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 1,094
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

Humectant

PPG-25 Glycereth-22

PPG-25 Glycereth-22

4.0

A gentle, water-binding ingredient that helps keep skin hydrated and improves product feel without common irritation.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

PPG-25 Methyl Glucose Ether

PPG-25 Methyl Glucose Ether

4.0

A gentle, synthetic humectant that helps hydrate the skin and improve product feel without common irritation concerns.

Irritation

low

Source

synthetic

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Humectant

PPG-25 Sorbitol

PPG-25 SORBITOL

4.0

A gentle, synthetic humectant that draws moisture to the skin without common irritation.

Irritation

low

Source

synthetic

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Humectant

PPG-27 Glyceryl Ether

PPG-27 Glyceryl Ether

4.0

A gentle synthetic humectant that hydrates the skin and improves the feel of cosmetic formulas without common irritation.

Irritation

low

Source

synthetic

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Humectant

PPG-3 Glyceryl Ether

PPG-3 Glyceryl Ether

4.0

A gentle, synthetic humectant that draws moisture into the skin without the sticky feel of glycerin.

Irritation

low

Source

synthetic

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Humectant

PPG-33 Sorbitol

PPG-33 Sorbitol

4.0

A gentle, water-attracting ingredient that helps keep skin hydrated without clogging pores or causing irritation.

Irritation

low

Source

semi-synthetic

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Humectant

PPG-4 Diglyceryl Ether

PPG-4 Diglyceryl Ether

4.0

A gentle, synthetic humectant that pulls water into the skin and improves the feel of your products without common irritation.

Irritation

low

Source

synthetic

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Humectant

PPG-41 Sorbitol

PPG-41 Sorbitol

4.0

A gentle, semi-synthetic humectant that helps hydrate the skin without clogging pores, making it a good option for most skin types.

Irritation

low

Source

semi-synthetic

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Humectant

PPG-50 Glyceryl Ether

PPG-50 Glyceryl Ether

4.0

A gentle, synthetic humectant that draws moisture into the skin without the sticky feel of glycerin.

Irritation

low

Source

synthetic

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Humectant

PPG-55 Glyceryl Ether

PPG-55 Glyceryl Ether

4.0

A gentle, synthetic humectant that draws moisture to the skin and helps other ingredients absorb better.

Irritation

low

Source

synthetic

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Humectant

PPG-6 Glyceryl Ether

PPG-6 Glyceryl Ether

4.0

A gentle, synthetic humectant that draws moisture to the skin without the stickiness of glycerin.

Irritation

low

Source

synthetic

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Humectant

PPG-66-Glycereth-12

PPG-66-Glycereth-12

4.0

A gentle, synthetic humectant that helps hydrate skin and improve product feel without common irritation risks.

Irritation

low

Source

synthetic

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Humectant

PPG-67 Glyceryl Ether

PPG-67 Glyceryl Ether

4.0

A gentle, synthetic humectant that draws moisture to the skin without the sticky feel of glycerin.

Irritation

low

Source

synthetic

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Humectant

PPG-69

PPG-69

3.8

PPG-69 is a gentle synthetic humectant that helps keep skin hydrated without clogging pores, but it offers no unique benefits over more common alternatives.

Irritation

low

Source

synthetic

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Humectant

PPG-70 Glyceryl Ether

PPG-70 Glyceryl Ether

4.0

A gentle, synthetic humectant that draws moisture into the skin without the stickiness of glycerin.

Irritation

low

Source

synthetic

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Humectant

PPG-75-PEG-300 Hexylene Glycol

PPG-75-PEG-300 Hexylene Glycol

3.8

A synthetic humectant that helps keep skin hydrated and improves product texture, but offers no unique benefits over more common alternatives.

Irritation

low

Source

synthetic

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Humectant

PPG-8 Glyceryl Ether

PPG-8 Glyceryl Ether

4.0

A gentle, synthetic humectant that attracts moisture to the skin without the sticky feel of glycerin.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

PPG-9 Glyceryl Ether

PPG-9 Glyceryl Ether

4.0

A gentle, synthetic humectant that attracts moisture to the skin without common irritation or clogging.

