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

Emollient

Phenyl Propyl Trimethicone

PHENYL PROPYL TRIMETHICONE

4.3

A gentle silicone that makes skin feel silky and smooth without clogging pores, ideal for improving product texture and wear.

Irritation

low

Source

synthetic

beautyskincaresilicone
Read ingredient review

UV Absorber

Phenyl Salicylate

PHENYL SALICYLATE

3.5

Phenyl salicylate offers mild UV protection but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincaresunscreen
Read ingredient review

Film Former

Phenyl Silicone Crosspolymer

Diphenylmethylsiloxy Phenyl Methicone/Phenyl Silsesquioxane Crosspolymer

4.0

A gentle silicone that gives a silky, non-greasy finish and helps other ingredients spread evenly.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antioxidant

Phenyl Timonacic

PHENYL TIMONACIC

3.5

Phenyl Timonacic is a synthetic antioxidant that may help protect skin from environmental stress, but research is still emerging.

Irritation

low

Source

synthetic

beautyskincareantioxidant
Read ingredient review

Emollient

Phenyl Trimethicone

Phenyl Trimethicone

4.0

A lightweight silicone that gives skin and hair a silky feel without clogging pores, but may not suit everyone who avoids silicones.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde

PHENYLACETALDEHYDE

3.5

Phenylacetaldehyde adds a floral, hyacinth-like scent to products but can be a skin sensitizer for some individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Diethyl Acetal

PHENYLACETALDEHYDE DIETHYL ACETAL

3.8

A synthetic floral scent ingredient that can be a skin sensitizer for some people, especially at higher concentrations.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Digeranyl Acetal

PHENYLACETALDEHYDE DIGERANYL ACETAL

3.5

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

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Diisoamyl Acetal

PHENYLACETALDEHYDE DIISOAMYL ACETAL

3.5

A synthetic fragrance ingredient that adds pleasant floral notes but may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Dimethyl Acetal

PHENYLACETALDEHYDE DIMETHYL ACETAL

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Ethylene Glycol Acetal

PHENYLACETALDEHYDE ETHYLENEGLYCOL CYCLIC ACETAL

3.5

A synthetic floral scent ingredient that can cause skin irritation in sensitive individuals, but is generally safe at low concentrations.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Glyceryl Acetal

PHENYLACETALDEHYDE GLYCERYL 1,3-CYCLIC ACETAL

3.8

A synthetic floral scent ingredient that is generally safe at low levels but offers no skincare benefit beyond fragrance.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylacetaldehyde Glyceryl Cyclic Acetals

PHENYLACETALDEHYDE GLYCERYL CYCLIC ACETALS

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Exfoliant

Phenylacetic Acid

Phenylacetic Acid

3.8

Phenylacetic acid is a gentle exfoliant that may help brighten skin and improve texture, but research is still emerging compared to more established AHAs.

Irritation

low

Source

synthetic

beautyskincareexfoliant
Read ingredient review

Humectant

Phenylalanine

PHENYLALANINE

4.0

A gentle amino acid that helps skin hold onto moisture and supports a healthy barrier, but it's not a standout active on its own.

Irritation

low

Source

natural

beautyskincarehumectantamino acid
Read ingredient review

Skin conditioning agent

Phenylalanine Peptide Complex

TRIS(PEG-2 PHENYLALANYLCARBOXAMIDO) CYCLOHEXANE

4.0

A synthetic peptide that may help improve skin firmness and reduce fine lines, with a good safety profile for most skin types.

Irritation

low

Source

synthetic

beautyskincarepeptide
Read ingredient review

UV Filter

Phenylbenzimidazole Sulfonate

POTASSIUM PHENYLBENZIMIDAZOLE SULFONATE

4.0

A widely used, water-soluble UVB filter that offers effective sunburn protection without a heavy feel.

Irritation

low

Source

synthetic

beautyskincaresunscreen
Read ingredient review

UV Absorber

Phenyldimethoxyacetophenone

Phenyldimethoxyacetophenone

3.8

A synthetic stabilizer that protects your skincare products from breaking down in light, but it's not a primary sunscreen agent.

Irritation

low

Source

synthetic

beautyskincarestabilizer
Read ingredient review

Fragrance Ingredient

Phenylethoxyacetaldehyde

Phenylethoxyacetaldehyde

3.5

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

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Tyrosinase Inhibitor

Phenylethyl Resorcinol

PHENYLETHYL RESORCINOL

4.3

A well-researched brightening ingredient that can be effective but may cause irritation for sensitive skin.

Irritation

moderate

Source

synthetic

beautyskincarebrightening agent
Read ingredient review

Antioxidant

Phenylethylidene-bis-indole

PHENYLETHYLIDENE-BIS-INDOLE

3.5

A synthetic antioxidant that may help protect skin from environmental stress, but research is still early.

Irritation

low

Source

synthetic

beautyskincareantioxidant
Read ingredient review

Fragrance

Phenylethylpyridine

Phenylethylpyridine

3.5

Phenylethylpyridine is a synthetic fragrance ingredient with limited safety data; it may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

Phenylhexenone

5-PHENYLHEX-4-EN-2-ONE

3.5

A synthetic fragrance compound that adds a pleasant scent but may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylisohexanol

Phenylisohexanol

4.0

A synthetic floral scent ingredient that is generally well-tolerated but offers no skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

Phenylmethylpentanal

PHENYLMETHYLPENTANAL

3.5

Phenylmethylpentanal is a synthetic fragrance ingredient that adds a floral scent but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Enzyme Inhibitor

Phenylmethylsulfonyl Fluoride

PHENYLMETHYLSULFONYL FLUORIDE

3.5

A synthetic enzyme blocker that helps preserve active ingredients but may cause irritation at higher concentrations.

