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

Surfactant

Dihydroxyethyl Tallowamine Oxide

DIHYDROXYETHYL TALLOWAMINE OXIDE

3.5

An effective foam booster and surfactant, but may cause irritation for sensitive skin and raises ethical concerns due to its animal-derived origin.

Irritation

moderate

Source

semi-synthetic

beautyskincarecleansing
Read ingredient review

Pigment Modulator

Dihydroxyindole

DIHYDROXYINDOLE

3.5

Dihydroxyindole is a natural melanin precursor that may help enhance pigmentation and provide antioxidant benefits, but its cosmetic use is still emerging and not widely studied in humans.

Irritation

low

Source

natural

beautyskincarehair care
Read ingredient review

Surfactant

Dihydroxyisopropyl Palmoylpalmamide

DIHYDROXYISOPROPYL PALMOYLPALMAMIDE

3.5

A mild synthetic surfactant that helps create rich foam and improve cleansing texture, generally well-tolerated by most skin types.

Irritation

low

Source

synthetic

beautyskincaresurfactant
Read ingredient review

Antioxidant

Dihydroxymethoxy Dihydrochalcone

Dihydroxymethoxy Dihydrochalcone

4.0

A gentle synthetic antioxidant that helps brighten skin and fight signs of aging, with a good safety profile for most skin types.

Irritation

low

Source

synthetic

beautyskincareantioxidant
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Humectant

Dihydroxypropyl Arginine HCl

DIHYDROXYPROPYL ARGININE HCL

4.0

A gentle, water-loving amino acid derivative that helps attract moisture to the skin and may support a healthier barrier.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
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Hair conditioning agent

Dihydroxypropyl Cystine

DIHYDROXYPROPYL CYSTINE

4.0

A gentle amino acid derivative that helps reinforce hair structure, making strands feel stronger and less prone to breakage.

Irritation

low

Source

semi-synthetic

beautyskincarehair care
Read ingredient review

Eyelash growth stimulant

Dihydroxypropyl Didehydrolatanoprostamide

DIHYDROXYPROPYL DIDEHYDROLATANOPROSTAMIDE

3.5

A synthetic prostaglandin analog that can enhance eyelash and brow growth but carries risks of irritation and potential eye-area side effects.

Irritation

moderate

Source

synthetic

beautyskincarelash-and-brow
Read ingredient review

Film Former

Dihydroxypropyl Hydrolyzed Casein

DIHYDROXYPROPYL HYDROLYZED CASEIN

3.8

A gentle, modified milk protein that forms a protective film on hair and skin to lock in moisture and smooth texture.

Irritation

low

Source

semi-synthetic

beautyskincarefilm-former
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Surfactant

Dihydroxypropyl N-Methyllauramide

DIHYDROXYPROPYL N-METHYLLAURAMIDE

4.0

A gentle, low-irritation surfactant that helps create a rich lather and improve cleansing without stripping the skin.

Irritation

low

Source

semi-synthetic

beautyskincaresurfactant
Read ingredient review

Antistatic Agent

Dihydroxypropyltrimonium Chloride

DIHYDROXYPROPYLTRIMONIUM CHLORIDE

4.0

A gentle antistatic and conditioning ingredient that helps reduce flyaways and improve hair feel without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Preservative

Diiodomethyltolylsulfone

DIIODOMETHYLTOLYLSULFONE

3.5

An effective preservative but can be a skin sensitizer, so it's best suited for rinse-off products or low concentrations.

Irritation

moderate

Source

synthetic

beautyskincarepreservative
Read ingredient review

Emollient

Diisoamyl Malate

Diisoamyl Malate

4.0

A silky, non-greasy emollient that feels lightweight on skin and helps other ingredients spread evenly.

Irritation

low

Source

semi-synthetic

beautyskincareemollient
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Emollient

Diisoamyl Sebacate

Diisoamyl Sebacate

4.0

A silky, non-greasy emollient that softens skin without clogging pores, ideal for lightweight formulas.

Irritation

low

Source

natural

beautyskincareemollient
Read ingredient review

Emollient

Diisobutyl Adipate

DIISOBUTYL ADIPATE

3.8

A lightweight synthetic emollient that helps products spread smoothly without a greasy feel, generally considered safe for most skin types.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisobutyl Glutarate

DIISOBUTYL GLUTARATE

4.0

A lightweight, non-greasy emollient that helps products spread smoothly and leaves skin feeling soft without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Solvent

Diisobutyl Ketone

2,6-DIMETHYL-4-HEPTANONE

2.5

A synthetic solvent used mainly in fragrances; not a primary skincare active and may cause irritation at higher levels.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Emollient

Diisobutyl Maleate

Diisobutyl Maleate

3.8

A lightweight synthetic emollient that helps products spread smoothly and leaves skin feeling soft without greasiness.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Solvent

Diisobutyl Oxalate

DIISOBUTYL OXALATE

3.5

Diisobutyl Oxalate is a synthetic solvent that helps dissolve other ingredients and creates a silky feel, but it has limited research on long-term skin effects.

