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

Colorant

5-Amino-6-Chloro-o-Cresol

5-AMINO-6-CHLORO-O-CRESOL

3.0

A synthetic hair dye colorant that is generally safe when used as directed, but may cause irritation for sensitive individuals.

Irritation

moderate

Source

synthetic

beautyhair colorcolorant
Read ingredient review

Fragrance Ingredient

5-Hexen-2-One

5-HEXEN-2-ONE

3.0

5-Hexen-2-One is a synthetic fragrance ingredient with limited safety data; it may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Anti-aging agent

5-Melozol

5-Melozol

3.5

5-Melozol is a synthetic peptide that may help firm and smooth skin, but research is limited and it is not widely studied in peer-reviewed human trials.

Irritation

low

Source

synthetic

beautyskincarepeptide
Read ingredient review

Skin conditioning agent

5-Melozol Acetate

5-Melozol Acetate

3.5

5-Melozol Acetate is a synthetic compound that may help improve skin firmness and reduce fine lines, but research is still emerging and it is not as widely studied as more established anti-aging ingredients.

Irritation

low

Source

synthetic

beautyskincareanti-aging
Read ingredient review

Fragrance Ingredient

5-Methyl-2-Hepten-4-One

5-METHYL-2-HEPTEN-4-ONE

3.5

A synthetic scent ingredient that adds a fruity note but offers no skincare benefit and may be a concern for fragrance-sensitive individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

5-Methyl-Alpha-Ionone

5-METHYL-ALPHA-IONONE

3.5

A synthetic floral scent that can cause skin reactions in sensitive individuals, but is generally safe at low levels.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

5-Methyl-Beta-Ionone

5-METHYL-BETA-IONONE

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

5-Methylfuranone

5-METHYLFURANONE

3.5

A synthetic scent ingredient that adds a caramel-like aroma but offers no skincare benefits and may trigger sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

5-Nonen-2-One

5-NONEN-2-ONE

3.5

5-Nonen-2-One is a synthetic fragrance ingredient with limited safety data; it may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

5-Phenylhex-3-en-2-one

5-PHENYLHEX-3-EN-2-ONE

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Preservative Booster

5,5-Dimethylhydantoin

5,5-DIMETHYLHYDANTOIN

3.5

A synthetic preservative helper that boosts formula stability but offers no direct skin benefit.

Irritation

low

Source

synthetic

beautyskincarepreservative
Read ingredient review

Fragrance

5,9-Dimethyl-8-Decen-3-ol

5,9-DIMETHYL-8-DECEN-3-OL

3.5

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

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Preservative

6-Amino-2,4-Dichloro-m-Cresol HCl

6-AMINO-2,4-DICHLORO-M-CRESOL HCL

2.5

A strong synthetic preservative that effectively fights microbes but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarepreservative
Read ingredient review

Colorant Precursor

6-Amino-m-Cresol

6-AMINO-M-CRESOL

3.0

A synthetic dye intermediate used in permanent hair color; it can cause skin irritation in sensitive individuals and requires careful formulation to minimize risks.

Irritation

moderate

Source

synthetic

beautyhair-colordye-intermediate
Read ingredient review

Antioxidant

6-Hydroxyindole

6-HYDROXYINDOLE

3.5

A lab-made antioxidant with early promise for evening skin tone, but human studies are still scarce.

Irritation

low

Source

synthetic

beautyskincareantioxidant
Read ingredient review

Fragrance

6-Methyl Coumarin

6-METHYL COUMARIN

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

6-Methylquinoline

6-METHYLQUINOLINE

3.5

6-Methylquinoline is a synthetic fragrance ingredient that adds a warm, woody scent to products, but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance ingredient

6-Tert-Butylquinoline

6-TERT-BUTYLQUINOLINE

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

6,7-Dihydrolinalool

6,7-DIHYDROLINALOOL

3.5

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

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

6,8-Dimethyl-2-Nonanol

6,8-DIMETHYL-2-NONANOL

3.5

A synthetic scent ingredient that adds a pleasant floral note but offers no skincare benefit.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Skin conditioning agent

7-Dehydrocholesterol

7-DEHYDROCHOLESTEROL

4.0

A skin-friendly cholesterol derivative that helps reinforce the skin barrier and acts as a building block for vitamin D3 when exposed to UV light.