Irritation

moderate

Source

synthetic

beautyskincarepreservative
Read ingredient review

Preservative

Phenylparaben

PHENYLPARABEN

2.5

Phenylparaben is a synthetic preservative that is effective but controversial due to potential endocrine-disrupting concerns; it is now rarely used in modern skincare.

Irritation

moderate

Source

synthetic

beautyskincarepreservative
Read ingredient review

Preservative booster

Phenylpentanol

PHENYLPENTANOL

4.0

Phenylpentanol is a gentle synthetic ingredient that helps preserve products and lightly conditions skin, making it a safer alternative to harsher preservatives.

Irritation

low

Source

synthetic

beautyskincarepreservative
Read ingredient review

Fragrance

Phenylpropane

PHENYLPROPANE

3.5

Phenylpropane is a synthetic fragrance ingredient that adds scent but offers no skincare benefits; it may cause irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

Phenylpropanol

PHENYLPROPANOL

3.8

Phenylpropanol is a mild fragrance ingredient that also helps preserve formulas, but it offers no direct skin benefit.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

Phenylpropionaldehyde

PHENYLPROPIONALDEHYDE

3.5

Phenylpropionaldehyde is a synthetic fragrance compound that adds a floral scent but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Phenylpropyl Acetate

1-PHENYLPROPYL ACETATE

3.5

A synthetic fragrance ester that adds a sweet, floral scent to products but offers no skincare benefits.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Fragrance

Phenylpropyl Tetrahydrofuran

2-PHENYLPROPYLTETRAHYDROFURAN

3.5

A synthetic scent ingredient that adds a pleasant floral note but offers no skincare benefit and may be a concern for those sensitive to fragrance.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Depilatory agent

Phenylthioglycolic Acid

Phenylthioglycolic Acid

3.5

Phenylthioglycolic acid is a synthetic depilatory ingredient that breaks down hair keratin, but it can be irritating and is not intended for leave-on skincare.

Irritation

moderate

Source

synthetic

beautyskincaredepilatory
Read ingredient review

Photosensitizer

Pheophorbide A PEG Complex

PHEOPHORBIDE A AMIDO PEG-45 AMIDO DISTEAROYL GLYCEROPHOSPHOETHANE

3.5

A light-activated chlorophyll derivative that may boost collagen and reduce pigmentation, but requires professional handling due to potential irritation.

Irritation

moderate

Source

semi-synthetic

beautyskincareactive
Read ingredient review

Soothing Agent

Phlomis Root Extract

Phlomis Koraiensis Root Extract

3.8

A gentle plant-root extract with early research suggesting antioxidant and soothing benefits, but human studies are limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Antioxidant

Phloretin

Phloretin

4.3

A gentle apple-derived antioxidant that helps even skin tone and defends against pollution and UV stress.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Antioxidant

Phloridzin

Phloridzin

4.0

A gentle apple-derived antioxidant that helps even skin tone and fights early signs of aging without irritation.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Antioxidant

Phloridzinyl Glucoside

Phloridzinyl Glucoside

4.0

A gentle, plant-derived antioxidant that may help brighten skin and reduce the look of dark spots without irritation.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Antioxidant

Phloroglucinol Trimethyl Ether

PHLOROGLUCINOL TRIMETHYL ETHER

3.5

Phloroglucinol Trimethyl Ether is a synthetic antioxidant that may help protect skin from environmental stress, but research on its specific benefits in cosmetics is still limited.

Irritation

low

Source

synthetic

beautyskincareantioxidant
Read ingredient review

Antioxidant

Phlox Seed Extract

Phlox Drummondii Seed Extract

3.5

A gentle, plant-derived antioxidant extract that may help protect skin from environmental stress, though research is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Soothing Agent

Phoenician Juniper Gum Extract

Juniperus Phoenicea Gum Extract

3.8

A gentle, plant-based extract that may help calm skin and fight environmental stress, though research is still early.

Irritation

low

Source

natural

beautyskincaresoothing agent
Read ingredient review

Antioxidant

Phoenician Juniper Wood Extract

Juniperus Phoenicea Wood Extract

3.8

A gentle botanical extract with antioxidant potential, but research is still early and benefits are not yet proven in human skin.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Fragrance

Phoenician Juniper Wood Oil

JUNIPERUS PHOENICEA WOOD OIL RECTIFIED

3.8

A fragrant wood oil with mild antimicrobial potential, best suited for those who enjoy botanical scents and have resilient skin.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Exfoliant

Phonolite

Phonolite

3.5

Phonolite is a natural volcanic mineral powder that gently exfoliates and absorbs excess oil without harsh chemicals.

Irritation

low

Source

natural

beautyskincareexfoliant
Read ingredient review

Antioxidant

Phormidium Ferment

Phormidium Ferment

4.0

A gentle, antioxidant-rich ferment from blue-green algae that may help calm skin and defend against environmental stress.

Irritation

low

Source

biotech

beautyskincareantioxidant
Read ingredient review

Soothing Agent

Phormidium Ferment Filtrate

Phormidium Elemis Lysate Filtrate

4.0

A gentle, biotech-derived microalgae ferment that may help calm skin and fight oxidative stress, though research is still emerging.

Irritation

low

Source

biotech

beautyskincaresoothing agent
Read ingredient review

Antioxidant

Phormidium Persicinum Extract

Phormidium Persicinum Extract

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review

Antioxidant

Phormidium Uncinatum Extract

Phormidium Uncinatum Extract

3.8

A gentle, antioxidant-rich algae extract that may help calm skin and fight environmental stress, but research is still early.

Irritation

low

Source

natural

beautyskincareantioxidant
Read ingredient review