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

Antioxidant

Rowan Berry Extract

SORBUS AUCUPARIA FRUIT EXTRACT

4.0

A gentle, antioxidant-packed fruit extract that helps protect skin from environmental stress and may support a more even tone.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rowan Bud Extract

Pyrus Sorbus Bud Extract

3.8

A gentle botanical extract with antioxidant potential, but research on its specific benefits for skin is still limited.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rowan Fruit and Leaf Extract

SORBUS AUCUPARIA FRUIT/LEAF EXTRACT

4.0

Rowan fruit and leaf extract is a gentle, antioxidant-rich botanical that may help protect skin from environmental stress while providing mild soothing benefits.

Irritation

low

Source

natural

beautyskincareantioxidant
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Emollient

Rowan Seed Oil

SORBUS AUCUPARIA SEED OIL

4.0

A gentle, nutrient-rich oil that softens skin and supports barrier function, though research is still limited.

Irritation

low

Source

natural

beautyskincareemollient
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Antioxidant

Royal Fern Leaf Extract

Osmunda regalis leaf extract

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Humectant

Royal Jelly

ROYAL JELLY

3.8

Royal jelly is a natural humectant that helps hydrate and soothe skin, but its benefits are modest and not backed by strong clinical evidence.

Irritation

low

Source

natural

beautyskincarehumectant
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Skin conditioning agent

Royal Jelly Ferment Filtrate

LACTOBACILLUS/ROYAL JELLY FERMENT FILTRATE

4.0

A gentle fermented ingredient that may help soothe and condition the skin, though research is still limited.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Humectant

Royal Jelly Water

Water, Royal Jelly

3.8

Royal Jelly Water is a gentle, hydrating ingredient with potential soothing benefits, but its effects are not as well-studied as other humectants.

Irritation

low

Source

natural

beautyskincarehumectant
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Antioxidant

Rubia Cordifolia Root Powder

Rubia Cordifolia Root Powder

3.8

A gentle botanical powder with antioxidant and soothing potential, but research is limited and it may stain lighter fabrics or skin temporarily.

Irritation

low

Source

natural

beautyskincarebotanical
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Antioxidant

Rubia Cordifolia Stem Extract

RUBIA CORDIFOLIA STEM EXTRACT

3.8

A gentle botanical extract with antioxidant and soothing potential, but clinical evidence in skincare is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Rubus Chingii Fruit Extract

RUBUS CHINGII FRUIT EXTRACT

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rubusoside

RUBUSOSIDE

3.8

A gentle plant-derived antioxidant that may help calm redness and protect skin from environmental stress, though research is still early.

Irritation

low

Source

natural

beautyskincareantioxidant
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Abrasive

Ruby Extract

CORUNDUM (ALUMINUM OXIDE)

3.5

Ruby extract adds a touch of luxury to scrubs with gentle physical exfoliation, but its benefits are mostly aesthetic and not backed by strong research.

Irritation

moderate

Source

natural

beautyskincareexfoliant
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Abrasive

Ruby Powder

CORUNDUM (ALUMINUM OXIDE)

3.5

Ruby powder adds a gentle physical exfoliation and a subtle glow, but its benefits are mostly aesthetic and it may be too harsh for sensitive skin.

Irritation

moderate

Source

natural

beautyskincareexfoliant
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Antioxidant

Rudbeckia Hirta Seed Extract

RUDBECKIA HIRTA SEED EXTRACT

4.0

A gentle, plant-derived antioxidant that may help calm skin and protect against environmental stress, though research is still early.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rue Extract

Ruta Graveolens Leaf/Root/Stem Extract

3.5

Rue extract offers antioxidant potential but may cause skin irritation in sensitive individuals; use with caution.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
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Fragrance

Rue Herb Oil

Ruta Graveolens Herb Oil

2.8

Rue Herb Oil is a fragrant essential oil with limited skincare benefits and significant safety concerns, including phototoxicity and skin irritation, making it a risky choice for most everyday routines.