Irritation

low

Source

synthetic

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Humectant

Prickly Pear Fruit Juice

Opuntia Phaeacantha Fruit Juice

4.0

A gentle, water-based extract that provides hydration and antioxidant protection, especially suitable for dry or sensitive skin.

Irritation

low

Source

natural

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Humectant

Prickly Pear Fruit Water

Opuntia Ficus-Indica Fruit Water

4.0

A gentle, antioxidant-rich water that hydrates and soothes the skin without clogging pores.

Irritation

low

Source

natural

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Humectant

Prickly Pear Leaf Extract

Opuntia Vulgaris Leaf Extract

4.0

A gentle, plant-based hydrator with antioxidant benefits, ideal for dry or sensitive skin types.

Irritation

low

Source

natural

beautyskincarehumectantantioxidant
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Humectant

Prickly Pear Leaf Juice

Opuntia Robusta Leaf Juice

4.0

A gentle, water-rich humectant that hydrates and soothes skin with antioxidant support, ideal for sensitive or dehydrated skin types.

Irritation

low

Source

natural

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Humectant

Prickly Pear Stem Water

Opuntia Ficus-Indica Stem Water

4.0

A gentle, antioxidant-rich plant water that hydrates and soothes skin without clogging pores.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Proline

PROLINE

4.0

Proline is a gentle, hydrating amino acid that supports skin structure and moisture retention.

Irritation

low

Source

natural

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Humectant

Propanediol

Propanediol

4.5

Propanediol is a gentle, plant-based alternative to propylene glycol that hydrates the skin and helps other ingredients work better.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Propoxypropanediol

PROPOXYPROPANEDIOL

4.0

A gentle synthetic humectant that helps hydrate skin and improve product feel without common irritation.

Irritation

low

Source

synthetic

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Humectant

Propylene Glycol

Propylene Glycol

3.8

Propylene glycol is a widely used, effective humectant and solvent, but it can be irritating for sensitive skin at high concentrations.

Irritation

moderate

Source

synthetic

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Humectant

Propylene Glycol Citrate

Propylene Glycol Citrate

4.0

A gentle, water-attracting ingredient that helps keep skin hydrated and balanced without common irritations.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
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Humectant

Protea Repens Flower Nectar

PROTEA REPENS FLOWER NECTAR

3.8

A gentle, natural humectant from South African protea flowers that helps hydrate skin, but research on its specific benefits is still limited.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Prunus Triloba Fruit Water

PRUNUS TRILOBA FRUIT WATER

3.8

A gentle, water-like ingredient from flowering plum fruit that adds light hydration and a touch of antioxidants, but lacks strong clinical backing.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Psicose

PSICOSE

4.0

Psicose is a gentle, natural humectant that helps hydrate skin and may offer antioxidant benefits, though research in cosmetics is still limited.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Pullulan Ferment Filtrate

AUREOBASIDIUM PULLULANS/OLIVE OIL FERMENT FILTRATE

4.0

A gentle, fermented ingredient that helps hydrate and soothe the skin while supporting a healthy moisture barrier.

Irritation

low

Source

biotech

beautyskincarehumectantsoothing
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Humectant

Pulvinate Algae Extract

Pulvinata Extract

3.8

A gentle, hydrating algae extract that may help soothe and moisturize skin, but research is still limited.

Irritation

low

Source

natural

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Humectant

Pumpkin Fruit Extract with Beta-Glucan

Cucurbita Pepo (Pumpkin) Fruit Extract, Beta-Glucan

4.0

A gentle, hydrating blend that combines pumpkin's natural enzymes with beta-glucan's soothing power—great for a brighter, smoother complexion without harsh irritation.

Irritation

low

Source

natural

beautyskincarehumectantexfoliant
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Humectant

Pumpkin Fruit Juice

CUCURBITA MAXIMA FRUIT JUICE

3.8

Pumpkin fruit juice is a gentle, water-based hydrator with mild antioxidant benefits, but its effects are mostly from its water content and trace nutrients.

