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 569
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

Film Former

Polyquaternium-109

Polyquaternium-109

4.0

A gentle, modern conditioning polymer that smooths hair and reduces static without the heavy feel of older polyquaterniums.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-112

Polyquaternium-112

4.0

Polyquaternium-112 is a gentle, synthetic polymer that smooths hair, reduces static, and improves texture without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-114

Polyquaternium-114

4.0

A gentle synthetic polymer that smooths hair and skin without heavy buildup, ideal for sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-18

Polyquaternium-18

4.0

A gentle synthetic polymer that smooths hair and skin by forming a thin, flexible film, but may cause buildup with frequent use.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic agent

Polyquaternium-20

POLYQUATERNIUM-20

4.0

A gentle synthetic polymer that smooths hair and reduces static without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-22

Polyquaternium-22

4.0

A synthetic conditioning polymer that smooths hair and skin without heavy buildup, but may not suit very fine or low-porosity hair types.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-27

Polyquaternium-27

4.0

A gentle synthetic polymer that smooths hair and reduces flyaways without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-33

Polyquaternium-33

4.0

Polyquaternium-33 is a gentle synthetic polymer that smooths hair and skin by forming a thin, flexible film, reducing static and improving texture without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-35

Polyquaternium-35

3.8

Polyquaternium-35 is a gentle, synthetic conditioning polymer that smooths hair and improves product feel without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Polyquaternium-38

Polyquaternium-38

3.8

A gentle conditioning polymer that smooths hair and adds slip without heavy buildup, but may not suit very fine or low-porosity hair if used in high amounts.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Polyquaternium-40

Polyquaternium-40

3.8

Polyquaternium-40 is a gentle conditioning polymer that helps reduce frizz and static while improving the feel of hair and skin, but it may cause buildup with frequent use.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-42

Polyquaternium-42

4.0

Polyquaternium-42 is a gentle synthetic polymer that smooths hair, reduces static, and improves manageability without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-44

Polyquaternium-44

4.0

A gentle, water-soluble conditioning polymer that smooths hair and fights frizz without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-47

POLYQUATERNIUM-47

4.0

A gentle conditioning polymer that smooths hair and skin without heavy buildup, ideal for sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-48

Polyquaternium-48

4.0

A gentle synthetic polymer that smooths hair and skin without heavy buildup, ideal for sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-49

Polyquaternium-49

4.0

A gentle synthetic polymer that smooths hair cuticles and reduces flyaways without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Antistatic Agent

Polyquaternium-5

Polyquaternium-5

4.0

A gentle synthetic polymer that smooths hair and reduces frizz without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-50

Polyquaternium-50

4.0

Polyquaternium-50 is a gentle conditioning polymer that helps hair feel soft and smooth without heavy buildup, and it's generally well-tolerated on skin.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-55

Polyquaternium-55

3.8

Polyquaternium-55 is a synthetic conditioning polymer that helps reduce static, smooth hair, and improve the feel of rinse-off products without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Polyquaternium-56

Polyquaternium-56

4.0

Polyquaternium-56 is a gentle synthetic polymer that helps hair feel smooth and reduces frizz without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-58

POLYQUATERNIUM-58

4.0

Polyquaternium-58 is a gentle conditioning polymer that smooths hair and reduces static without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-59

POLYQUATERNIUM-59

4.0

A gentle synthetic polymer that smooths hair and reduces frizz without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-61

Polyquaternium-61

4.0

Polyquaternium-61 is a gentle conditioning polymer that reduces static and improves feel in hair and skin products.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-63

Polyquaternium-63

4.0

A gentle synthetic polymer that helps hair feel soft, reduces frizz, and protects color without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-65

Polyquaternium-65

4.0

Polyquaternium-65 is a gentle conditioning polymer that smooths hair and skin without heavy buildup, making it a popular choice for sensitive scalps and daily use.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-68

POLYQUATERNIUM-68

4.0

A gentle synthetic polymer that smooths hair cuticles and reduces static without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Antistatic agent

Polyquaternium-7

POLYQUATERNIUM-7

4.0

Polyquaternium-7 is a gentle conditioning polymer that helps reduce frizz and static in hair without heavy buildup, making it a common choice in shampoos and conditioners.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-70

Polyquaternium-70

4.0

Polyquaternium-70 is a gentle, film-forming polymer that smooths hair and skin without heavy buildup, making it a solid choice for sensitive scalps and dry hair.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-75

Polyquaternium-75

4.0

Polyquaternium-75 is a gentle, film-forming polymer that smooths hair cuticles and reduces flyaways without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Antistatic agent

Polyquaternium-77

Polyquaternium-77

4.0

A gentle detangling polymer that smooths hair without the heavy feel of older polyquaterniums.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-78

Polyquaternium-78

4.0

A gentle, modern conditioning polymer that smooths hair and reduces static without the heavy feel of older polyquaterniums.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-79

Polyquaternium-79

4.0

A gentle synthetic polymer that smooths hair cuticles and reduces static, making hair easier to manage.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Antistatic agent

Polyquaternium-80

Polyquaternium-80

4.0

Polyquaternium-80 is a gentle conditioning polymer that reduces flyaways and improves wet combing without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-82