Irritation

high

Source

natural

beautyskincarefragrance
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Astringent

Rue Leaf/Stem Extract

RUTA GRAVEOLENS LEAF/STEM EXTRACT

3.5

Rue extract may offer astringent and soothing benefits, but its use is limited by potential skin irritation and lack of robust safety data.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
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Antioxidant

Rumex Extract

Rumex Pseudonatronatus Flower/Leaf/Stem Extract

3.8

A gentle plant extract with antioxidant and soothing potential, but research is limited and it's not a skincare powerhouse.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Runner Bean Seed Extract

Phaseolus coccineus seed 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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Anti-inflammatory

Ruscogenin

Ruscogenin

4.0

A gentle plant extract that helps calm redness and support microcirculation, often used in eye and anti-aging products.

Irritation

low

Source

natural

beautyskincareanti-inflammatory
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Antioxidant

Russelia Equisetiformis Extract

RUSSELIA EQUISETIFORMIS FLOWER/LEAF/STEM EXTRACT

3.5

A gentle botanical extract with antioxidant potential, but research on its specific benefits for skin is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Russula Virescens Extract

RUSSULA VIRESCENS EXTRACT

3.8

A mushroom extract with antioxidant potential, but research is limited—promising but not proven.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rutin

RUTIN

4.0

Rutin is a gentle plant antioxidant that helps defend skin against environmental damage and may support a more even skin tone.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rutinyl Succinate

Rutinyl Succinate

3.8

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

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Emollient

Ruttnera Lamellosa Oil

RUTTNERA LAMELLOSA OIL

4.0

A gentle, plant-based oil from microalgae that hydrates and supports the skin barrier without clogging pores.

Irritation

low

Source

natural

beautyskincareemollient
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Antioxidant

Rye Adventitious Root Extract

Secale Cereale Adventitious Root Extract

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Rye Callus Extract

Secale Cereale Callus Extract

4.0

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

Irritation

low

Source

biotech

beautyskincareantioxidant
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Skin conditioning

Rye Ferment Filtrate

LACTOBACILLUS/RYE FLOUR FERMENT FILTRATE

4.0

A gentle, fermented ingredient that may help strengthen the skin barrier and support a balanced microbiome.

Irritation

low

Source

biotech

beautyskincaresoothing
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Soothing Agent

Rye Phytoplacenta Extract

SECALE CEREALE PHYTOPLACENTA EXTRACT

3.8

A gentle, plant-derived extract that may help calm and condition the skin, but research is still limited.

Irritation

low

Source

natural

beautyskincaresoothing agent
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Soothing Agent

Rye Phytoplacenta Ferment Filtrate

SECALE CEREALE PHYTOPLACENTA CULTURE EXTRACT FILTRATE

3.8

A gentle, plant-based ferment that may help calm skin and fight free radicals, but research is still emerging.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Antioxidant

Rye Seed Extract

Secale Cereale Seed Extract

3.8

A gentle, plant-based extract that may help calm skin and provide antioxidant protection, though research is still limited.

Irritation

low

Source

natural

beautyskincareantioxidant
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Absorbent

Rye Seed Flour

Secale Cereale Seed Flour

3.8

A gentle, natural absorbent powder that helps control oil and add texture without common irritants found in some clay or synthetic powders.

Irritation

low

Source

natural

beautyskincareabsorbent
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Antioxidant

S-Allylcysteine

S-Allylcysteine

3.8

S-Allylcysteine is a gentle antioxidant from aged garlic that may help protect skin from oxidative stress and soothe inflammation, but research in topical cosmetics is still early.

Irritation

low

Source

natural

beautyskincareantioxidant
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Anti-aging agent

S-Bovine Oligopeptide-1

S-Bovine Oligopeptide-1

3.8

A synthetic peptide that may help firm skin and soften fine lines, but research is limited and mostly from ingredient suppliers.

Irritation

low

Source

synthetic

beautyskincarepeptide
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Antioxidant

S-Glyoxyloyl Acetyl Cysteine

S-GLYOXYLOYL ACETYL CYSTEINE

3.8

A promising but under-researched antioxidant that may help protect skin from environmental stress and support a more even tone.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Skin conditioning agent

S-HIV-1 Oligopeptide-1

S-HIV-1 Oligopeptide-1

2.5

An experimental peptide with uncertain cosmetic benefits and no established safety profile for topical use.

Irritation

low

Source

synthetic

beautyskincarepeptide
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Antioxidant

S-Lactoylglutathione

S-Lactoylglutathione

4.0

S-Lactoylglutathione is a gentle antioxidant that may help brighten skin and protect against environmental stress, but research is still early.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Anti-aging agent

S-Mussel Oligopeptide-1

S-MUSSEL OLIGOPEPTIDE-1

3.8

A synthetic peptide that may help firm and smooth skin, but research is still early and results vary.

