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

Hornbeam Extract

Carpinus Turczaninowii Extract

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Soothing Agent

Hornbeam Flower Extract

Carpinus Betulus Flower Extract

3.8

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

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Hornbeam Leaf Extract

CARPINUS CORDATA LEAF EXTRACT

3.5

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

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Horopito Flower/Leaf Extract

PSEUDOWINTERA COLORATA FLOWER/LEAF EXTRACT

3.8

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Horopito Leaf Extract

Pseudowintera colorata leaf extract

3.8

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

Irritation

low

Source

natural

beautyskincarebotanical extract
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Skin conditioning agent

Horse Adipose Stromal Cell Conditioned Media

HORSE ADIPOSE STROMAL CELL CONDITIONED MEDIA

3.0

A novel, lab-grown ingredient derived from horse stem cells that may support skin repair, but human research is very limited and it remains a niche, high-cost option.

Irritation

low

Source

biotech

beautyskincarebiotech
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Antioxidant

Horse Chestnut & Carrot & Fennel Extract

AESCULUS HIPPOCASTANUM BARK/DAUCUS CAROTA ROOT/FOENICULUM VULGARE FRUIT EXTRACT

3.8

A gentle botanical blend that offers antioxidant and soothing benefits, but its effectiveness depends on the specific formulation and concentration.

Irritation

low

Source

natural

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Soothing agent

Horse Chestnut Bark Extract

Aesculus Hippocastanum Bark Extract

4.0

Horse chestnut bark extract is a gentle botanical that may help calm skin and fight free radical damage, but its effectiveness in skincare is still being studied.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Horse Chestnut Bud Extract

AESCULUS HIPPOCASTANUM BUD EXTRACT

4.0

A gentle botanical extract that may help calm skin and fight free radical damage, but research is still emerging.

Irritation

low

Source

natural

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Soothing agent

Horse Chestnut Flower Extract

AESCULUS HIPPOCASTANUM/PAVIA FLOWER EXTRACT

4.0

A gentle, antioxidant-rich flower extract that may help calm skin and support a healthy-looking complexion.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Soothing Agent

Horse Chestnut Flower Water

AESCULUS HIPPOCASTANUM FLOWER WATER

3.8

A gentle, soothing floral water that may help calm irritated skin and provide mild astringent benefits, but research on its cosmetic efficacy is limited.

Irritation

low

Source

natural

beautyskincaresoothing
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Soothing Agent

Horse Chestnut Fruit Powder

AESCULUS HIPPOCASTANUM FRUIT POWDER

4.0

A gentle botanical powder that may help calm skin and support microcirculation, but raw forms can be irritating if not properly processed.

Irritation

low

Source

natural

beautyskincarebotanical
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Antioxidant

Horse Chestnut Leaf Extract

AESCULUS HIPPOCASTANUM LEAF EXTRACT

4.0

A gentle, plant-based extract that helps calm skin and fight free radical damage, but research is more focused on the seed than the leaf.

Irritation

low

Source

natural

beautyskincareantioxidant
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Emollient

Horse Fat

HORSE FAT

3.5

Horse fat is a traditional emollient that can soften skin, but it's not widely studied and may feel heavy for oily skin types.

Irritation

low

Source

natural

beautyskincareemollient
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Antioxidant

Horsemint Extract

Mentha Longifolia Flower/Leaf/Stem Extract

3.8

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

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Horseradish Peroxidase

Horseradish Peroxidase

3.8

Horseradish peroxidase is a natural enzyme that acts as a potent antioxidant, helping to neutralize free radicals and support skin resilience, though research in cosmetics is still emerging.

Irritation

low

Source

natural

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Antioxidant

Horseradish Root Extract

Cochlearia Armoracia Root Extract

3.8

Horseradish Root Extract offers antioxidant and antimicrobial benefits but can be irritating for sensitive skin, especially at high concentrations.

Irritation

moderate

Source

natural

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Soothing agent

Horsetail & Arnica & Chamomile Flower Extract

EQUISETUM ARVENSE/(ARNICA MONTANA/CHAMOMILLA RECUTITA) FLOWER EXTRACT

3.8

A gentle botanical blend that may help calm skin and provide antioxidant support, but individual plant sensitivities are possible.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Horsetail Extract

EQUISETUM HYEMALE LEAF/STEM EXTRACT

4.0

Horsetail extract is a gentle botanical rich in silica and antioxidants, often used to soothe and support skin barrier function.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Soothing Agent

Horsetail Juice

Equisetum Arvense Juice

3.8

A gentle, silica-rich plant juice that may help soothe skin and support a healthy-looking complexion, but its benefits are mostly anecdotal.

