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

Hair conditioning agent

Quaternium-79 Hydrolyzed Keratin

Quaternium-79 Hydrolyzed Keratin

4.0

A gentle, protein-based conditioner that helps strengthen hair and reduce frizz without weighing it down.

Irritation

low

Source

semi-synthetic

beautyhaircareconditioning agent
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Hair Conditioning Agent

Quaternium-79 Hydrolyzed Milk Protein

QUATERNIUM-79 HYDROLYZED MILK PROTEIN

3.8

A gentle conditioning ingredient that makes hair and skin feel softer and more manageable without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Hair Conditioner

Quaternium-79 Hydrolyzed Silk

Quaternium-79 Hydrolyzed Silk

4.0

A gentle conditioning ingredient that helps hair feel soft and smooth while reducing static and flyaways.

Irritation

low

Source

semi-synthetic

beautyskincarehaircare
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Antistatic Agent

Quaternium-8

Quaternium-8

3.5

A gentle synthetic conditioner that helps detangle hair and reduce flyaways, but offers no long-term repair.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antistatic Agent

Quaternium-80

Quaternium-80

3.8

Quaternium-80 is a gentle conditioning ingredient that reduces static and softens hair, but it may not suit very sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircare
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Antistatic Agent

Quaternium-81

Quaternium-81

3.5

A synthetic conditioning agent that helps reduce frizz and static, but offers limited skin benefits beyond temporary smoothness.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antistatic Agent

Quaternium-82

Quaternium-82

3.5

Quaternium-82 is a synthetic conditioning ingredient that helps reduce static and improve hair feel, but it may build up on fine or low-porosity hair over time.

Irritation

low

Source

synthetic

beautyskincarehair careconditioning agent
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Antistatic Agent

Quaternium-83

Quaternium-83

3.5

Quaternium-83 is a synthetic conditioning agent that helps reduce static and improve manageability in hair products, with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antistatic Agent

Quaternium-84

Quaternium-84

3.5

A synthetic conditioning ingredient that helps reduce flyaways and static in hair, generally considered safe for most users.

Irritation

low

Source

synthetic

beautyskincarehair careconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-85

Quaternium-85

3.8

A gentle synthetic conditioner that smooths hair and reduces static, but may build up with frequent use.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
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Antistatic Agent

Quaternium-86

Quaternium-86

3.5

Quaternium-86 is a synthetic conditioning ingredient that helps reduce static and improve manageability in hair products, but it may cause buildup with frequent use.

Irritation

low

Source

synthetic

beautyskincarehaircare
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Antistatic Agent

Quaternium-87

Quaternium-87

3.5

Quaternium-87 is a synthetic conditioning ingredient that helps reduce static and soften hair, but it may not suit very sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antistatic Agent

Quaternium-88

Quaternium-88

4.0

Quaternium-88 is a gentle conditioning polymer that smooths hair and skin without heavy buildup, making it a popular choice for sensitive scalps and fine hair.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
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Antistatic Agent

Quaternium-89

Quaternium-89

4.0

A gentle synthetic conditioning agent that reduces frizz and static without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
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Antistatic Agent

Quaternium-90

Quaternium-90

3.5

Quaternium-90 is a synthetic conditioning ingredient that helps reduce static and improve manageability in hair products, but it may not suit very sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Viscosity Controlling

Quaternium-90 Bentonite

Quaternium-90 Bentonite

3.8

A gentle clay derivative that improves product feel and stability, but offers no direct skin benefit.

Irritation

low

Source

semi-synthetic

beautyskincarethickener
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Viscosity controlling agent

Quaternium-90 Montmorillonite

Quaternium-90 Montmorillonite

3.8

A modified clay that helps control oil and improve product feel, generally safe but not well-studied in long-term use.

Irritation

low

Source

semi-synthetic

beautyskincarehaircare
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Viscosity Controlling

Quaternium-90 Sepiolite

QUATERNIUM-90 SEPIOLITE

3.8

A gentle clay-derived thickener that improves product feel without common irritation concerns.