Irritation

low

Source

natural

beautyskincarehumectant
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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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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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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

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Humectant

R-Saccharomyces Polypeptide-1

R-SACCHAROMYCES POLYPEPTIDE-1

4.0

A gentle, yeast-derived peptide that helps hydrate and support the skin barrier, but research is still emerging.

Irritation

low

Source

biotech

beautyskincarehumectantconditioning agent
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Humectant

Raffinose

RAFFINOSE

4.0

Raffinose is a gentle, plant-derived sugar that hydrates the skin and feeds beneficial bacteria, making it a smart choice for sensitive or microbiome-focused routines.

Irritation

low

Source

natural

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Humectant

Raffinose Oleate

RAFFINOSE OLEATE

4.0

Raffinose Oleate is a gentle, sugar-based ingredient that hydrates and soothes the skin, making it a promising option for sensitive or dry skin types.

Irritation

low

Source

semi-synthetic

beautyskincarehumectantemollient
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Humectant

Red Algae Callus Extract

Botryocladia Adhaerens Callus Extract

4.0

A gentle, hydrating marine extract that may help soothe and protect the skin, though research is still emerging.

Irritation

low

Source

natural

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Humectant

Red Algae Complex Extract

Hydrolyzed Gelidium Elegans/Gracilaria Vermiculophylla/Gracilaria Gigas/Pterocladiella Capillacea/Ahnfeltia Plicata Extract

4.0

A gentle, multi-species red algae extract that helps hydrate and soothe skin while forming a light protective film.

Irritation

low

Source

natural

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Humectant

Red Algae Extract

RHODOSORUS MARINUS EXTRACT

4.0

A gentle, hydrating algae extract that helps skin retain moisture and may calm irritation.

Irritation

low

Source

natural

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Humectant

Red Algae Extract Blend

Gigartina stellata/Kappaphycus alvarezii Extract

4.0

A gentle, hydrating seaweed extract that helps soothe skin and support moisture retention without irritation.

Irritation

low

Source

natural

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Humectant

Red Algae Powder

Porphyra Umbilicalis Powder

4.0

A gentle, ocean-derived powder that helps hydrate and calm the skin, making it a good choice for sensitive or dry skin types.

Irritation

low

Source

natural

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Humectant

Red Clover Water

TRIFOLIUM PRATENSE FLOWER/LEAF/STEM WATER

4.0

A mild, plant-based water that provides light hydration and soothing benefits, ideal for sensitive or dry skin types.

Irritation

low

Source

natural

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Humectant

Red Hot Poker Nectar

KNIPHOFIA UVARIA NECTAR

3.8

A gentle, plant-derived humectant that helps hydrate and calm the skin, though research on its benefits is still emerging.

Irritation

low

Source

natural

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Humectant

Rhamnose

RHAMNOSE

4.0

Rhamnose is a gentle plant-derived sugar that helps hydrate and lightly exfoliate skin, making it a good option for sensitive skin looking for mild renewal.

Irritation

low

Source

natural

beautyskincarehumectantexfoliant
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Humectant

Rhizopus/Saccharomyces Collagen Ferment Filtrate

RHIZOPUS/SACCHAROMYCES/COLLAGEN FERMENT FILTRATE

3.8

A fermented collagen ingredient that may help hydrate and condition skin, but research is still early and benefits are not yet proven in large human studies.

Irritation

low

Source

biotech

beautyskincarehumectantconditioning agent
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Humectant

Rhodella Violacea Extract

Rhodella Violacea Extract

4.0

A gentle, hydrating microalgae extract that helps skin retain moisture and defends against environmental stress.

Irritation

low

Source

natural

beautyskincarehumectantantioxidant
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Humectant

Rhubarb Fruit Water

Rheum Rhaponticum Fruit Water

3.8

A gentle, hydrating fruit water with mild antioxidant benefits, best for normal to dry skin types.

Irritation

low

Source

natural

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Humectant

Ribose

RIBOSE

3.5

Ribose is a gentle sugar molecule that may help energize skin cells and improve hydration, but human research is still limited.

Irritation

low

Source

natural

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