Irritation

low

Source

natural

beautyskincaresoothing
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Soothing agent

Horsetail Leaf Powder

EQUISETUM ARVENSE LEAF POWDER

3.8

A gentle, mineral-rich botanical powder that can help soothe skin and absorb excess oil, but its benefits are modest and best suited for combination or oily skin types.

Irritation

low

Source

natural

beautyskincarebotanical
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Soothing Agent

Horsetail Powder

Equisetum Arvense Powder

3.8

A gentle botanical powder that may help soothe skin and provide antioxidant benefits, but research is limited compared to more studied ingredients.

Irritation

low

Source

natural

beautyskincarebotanical
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Antioxidant

Hortonia Floribunda Leaf Extract

HORTONIA FLORIBUNDA LEAF EXTRACT

3.8

A gentle, plant-based antioxidant extract with limited but promising research; best for sensitive or environmentally stressed skin.

Irritation

low

Source

natural

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Antioxidant

Hosta Longipes Extract

Hosta Longipes Extract

3.8

A gentle plant extract with antioxidant potential, but research is limited and benefits are not yet well-established in human skin.

Irritation

low

Source

natural

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Soothing agent

Houttuynia & Volcanic Ash Ferment

Bacillus/Houttuynia Cordata Leaf Extract/Volcanic Ash Ferment Filtrate

4.0

A fermented botanical-mineral blend that may help calm irritation and provide antioxidant protection, though research is still emerging.

Irritation

low

Source

biotech

beautyskincaresoothing
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Soothing Agent

Houttuynia Cordata Extract

HOUTTUYNIA CORDATA FLOWER/LEAF EXTRACT

4.3

A gentle, plant-based ingredient that helps calm redness and provides antioxidant protection, ideal for sensitive or acne-prone skin.

Irritation

low

Source

natural

beautyskincarebotanical
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Soothing Agent

Houttuynia Cordata Powder

Houttuynia Cordata Powder

4.0

A gentle, plant-based powder that helps calm irritated skin and provides antioxidant protection, ideal for sensitive or acne-prone skin.

Irritation

low

Source

natural

beautyskincaresoothing agent
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Soothing Agent

Houttuynia Cordata Water

HOUTTUYNIA CORDATA FLOWER/LEAF/STEM WATER

4.2

A gentle, plant-derived water that helps calm irritation and provides antioxidant protection, ideal for sensitive or reactive skin.

Irritation

low

Source

natural

beautyskincaresoothing agent
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Soothing agent

Houttuynia Ferment Filtrate

LACTOBACILLUS/HOUTTUYNIA CORDATA LEAF EXTRACT FERMENT FILTRATE

4.0

A fermented botanical extract that may calm irritation and support a healthy skin barrier, though research is still early.

Irritation

low

Source

biotech

beautyskincaresoothing
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Antioxidant

Hoya Carnosa Extract

Hoya Carnosa Leaf/Stem Extract

3.5

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

Irritation

low

Source

natural

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Antioxidant

Hoya Carnosa Leaf Extract

HOYA CARNOSA LEAF EXTRACT

3.5

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

Irritation

low

Source

natural

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Antioxidant

Hoya Lacunosa Flower Extract

Hoya Lacunosa Flower Extract

3.5

A gentle, antioxidant-rich flower extract with limited research but a good safety profile for most skin types.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Huckleberry Extract

GAYLUSSACIA BACCATA EXTRACT

4.0

A gentle, antioxidant-rich botanical extract that may help protect skin from environmental stress and soothe minor irritation.

Irritation

low

Source

natural

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Skin conditioning agent

Human Buffy Coat Cell Conditioned Media

Human Buffy Coat Cell Conditioned Media

3.5

A cutting-edge, biotech-derived ingredient that delivers a cocktail of growth factors and cytokines to support skin repair, but human-source ingredients raise ethical and regulatory questions.

Irritation

low

Source

biotech

beautyskincareactive
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Humectant

Human Serum Albumin

HUMAN SERUM ALBUMIN

3.5

A human-derived protein that helps hydrate and temporarily plump the skin, but its benefits are not well-studied in cosmetics and sourcing raises ethical questions.

Irritation

low

Source

biotech

beautyskincarehumectant
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Antioxidant

Humic Acids

HUMIC ACIDS

3.8

Humic acids are gentle, antioxidant-rich compounds from ancient plant deposits that may help protect skin from environmental stress, but research is still early.

Irritation

low

Source

natural

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Antioxidant

Huon Pine Wood Extract

Dacrydium franklinii wood extract

3.8

A gentle, antioxidant-rich wood extract that may help protect skin from environmental stress, but research is limited.

Irritation

low

Source

natural

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Fragrance

Huon Pine Wood Oil

Dacrydium franklinii wood oil

3.5

Huon Pine Wood Oil adds a distinctive woody fragrance to products but has limited research on skin benefits and may cause irritation in sensitive individuals.