Irritation

low

Source

semi-synthetic

beautyskincareskin-identical ingredient
Read ingredient review

Skin conditioning agent

7-Dehydrocholesteryl Palmitate

7-DEHYDROCHOLESTERYL PALMITATE

3.8

A gentle, oil-soluble derivative of provitamin D3 that may help support skin barrier function, though human evidence is still limited.

Irritation

low

Source

semi-synthetic

beautyskincareskin conditioning
Read ingredient review

Fragrance Ingredient

8-Cedrene Epoxide

8-CEDRENE EPOXIDE

3.8

A woody fragrance ingredient that is generally safe at low concentrations but offers no skincare benefit beyond scent.

Irritation

low

Source

semi-synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

8-Methoxy-2,6-Dimethyloct-2-ene

8-METHOXY-2,6-DIMETHYLOCT-2-ENE

3.0

A synthetic fragrance ingredient that adds a fresh scent but offers no skincare benefits and may irritate sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

8-Tert-Butylquinoline

8-TERT-BUTYLQUINOLINE

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

9-Decenal

9-DECENAL

3.5

9-Decenal is a synthetic fragrance ingredient that adds a fresh, citrusy note to products but offers no direct skincare benefit.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

9-Decenyl Acetate

9-DECENYL ACETATE

3.5

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

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

9-Decenyl Propionate

9-DECENYL PROPIONATE

3.5

A synthetic fragrance ester that adds a pleasant scent to products; generally safe at low concentrations but may cause sensitivity in some individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Exfoliant

Abalone Shell Powder

ABALONE SHELL POWDER

3.5

A natural exfoliant from abalone shells that gently polishes skin but has limited research and may be too abrasive for sensitive skin.

Irritation

moderate

Source

natural

beautyskincareexfoliant
Read ingredient review

Soothing Agent

Abelmoschus Manihot Root Extract

Abelmoschus Manihot Root Extract

3.8

A gentle plant extract with antioxidant and soothing potential, but research is still early and benefits are not yet proven in large human studies.

Irritation

low

Source

natural

beautyskincaresoothing agent
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Antimicrobial

Abietic Acid

Abietic Acid

3.8

Abietic acid is a pine-derived compound with promising anti-acne and anti-inflammatory benefits, but it may cause irritation or clog pores in sensitive skin.

Irritation

moderate

Source

natural

beautyskincareantimicrobial
Read ingredient review

Emollient

Abietyl Alcohol

ABIETYL ALCOHOL

3.8

A gentle, plant-based fatty alcohol that softens skin and may help active ingredients absorb better, but it's less common and less studied than alternatives like cetyl alcohol.

Irritation

low

Source

natural

beautyskincareemollient
Read ingredient review

Soothing Agent

Abronia Villosa Leaf Extract

Abronia Villosa Leaf Extract

3.5

A gentle, plant-based extract with early evidence of soothing and antioxidant benefits, but more research is needed to confirm its effectiveness in skincare.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Antioxidant

Abrus Leaf Extract

Abrus Fruticulosus Leaf Extract

3.5

A gentle, antioxidant-rich plant extract that may help calm skin and fight free radicals, but research is still limited.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Antioxidant

Abrus Precatorius Meristem Cell Extract

Abrus Precatorius Meristem Cell Culture Extract

3.8

A plant stem cell extract that may help protect skin from environmental stress, but research is still emerging and it's not a proven anti-aging powerhouse.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Antioxidant

Abrus Precatorius Root Extract

Abrus Precatorius Root Extract

3.0

A traditional botanical extract with potential soothing and antioxidant benefits, but safety concerns around the plant's seeds limit its use in modern cosmetics.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
Read ingredient review

Antioxidant

Abrus Root Extract

Abrus Fruticulosus Root Extract

3.5

A gentle botanical extract with antioxidant potential, but research on its cosmetic benefits is still very limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Exfoliant

Acacia Arabica Bark Powder

Acacia Arabica Bark Powder

3.8

A gentle, natural exfoliating powder that helps remove dead skin cells and absorb excess oil, but research on its specific skincare benefits is limited.

Irritation

low

Source

natural

beautyskincareexfoliant
Read ingredient review

Astringent

Acacia Arabica Stem Bark Powder

Acacia Arabica Stem Bark Powder

3.8

A gentle botanical powder with traditional astringent benefits, but limited modern research to support strong skincare claims.

Irritation

low

Source

natural

beautyskincarebotanical
Read ingredient review

Astringent

Acacia Catechu Bark Powder

Acacia Catechu Bark Powder

3.8

A gentle, plant-based astringent that can help tighten pores and calm irritation, but may be drying for very sensitive skin.