POLYQUATERNIUM-82

4.0

A gentle synthetic polymer that smooths hair cuticles and reduces frizz without the heavy feel of some silicones.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-87

Polyquaternium-87

4.0

Polyquaternium-87 is a gentle synthetic polymer that smooths hair cuticles and reduces frizz without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-89

Polyquaternium-89

4.0

Polyquaternium-89 is a gentle, film-forming polymer that smooths hair and reduces flyaways without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-92

Polyquaternium-92

4.0

A gentle, lightweight conditioning polymer that smooths hair and fights frizz without buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-94

Polyquaternium-94

4.0

Polyquaternium-94 is a gentle synthetic polymer that coats hair to reduce frizz and improve manageability without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-95

Polyquaternium-95

4.0

Polyquaternium-95 is a gentle, film-forming polymer that smooths hair cuticles and reduces static without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Film Former

Polyquaternium-98

Polyquaternium-98

4.0

Polyquaternium-98 is a gentle, film-forming polymer that smooths hair and skin without heavy buildup, making it a good choice for sensitive scalps and fine hair.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Skin conditioning agent

Potassium Tyrosyl Histidine Olivamide

Potassium Tyrosyl Histidine Olivamide

4.0

A gentle, olive-derived peptide that helps strengthen the skin barrier and improve hydration without irritation.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
Read ingredient review

Film Former

PPG-1 Hydroxypropyltrimonium Cassia

PPG-1 HYDROXYPROPYLTRIMONIUM CASSIA

4.0

A gentle, plant-derived conditioning ingredient that helps detangle hair and improve manageability without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Skin conditioning agent

PPG-2 Arginine

PPG-2 Arginine

3.8

PPG-2 Arginine is a gentle, modified amino acid that helps keep skin and hair soft, smooth, and hydrated without irritation.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
Read ingredient review

Skin conditioning agent

PPG-20 Tocophereth-5

PPG-20 Tocophereth-5

4.0

A gentle, multi-tasking ingredient that moisturizes and provides antioxidant benefits without common irritation.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
Read ingredient review

Antistatic agent

PPG-25 Diethylmonium Chloride

PPG-25 Diethylmonium Chloride

4.0

A gentle synthetic conditioning agent that helps reduce static and smooth hair without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Antistatic Agent

PPG-9 Diethylmonium Chloride

PPG-9 Diethylmonium Chloride

3.8

A synthetic conditioning ingredient that helps reduce static and soften hair, but may cause buildup with frequent use.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Conditioning Agent

Prolinamidoethyl Imidazole

Prolinamidoethyl Imidazole

3.5

A gentle synthetic ingredient that may help condition skin and hair while offering antioxidant support, but research is still limited.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
Read ingredient review

Hair conditioning agent

Propyltrimonium Hydrolyzed Wheat Protein

PROPYLTRIMONIUM HYDROLYZED WHEAT PROTEIN

4.0

A gentle, positively charged wheat protein that coats hair to improve softness, manageability, and shine without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyhaircareconditioning agent
Read ingredient review

Skin conditioner

Pumpkin Phytoplacenta Extract

Cucurbita Pepo (Pumpkin) Phytoplacenta Extract

3.8

A gentle, plant-based extract that may support skin firmness and hydration, but lacks robust clinical evidence.

Irritation

low

Source

natural

beautyskincareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-16

Quaternium-16

3.8

A synthetic conditioning ingredient that reduces static and softens hair, but may cause buildup with frequent use.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-18 Methosulfate

Quaternium-18 Methosulfate

3.8

A synthetic conditioning ingredient that helps reduce static and improve manageability, but may be too heavy for fine or acne-prone skin.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-22

Quaternium-22

4.0

Quaternium-22 is a gentle conditioning ingredient that reduces static and improves feel in hair and skin products, with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-30

Quaternium-30

3.8

Quaternium-30 is a synthetic conditioning ingredient that helps reduce frizz and static in hair while adding a silky feel, but it may not suit those avoiding silicones or heavy polymers.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-45

Quaternium-45

3.8

Quaternium-45 is a synthetic conditioning ingredient that reduces static and improves manageability in hair products, with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-51

Quaternium-51

3.8

Quaternium-51 is a gentle synthetic conditioner that helps reduce static and improve the feel of hair and skin without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-52

Quaternium-52

3.8

Quaternium-52 is a gentle synthetic conditioner that reduces frizz and static without heavy buildup, but it offers no active skincare benefits.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic agent

Quaternium-70

Quaternium-70

3.5

Quaternium-70 is a synthetic conditioning ingredient that helps reduce frizz and static in hair, but it may not suit those with very fine or easily weighed-down hair.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-71

Quaternium-71

3.8

Quaternium-71 is a gentle synthetic conditioner that helps detangle hair and soften skin without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-72

Quaternium-72

3.5

Quaternium-72 is a synthetic conditioning ingredient that helps reduce static and improve manageability in hair products, with a low risk of irritation for most users.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-75

Quaternium-75

4.0

A gentle, plant-derived conditioning agent that reduces frizz and static without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyhaircareconditioning agent
Read ingredient review