Irritation

low

Source

synthetic

beautyskincaresolvent
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Surfactant

Diisobutyl Sodium Sulfosuccinate

DIISOBUTYL SODIUM SULFOSUCCINATE

3.8

A strong synthetic cleanser that effectively removes oil and dirt but may be drying or irritating for sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincarecleanser
Read ingredient review

Emollient

Diisobutyl Succinate

Diisobutyl Succinate

4.0

A lightweight, non-greasy emollient that helps products glide on smoothly without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisocetyl Adipate

Diisocetyl Adipate

4.0

A lightweight synthetic oil that softens skin without clogging pores, commonly used to improve product texture.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisodecyl Adipate

DIISODECYL ADIPATE

4.3

A lightweight synthetic emollient that softens skin without clogging pores, commonly used to improve product texture and spreadability.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Plasticizer

Diisodecyl Phthalate

Diisodecyl Phthalate

1.0

Diisodecyl phthalate is a plasticizer with limited cosmetic use; it is not a typical skincare ingredient and is best avoided due to potential health concerns.

Irritation

low

Source

synthetic

beautyskincareplasticizer
Read ingredient review

Plasticizer

Diisoheptyl Phthalate

Diisoheptyl Phthalate

1.0

Diisoheptyl Phthalate is a synthetic plasticizer with no proven skincare benefit and potential health concerns; it is best avoided in leave-on products.

Irritation

moderate

Source

synthetic

beautyskincareplasticizer
Read ingredient review

Emollient

Diisononyl Adipate

Diisononyl Adipate

4.0

A silky, lightweight emollient that hydrates without clogging pores, making it a great choice for oily or acne-prone skin.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisononyl Ether

Diisononyl Ether

4.0

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

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisononyl Isoeicosanedioate

Diisononyl Isoeicosanedioate

4.0

A lightweight synthetic ester that softens skin without clogging pores, commonly used to improve product texture.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisooctyl Adipate

Diisooctyl Adipate

3.8

A lightweight synthetic emollient that helps products spread easily and leaves skin feeling soft, but may clog pores for some people.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisooctyl Sebacate

Diisooctyl Sebacate

4.0

A lightweight, non-greasy emollient that helps skincare products spread easily and leaves skin feeling soft without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisooctyl Succinate

Diisooctyl Succinate

4.0

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

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisopropyl Adipate

DIISOPROPYL ADIPATE

4.0

A silky, non-greasy emollient that helps products spread easily and leaves skin feeling soft without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Fragrance Ingredient

Diisopropyl Benzaldehyde

DIISOPROPYL BENZALDEHYDE

3.5

Diisopropyl Benzaldehyde 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

Emollient

Diisopropyl Ethyl Cinnamate

DIISOPROPYL ETHYL CINNAMATE

3.5

A lightweight synthetic emollient that helps soften skin and improve product texture, but it's not a star ingredient with proven long-term benefits.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

UV Absorber

Diisopropyl Methyl Cinnamate

DIISOPROPYL METHYL CINNAMATE

3.5

Diisopropyl Methyl Cinnamate is a synthetic UV filter that helps protect skin from sun damage, but its use is limited compared to more common sunscreen ingredients.

Irritation

low

Source

synthetic

beautyskincaresunscreen
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Solvent

Diisopropyl Oxalate

Diisopropyl Oxalate

3.8

Diisopropyl Oxalate is a synthetic ingredient that helps other ingredients dissolve and spread smoothly, with a low risk of irritation or clogged pores.

Irritation

low

Source

synthetic

beautyskincaresolvent
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Emollient

Diisopropyl Sebacate

DIISOPROPYL SEBACATE

4.3

A lightweight, non-greasy emollient that softens skin and improves product feel, with a low risk of irritation or clogged pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisostearyl Adipate

Diisostearyl Adipate

4.0

A lightweight, silky emollient that hydrates without clogging pores, ideal for oily and combination skin types.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisostearyl Fumarate

DIISOSTEARYL FUMARATE

4.0

A gentle, non-greasy emollient that helps soften and smooth the skin without clogging pores.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emulsifier

Diisostearyl Lauroyl Glutamate

DIISOSTEARYL LAUROYL GLUTAMATE

4.3

A mild, amino-acid-based emulsifier that helps blend oil and water in creams and lotions while leaving skin feeling soft and smooth.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
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Emollient

Diisostearyl Malate

Diisostearyl Malate

4.2

A reliable, silky emollient that improves texture and pigment spread without clogging pores or irritating skin.

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emollient

Diisostearyl Sebacate

Diisostearyl Sebacate

4.0

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

Irritation

low

Source

synthetic

beautyskincareemollient
Read ingredient review

Emulsifier

Diisotridecyl Lauroyl Glutamate

DIISOTRIDECYL LAUROYL GLUTAMATE

4.3

A mild, amino-acid-derived emulsifier that helps create stable, creamy textures with very low irritation potential.

Irritation

low

Source

semi-synthetic

beautyskincareemulsifier
Read ingredient review

Surfactant

Dilaureth-10 Phosphate

DILAURETH-10 PHOSPHATE

4.0

A gentle synthetic surfactant that effectively cleanses without stripping the skin's natural moisture barrier.

Irritation

low

Source

synthetic

beautyskincaresurfactant
Read ingredient review