Irritation

low

Source

natural

beautyskincareastringent
Read ingredient review

Film Former

Acacia Catechu Gum

Acacia Catechu Gum

3.5

A natural gum that helps create a light, temporary film on skin, often used to improve texture or hold ingredients together.

Irritation

low

Source

natural

beautyskincarefilm-former
Read ingredient review

Astringent

Acacia Catechu Leaf/Wood Powder

Acacia Catechu Leaf/Wood Powder

3.8

A gentle botanical powder that may help calm irritation and tighten pores, but research is limited and it can be drying for some skin types.

Irritation

low

Source

natural

beautyskincarebotanical
Read ingredient review

Absorbent

Acacia Catechu Seed Powder

Acacia Catechu Seed Powder

3.5

A gentle, natural absorbent powder from tree seeds that can help mattify skin and add texture to products, but research on its skincare benefits is limited.

Irritation

low

Source

natural

beautyskincareabsorbent
Read ingredient review

Antioxidant

Acacia Catechu Wood Extract

ACACIA CATECHU WOOD EXTRACT

3.8

A gentle botanical extract that helps tighten pores and fight free radicals, but research is mostly lab-based.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Cleansing Agent

Acacia Concinna Fruit Extract

Acacia Concinna Fruit Extract

4.0

A gentle, plant-derived cleanser and conditioner that can be a mild alternative to sulfates, especially for those with sensitive scalps or hair.

Irritation

low

Source

natural

beautyskincarehaircare
Read ingredient review

Cleansing Agent

Acacia Concinna Fruit Powder

Acacia Concinna Fruit Powder

4.0

A gentle, plant-based cleanser rich in saponins that can help clean hair and skin without stripping natural oils.

Irritation

low

Source

natural

beautyskincarehaircare
Read ingredient review

Emollient

Acacia Dealbata Flower Wax

ACACIA DEALBATA FLOWER WAX

4.0

A gentle, plant-based wax that adds richness and staying power to balms and creams without common irritation.

Irritation

low

Source

natural

beautyskincareemollient
Read ingredient review

Astringent

Acacia Decurrens Extract

Acacia Decurrens Extract

3.8

A gentle plant extract that may help tighten pores and fight free radicals, but research on its specific skin benefits is still limited.

Irritation

low

Source

natural

beautyskincareastringentantioxidant
Read ingredient review

Antioxidant

Acacia Decurrens Flower Extract

Acacia Decurrens Flower Extract

3.8

A gentle, antioxidant-rich flower extract that may help calm skin and fight free radical damage, though research is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Emollient

Acacia Decurrens Flower Wax

Acacia Decurrens Flower Wax

4.0

A gentle, plant-derived wax that helps lock in moisture and gives a smooth, velvety feel to skincare products.

Irritation

low

Source

natural

beautyskincareemollient
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Emollient

Acacia Decurrens Wax Ester

ACACIA DECURRENS/JOJOBA/SUNFLOWER SEED CERA/POLYGLYCERYL-3 ESTERS

4.0

A gentle, plant-based wax ester that helps soften skin and improve product texture without clogging pores.

Irritation

low

Source

natural

beautyskincareemollient
Read ingredient review

Emollient

Acacia Decurrens Wax Esters

Acacia Decurrens/Jojoba/Sunflower Seed Wax Polyglyceryl-3 Esters

4.3

A gentle, plant-based wax blend that helps create smooth, creamy textures while moisturizing the skin.

Irritation

low

Source

natural

beautyskincareemollient
Read ingredient review

Antioxidant

Acacia Farnesiana Extract

Acacia Farnesiana Flower/Stem Extract

3.8

A gentle botanical extract that may help calm skin and provide antioxidant support, though research on its cosmetic benefits is still emerging.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Soothing agent

Acacia Farnesiana Flower Extract

Acacia Farnesiana Flower Extract

3.8

A gentle, fragrant flower extract with antioxidant and soothing potential, but research on its cosmetic benefits is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Thickener

Acacia Farnesiana Gum

Acacia Farnesiana Gum

3.8

A gentle natural gum that helps thicken formulas and leaves a light, non-sticky film on skin.

Irritation

low

Source

natural

beautyskincarethickener
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Antioxidant

Acacia Farnesiana Stem Bark Extract

Acacia Farnesiana Stem Bark Extract

3.8

A gentle botanical extract with antioxidant potential, but research is limited and benefits are not yet well-established in human skin.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review