Irritation

low

Source

synthetic

beautyskincarepeptide
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Anti-Aging Agent

S-Mussel Oligopeptide-2

S-MUSSEL OLIGOPEPTIDE-2

3.8

A marine-inspired peptide that may help firm skin and reduce fine lines, but research is still early.

Irritation

low

Source

synthetic

beautyskincareanti-aging
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Anti-aging agent

S-Mussel Polypeptide-1

S-MUSSEL POLYPEPTIDE-1

3.8

A synthetic peptide that may help firm and smooth skin, but research is still early and benefits are not yet proven in large human studies.

Irritation

low

Source

synthetic

beautyskincarepeptide
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Antioxidant

S-Olivoyl Glutathione

S-Olivoyl Glutathione

4.0

A stabilized, oil-friendly form of glutathione that may help brighten skin and fight oxidative stress, though human studies are still limited.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Antioxidant

S-Palmitoyl Glutathione

S-Palmitoyl Glutathione

4.0

A fat-soluble form of glutathione that may help brighten skin and fight oxidative stress, but human evidence is still limited.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Anti-aging agent

S-Rice Oligopeptide-1

S-Rice Oligopeptide-1

3.8

A gentle peptide that may support collagen and skin firmness, but research is still early and benefits are not guaranteed.

Irritation

low

Source

semi-synthetic

beautyskincarepeptide
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Antioxidant

S-Stearoyl Glutathione

S-Stearoyl Glutathione

4.0

A promising antioxidant that may help brighten skin and fight free radicals, but research is still limited compared to more established ingredients.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
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Skin conditioning agent

S-Syringoyl Acetyl Methyl Cysteinate

S-Syringoyl Acetyl Methyl Cysteinate

3.8

A gentle, synthetic amino acid derivative that may help calm skin and support barrier repair, though research is still emerging.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
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Anti-wrinkle agent

S-Viper Cysteine-Rich Venom Protein

S-VIPER CYSTEINE-RICH VENOM PROTEIN

3.5

A synthetic peptide that mimics snake venom to temporarily relax expression lines, but evidence is still emerging and results are subtle.

Irritation

low

Source

synthetic

beautyskincarepeptide
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Soothing Agent

Sabatia Angularis Extract

SABATIA ANGULARIS EXTRACT

3.8

A gentle botanical extract with potential soothing and antioxidant benefits, though research is limited and it is not a standout ingredient on its own.

Irritation

low

Source

natural

beautyskincarebotanical
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Humectant

Saccharide Isomerate

Saccharide Isomerate

4.5

A gentle, plant-derived humectant that provides deep, lasting hydration by binding to the skin's surface.

Irritation

low

Source

natural

beautyskincarehumectant
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Flavoring Agent

Saccharin

Saccharin

2.5

Saccharin is a non-nutritive sweetener used in cosmetics to improve taste, but it offers no skincare benefits and is unnecessary for most products.

Irritation

low

Source

synthetic

beautyskincareflavoring agent
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Humectant

Saccharomyces Lysate Extract

Saccharomyces Lysate Extract

4.0

A gentle, fermented yeast extract that hydrates and supports skin barrier health, ideal for sensitive and dry skin types.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Saccharomyces Rice Ferment Filtrate

SACCHAROMYCES/HYDROLYZED GERMINATED RICE GRAIN FERMENT FILTRATE

4.0

A gentle fermented rice ingredient that helps soften skin and improve texture without harsh exfoliation.

Irritation

low

Source

biotech

beautyskincarehumectantexfoliant
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Antioxidant

Saccharomyces/Gold Ferment

SACCHAROMYCES/GOLD FERMENT

3.8

A trendy fermented gold ingredient that may offer antioxidant benefits, but research is limited and its high cost doesn't guarantee superior results over simpler antioxidants.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Humectant

Saccharomyces/Magnesium Ferment

SACCHAROMYCES/MAGNESIUM FERMENT

4.0

A gentle, biotech-derived ferment that pairs yeast metabolites with magnesium to support hydration and a healthy-looking skin barrier.

Irritation

low

Source

biotech

beautyskincarehumectantconditioning agent
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