Irritation

moderate

Source

natural

beautyskincarefragrance
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Fragrance

Hyacinth Extract

Hyacinthus Orientalis Extract

3.5

Hyacinth Extract adds a pleasant floral scent to products but has limited proven skincare benefits beyond fragrance.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
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Antioxidant

Hyacinth Flower Extract

Hyacinthus Orientalis Flower Extract

3.5

A fragrant flower extract with mild antioxidant potential, but limited research and a moderate risk of skin irritation for sensitive types.

Irritation

moderate

Source

natural

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Antioxidant

Hyacinth Leaf Extract

Hyacinthus Orientalis Leaf Extract

3.5

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

Irritation

low

Source

natural

beautyskincareantioxidant
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Soothing Agent

Hyacinth Root Extract

Hyacinthus Orientalis Root Extract

3.8

A gentle botanical extract that may help calm redness and support the skin's moisture barrier, though research is still early.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Humectant

Hyaluronate RH-Oligopeptide-1

Hyaluronate RH-Oligopeptide-1

4.0

A modern hybrid of hyaluronic acid and a peptide that aims to hydrate and support skin firmness, but research is still limited.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Hyaluronic Acid

Sodium Hyaluronate

4.5

Hyaluronic acid is a superstar hydrator that holds up to 1,000 times its weight in water, making it a go-to for plumping and smoothing skin without clogging pores.

Irritation

low

Source

biotech

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Humectant

Hyaluronic Acid Crosspolymer

PEG-9 Diglycidyl Ether/Sodium Hyaluronate Crosspolymer

4.3

A more stable, longer-lasting version of hyaluronic acid that clings to the skin's surface for sustained hydration without the sticky feel.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
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Humectant

Hyaluronic Acid Ferment

Endomyces/Sodium Hyaluronate Ferment Filtrate

4.0

A fermented form of hyaluronic acid that may offer better absorption and hydration than standard hyaluronic acid.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Hyaluronic Acid Ferment Filtrate

SINOMONAS/HYALURONIC ACID FERMENT FILTRATE

4.0

A gentle, biotech-derived humectant that combines the hydrating power of hyaluronic acid with potential skin-soothing benefits from fermentation.

Irritation

low

Source

biotech

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Penetration enhancer

Hyaluronidase

Hyaluronidase

3.0

Hyaluronidase is an enzyme that breaks down hyaluronic acid in the skin, which can temporarily increase ingredient absorption but also risks irritation and moisture loss.

Irritation

moderate

Source

biotech

beautyskincareenzyme
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Antioxidant

Hybrid Cell Extract

GYNOSTEMMA PENTAPHYLLUM/LUFFA CYLINDRICA HYBRID CELL EXTRACT

3.8

A lab-grown hybrid plant cell extract that may offer antioxidant and soothing benefits, but research is still early.

Irritation

low

Source

biotech

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Soothing Agent

Hybrid Rose Flower Extract

Rosa Hybrid Flower Extract

4.0

A mild, fragrant rose extract that can help calm skin and provide antioxidant protection, but its benefits are largely from the whole flower complex rather than a single active.

Irritation

low

Source

natural

beautyskincarebotanical
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Emollient

Hydnocarpus Pentandrus Kernel Oil

HYDNOCARPUS PENTANDRUS KERNEL OIL

3.8

A traditional emollient oil with moisturizing benefits, but limited modern research and a moderate chance of clogging pores for some skin types.

Irritation

low

Source

natural

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Soothing agent

Hydrangea Flower Extract

DEFATTED HYDRANGEA MACROPHYLLA FLOWER

3.8

A mild botanical extract that may help calm skin and provide antioxidant support, but research is still early.

Irritation

low

Source

natural

beautyskincarebotanical
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Antioxidant

Hydrangea Flower/Fruit Extract

HYDRANGEA PANICULATA FLOWER/FRUIT EXTRACT

3.8

A gentle botanical extract that may help calm skin and fight free radicals, but research is still early.

Irritation

low

Source

natural

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Soothing Agent

Hydrangea Root Extract

Hydrangea Macrophylla Root Extract

3.8

A gentle botanical extract with antioxidant and soothing potential, though research on its cosmetic benefits is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Hydrangea Serrata Leaf Extract

Hydrangea Serrata Leaf Extract

4.0

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

Irritation

low

Source

natural

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Abrasive

Hydrated Silica

Hydrated Silica

4.2

Hydrated silica is a gentle, mineral-based abrasive that polishes teeth and exfoliates skin without harshness, but overuse can wear down enamel or irritate sensitive skin.

Irritation

low

Source

natural

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Fragrance Ingredient

Hydratropic Alcohol

Hydratropic Alcohol

3.5

Hydratropic alcohol adds a mild floral scent and helps preserve formulas, but it can be irritating for sensitive skin at higher concentrations.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
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