Irritation

low

Source

semi-synthetic

beautyskincaretexturizer
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Antistatic Agent

Quaternium-91

Quaternium-91

3.8

A gentle synthetic conditioner that helps detangle hair and reduce flyaways without heavy buildup.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-92

Quaternium-92

3.8

A synthetic conditioning ingredient that helps detangle hair and reduce frizz with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antistatic Agent

Quaternium-93

Quaternium-93

3.5

Quaternium-93 is a synthetic conditioning ingredient that helps reduce frizz and static in hair, but it may not suit those with very sensitive scalps.

Irritation

low

Source

synthetic

beautyskincarehaircare
Read ingredient review

Antistatic Agent

Quaternium-95

Quaternium-95

3.8

Quaternium-95 is a synthetic conditioning ingredient that helps detangle and soften hair with a low risk of irritation.

Irritation

low

Source

synthetic

beautyskincarehair care
Read ingredient review

Antistatic Agent

Quaternium-96

Quaternium-96

3.8

A synthetic conditioning agent that helps reduce static and improve the feel of hair and skin, generally well-tolerated but not a standout active.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antistatic Agent

Quaternium-97

Quaternium-97

3.8

Quaternium-97 is a synthetic conditioning ingredient that helps reduce frizz and static while making hair feel softer and easier to manage.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Antioxidant

Quebracho Ferment

ASPERGILLUS/ASPIDOSPERMA QUEBRACHO FERMENT

3.8

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

Irritation

low

Source

biotech

beautyskincareantioxidant
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Antioxidant

Quebracho Wood Extract

Schinopsis Quebracho-Colorado Wood Extract

4.0

A natural antioxidant extract that helps protect skin from environmental stress and may support a more even skin tone.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercetagetin

Quercetagetin

4.0

Quercetagetin is a gentle antioxidant that helps protect skin from environmental stress, but research on its cosmetic benefits is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercetin

QUERCETIN

4.0

Quercetin is a potent plant antioxidant that helps defend skin against pollution and UV damage while supporting a calmer, more even complexion.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercetin Caprylate

Quercetin Caprylate

4.0

A stabilized, oil-friendly version of quercetin that offers antioxidant protection with better skin absorption.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Exfoliant

Quercus Acutissima Fruit Powder

Quercus Acutissima Fruit Powder

3.8

A gentle, natural exfoliating powder from oak fruit, best for those seeking mild physical exfoliation with antioxidant benefits.

Irritation

low

Source

natural

beautyskincareexfoliant
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Antioxidant

Quercus Glauca Seed Extract

Quercus Glauca Seed Extract

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercus Glauca Stem Extract

QUERCUS GLAUCA STEM EXTRACT

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercus semecarpifolia Bark Extract

QUERCUS SEMECARPIFOLIA BARK EXTRACT

3.8

A gentle, antioxidant-rich bark extract that may help calm skin and protect against environmental stress, though research is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercus Serrata Extract

Quercus Serrata Extract

4.0

A gentle, plant-based antioxidant that helps protect skin from environmental stress while offering soothing benefits.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quercus Serrata Seed Extract

Quercus Serrata Seed Extract

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Surfactant

Quillaja Bark Extract

Quillaja Saponaria Bark Extract

4.0

A gentle, plant-derived surfactant that creates a mild foam and cleanses without stripping the skin's natural moisture barrier.

Irritation

low

Source

natural

beautyskincarecleansing agent
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Antioxidant

Quince Flower Extract

Pyrus Cydonia Flower Extract

3.8

Quince flower extract is a mild botanical with antioxidant potential, but research is limited and it's mainly used as a gentle skin conditioner.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quince Fruit Extract

Pyrus Cydonia Fruit Extract

4.0

A gentle fruit extract that may help protect skin from environmental stress and provide light hydration.

