollient

Cyclohexadecanol

CYCLOHEXADECANOL

3.8

A gentle synthetic emollient that improves product feel and spreadability without common irritation.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Fragrance

Cyclohexadecenone

8-CYCLOHEXADECENONE

3.5

A synthetic musk-like fragrance that adds a pleasant scent but offers no skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Solvent

Cyclohexane

CYCLOHEXANE

3.5

Cyclohexane is a fast-evaporating solvent that helps dissolve oils and makeup, but it can be drying and potentially irritating for sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincaresolvent
Read ingredient review

Solvent

Cyclohexane Dimethanol

CYCLOHEXANE DIMETHANOL

3.5

A synthetic solvent that helps products spread and dry evenly, but offers no direct skin benefit.

Irritation

low

Source

synthetic

beautyskincaresolvent
Read ingredient review

pH Adjuster

Cyclohexanecarboxylic Acid

Cyclohexanecarboxylic Acid

3.5

A mild synthetic acid that helps balance product pH and gently exfoliates, but research on its long-term skin benefits is limited.

Irritation

moderate

Source

synthetic

beautyskincarepH adjuster
Read ingredient review

Soothing agent

Cyclohexanediol Bis-Methylcrotonate

CYCLOHEXANEDIOL BIS-METHYLCROTONATE

4.0

A synthetic soothing ingredient that helps reduce visible redness and stinging, making it a good option for sensitive skin.

Irritation

low

Source

synthetic

beautyskincaresoothing agent
Read ingredient review

Emollient

Cyclohexanediol Dicaprylate

Cyclohexanediol Dicaprylate

4.0

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

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Solvent

Cyclohexanol

CYCLOHEXANOL

2.5

Cyclohexanol is a synthetic solvent used in small amounts; it has moderate irritation potential and is not a beneficial skincare ingredient.

Irritation

moderate

Source

synthetic

beautyskincaresolvent
Read ingredient review

Solvent

Cyclohexanone

CYCLOHEXANONE

1.5

Cyclohexanone is a strong solvent with significant irritation and safety concerns; it is rarely used in leave-on skincare and is best avoided in daily products.

Irritation

high

Source

synthetic

beautyskincaresolvent
Read ingredient review

Fragrance Ingredient

Cyclohexanone Diethyl Acetal

Cyclohexanone Diethyl Acetal

3.5

A synthetic fragrance ingredient that adds a fresh scent but offers no skincare benefits and may trigger sensitivity in some people.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Emollient

Cyclohexasiloxane

Cyclohexasiloxane

4.0

A lightweight silicone that creates a smooth, silky feel on skin and hair without clogging pores.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Fragrance Ingredient

Cyclohexene Acetate

3,5-DIMETHYL-3-CYCLOHEXENE-1-METHYL ACETATE

3.5

A synthetic scent ingredient that adds a pleasant aroma but offers no skincare benefits and may cause sensitivity in some people.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Component

Cyclohexene Carbaldehyde

3,6-DIMETHYL-3-CYCLOHEXENE-1-CARBALDEHYDE

3.5

A synthetic scent ingredient that adds a fresh note but may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexene Methanol

2,4-DIMETHYL-3-CYCLOHEXENE-1-METHANOL

3.5

A synthetic scent ingredient that adds a pleasant aroma but offers no skincare benefits; safe at low levels but may cause sensitivity in some.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexenyl Cyclohexanone

2-CYCLOHEXENYL CYCLOHEXANONE

3.5

A synthetic fragrance compound that adds scent but offers no skincare benefits; may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexenylmethyl Butanol

CYCLOHEXENYLMETHYL BUTANOL

3.5

A synthetic scent ingredient that adds a fresh, green note but may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexyl Acetate

Cyclohexyl Acetate

3.5

A synthetic fragrance ingredient that adds a fruity, floral scent but offers no skincare benefit and may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexyl Butyrate

Cyclohexyl Butyrate

3.5

Cyclohexyl Butyrate is a synthetic fragrance ingredient that adds a fruity, sweet scent to products, but it offers no skincare benefits and may be a concern for those with fragrance sensitivities.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexyl Crotonate

Cyclohexyl Crotonate

3.5

Cyclohexyl Crotonate is a synthetic fragrance ingredient that adds a pleasant scent to products but may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexyl Cyclopenteneacetate

CYCLOHEXYL CYCLOPENTENEACETATE

3.8

A synthetic fragrance compound that adds a pleasant floral note, but offers no skincare benefit and may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Soothing Agent

Cyclohexyl Hydroxybutyramide

Cyclohexyl Hydroxybutyramide

3.8

A synthetic soothing ingredient that helps calm redness and irritation without being greasy or heavy.

Irritation

low

Source

synthetic

beautyskincaresoothing agent
Read ingredient review

Fragrance Ingredient

Cyclohexyl Isovalerate

Cyclohexyl Isovalerate

3.8

A synthetic fragrance ingredient that adds a pleasant scent but offers no skincare benefits; generally safe at low concentrations.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Film Former

Cyclohexyl Methacrylate

Cyclohexyl Methacrylate

3.0

Cyclohexyl Methacrylate is a synthetic film-forming ingredient used mainly in nail products to create a hard, glossy finish, but it can be a skin sensitizer for some people.

Irritation

moderate

Source

synthetic

beautynail carefilm former
Read ingredient review

Fragrance Ingredient

Cyclohexyl Phenethyl Ether

CYCLOHEXYL PHENETHYL ETHER

3.5

A synthetic fragrance ingredient that adds a pleasant floral scent but offers no skincare benefits and may cause sensitivity in some people.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Film Former

Cyclohexyl Phenylcarbamate

CYCLOHEXYL PHENYLCARBAMATE

3.5

A synthetic film-former that helps products feel smooth and last longer, but with limited published safety data.

Irritation

low

Source

synthetic

beautyskincarefilm-former
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Solvent

Cyclohexyl Toluate

Cyclohexyl Toluate

3.5

Cyclohexyl Toluate is a synthetic ester that helps dissolve other ingredients and leaves a light, non-greasy feel on skin.

Irritation

low

Source

synthetic

beautyskincaresolvent
Read ingredient review

Fragrance Ingredient

Cyclohexyl-4-Methylpentan-2-One

CYCLOHEXYL-4-METHYLPENTAN-2-ONE

3.5

A synthetic fragrance compound that adds scent but offers no skincare benefit; generally safe at low levels but may cause irritation in sensitive individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance ingredient

Cyclohexylcyclohexanone

CYCLOHEXYLCYCLOHEXANONE

3.5

A synthetic fragrance ingredient that adds a floral, woody scent; generally considered safe at low concentrations but may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexylethanol

Cyclohexylethanol

3.5

A synthetic fragrance ingredient that adds a floral note to products; generally safe at low levels but may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexylethyl Acetate

CYCLOHEXYLETHYL ACETATE

3.5

A synthetic scent ingredient that adds a pleasant aroma but offers no skincare benefit; safe for most but may cause sensitivity in those with fragrance allergies.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance ingredient

Cyclohexylethyl Butyrate

CYCLOHEXYLETHYL BUTYRATE

3.8

A synthetic fragrance ingredient that adds a fruity, floral scent to products; generally considered safe at low levels but may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexylethyl Crotonate

Cyclohexylethyl Crotonate

3.5

A synthetic fragrance ingredient that adds a pleasant scent but offers no skincare benefits; safe at low levels but may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Humectant

Cyclohexylglycerin

Cyclohexylglycerin

4.0

A gentle, synthetic humectant that hydrates skin and helps preserve formulas, making it a popular alternative to parabens.

Irritation

low

Source

synthetic

beautyskincarehumectant
Read ingredient review

Fragrance Ingredient

Cyclohexylidenecyclohexanone

CYCLOHEXYLIDENECYCLOHEXANONE

3.5

A synthetic scent ingredient that adds a warm, woody note but offers no skincare benefit and may be unnecessary for sensitive noses.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

UV Filter

Cyclohexylidenediphenylmethane

CYCLOHEXYLIDENEDIPHENYLMETHANE

4.0

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

Irritation

low

Source

synthetic

beautyskincaresunscreen
Read ingredient review

Fragrance

Cyclohexylpentanol Derivative

2-METHYL 5-CYCLOHEXYLPENTANOL

3.5

A synthetic fragrance ingredient that adds a fresh floral scent but offers no skincare benefits; safe at low levels but may cause sensitivity in some.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Cyclohexylpropanol

CYCLOHEXYLPROPANOL

3.5

A synthetic scent ingredient that adds a pleasant floral note but offers no skincare benefit and may cause sensitivity in some people.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Anti-aging

Cyclohydroxyprolyl Serine

Cyclohydroxyprolyl Serine

4.0

A synthetic peptide that signals skin to produce more collagen, helping reduce fine lines and improve firmness with low irritation risk.

Irritation

low

Source

synthetic

beautyskincarepeptide
Read ingredient review

Emollient

Cyclomethicone

Cyclomethicone

4.0

A lightweight, volatile silicone that provides a silky feel and helps other ingredients spread evenly, but its environmental persistence raises concerns.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Fragrance Ingredient

Cyclooctenyl Methyl Carbonate

CYCLOOCTENYL METHYL CARBONATE

3.5

A synthetic fragrance ingredient that adds a fresh scent but offers no skincare benefits and may be a concern for those sensitive to fragrance.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review