Irritation

low

Source

natural

beautyskincareantioxidant
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Humectant

Quince Fruit Juice

Pyrus Cydonia Fruit Juice

3.8

Quince fruit juice is a gentle, hydrating ingredient with antioxidant properties, but research on its skincare benefits is still emerging.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Quince Fruit Water

Cydonia Oblonga Fruit Water

4.0

Quince fruit water is a mild, hydrating botanical water that can soothe and lightly moisturize skin, but it lacks strong clinical evidence for dramatic effects.

Irritation

low

Source

natural

beautyskincarehumectantsoothing
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Emollient

Quince Peel/Fruit Wax

Pyrus Cydonia Peel/Fruit Wax

4.0

A gentle, plant-derived wax that helps lock in moisture and create a smooth, protective layer on skin.

Irritation

low

Source

natural

beautyskincareemollient
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Humectant

Quince Seed Extract

Pyrus Cydonia Seed Extract

4.0

A gentle, plant-based hydrator that forms a light, soothing film on the skin to help lock in moisture.

Irritation

low

Source

natural

beautyskincarehumectant
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Emollient

Quince Seed Oil

Pyrus Cydonia Seed Oil

4.0

Quince seed oil is a gentle, nutrient-rich emollient that hydrates and softens skin without clogging pores.

Irritation

low

Source

natural

beautyskincareemollient
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Exfoliant

Quinic Acid

Quinic Acid

4.0

A gentle, plant-derived AHA that exfoliates and hydrates without the sting of stronger acids, making it a good option for sensitive skin.

Irritation

low

Source

natural

beautyskincareexfoliant
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Antimicrobial

Quinine

QUININE

3.5

Quinine can help calm inflammation and fight microbes, but it may irritate sensitive skin and is not a proven anti-aging ingredient.

Irritation

moderate

Source

natural

beautyskincareantimicrobial
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Humectant

Quinoa Ferment Filtrate

LACTOBACILLUS/QUINOA FERMENT EXTRACT FILTRATE

4.0

A gentle, probiotic-derived ingredient that may help strengthen the skin barrier and improve hydration, though research is still emerging.

Irritation

low

Source

biotech

beautyskincarehumectant
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Antioxidant

Quinoa Flower/Leaf Extract

Chenopodium Quinoa Flower/Leaf Extract

3.8

A gentle, antioxidant-rich plant extract that may help calm and protect skin, though research is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Quinoa Husk Extract

Chenopodium Quinoa Husk Extract

4.0

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Exfoliant

Quinoa Husk Powder

Chenopodium Quinoa Husk Powder

3.8

A gentle, natural exfoliant from quinoa husks that buffs away dead skin without harsh microbeads.

Irritation

low

Source

natural

beautyskincareexfoliant
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Soothing agent

Quinoa Seed Extract

Chenopodium Quinoa Seed Extract

4.0

Quinoa Seed Extract is a gentle, plant-based ingredient that helps soothe and hydrate the skin, making it a good choice for sensitive or dry skin types.

Irritation

low

Source

natural

beautyskincaresoothing agent
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Emollient

Quinoa Seed Oil

Chenopodium Quinoa Seed Oil

4.0

Quinoa seed oil is a gentle, nutrient-dense emollient that helps soften and protect the skin without clogging pores.

Irritation

low

Source

natural

beautyskincareemollient
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Emollient

Quinoa Seed Oil Ethyl Esters

Chenopodium Quinoa Seed Oil Ethyl Esters

4.0

A lightweight, plant-derived emollient that hydrates without clogging pores, ideal for sensitive and oily skin types.

Irritation

low

Source

semi-synthetic

beautyskincareemollient
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Soothing Agent

Quinoa Seedcake Extract

Chenopodium Quinoa Seedcake Extract

4.0

Quinoa Seedcake Extract is a gentle, plant-based ingredient that helps calm and condition the skin, though research on its specific benefits is still emerging.

Irritation

low

Source

natural

beautyskincaresoothing agent
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