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

Skin conditioning agent

Myristoyl Hydrolyzed Collagen

Myristoyl Hydrolyzed Collagen

4.0

A gentle, fatty-acid-modified collagen that helps cleanse without stripping and leaves skin feeling soft.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Nonfat Dry Colostrum

Nonfat Dry Colostrum

3.8

A nutrient-dense ingredient that may support skin hydration and soothing, but human skincare research is still emerging.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Skin Conditioning Agent

Nonfat Dry Milk Extract

NONFAT DRY MILK EXTRACT

3.8

Nonfat dry milk extract is a gentle skin softener that provides light moisture and a soothing feel, but it offers limited active benefits compared to more concentrated dairy ingredients.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Humectant

Oat Protein Extract

Avena Sativa (Oat) Protein Extract

4.3

Oat protein extract is a gentle, moisturizing ingredient that helps soothe and protect the skin barrier, making it ideal for sensitive or dry skin types.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Antistatic Agent

Oleamidopropyl PG-Dimonium Chloride

Oleamidopropyl PG-Dimonium Chloride

4.0

A gentle conditioning ingredient that reduces static and softens hair and skin without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Skin conditioning

Oleoyl Hydrolyzed Collagen

OLEOYL HYDROLYZED COLLAGEN

3.8

A gentle, modified collagen that helps soften and smooth skin without clogging pores.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Oleoyl Tyrosine

Oleoyl Tyrosine

4.0

Oleoyl Tyrosine is a gentle, amino-acid-based ingredient that helps reinforce the skin barrier and improve hydration without irritation.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Oleyl Acetyl Glutaminate

Oleyl Acetyl Glutaminate

4.0

A mild, amino-acid-derived ingredient that conditions skin without irritation, making it a good choice for sensitive or dry skin types.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning

Olive Oil Amino Lipid Complex

OLIVE FRUIT OIL AMINOPROPANEDIOL AMIDES/ESTERS

4.0

A mild, olive-derived conditioning ingredient that helps soften skin and improve moisture retention without clogging pores.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Film Former

Olive Oil Wheat Protein

OLIVOYL HYDROLYZED WHEAT PROTEIN

4.0

A gentle, plant-derived conditioning ingredient that helps hair and skin feel soft and smooth without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Skin conditioning agent

Ostrich Egg Yolk Extract

OSTRICH EGG YOLK EXTRACT

3.5

A novel, nutrient-dense ingredient that may support skin hydration and barrier function, but clinical evidence is still limited.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Skin Conditioning

Oyster Extract

OSTREA EDULIS EXTRACT

3.8

Oyster extract is a mineral-rich ingredient that may help hydrate and soothe skin, but research on its cosmetic benefits is still emerging.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Antistatic Agent

Palmidopropyl Dimonium Chloride

Palmidoethyl Palmoylpropyl Dimonium Chloride

3.8

A gentle conditioning ingredient that reduces static and improves hair manageability, but its palm oil origin raises sustainability questions.

Irritation

low

Source

semi-synthetic

beautyhaircareconditioning agent
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Skin conditioning agent

Palmitoyl Alanine

Palmitoyl Alanine

4.0

A gentle, synthetic amino acid derivative that helps support the skin barrier and improve moisture retention without irritation.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Palmitoyl Carnitine

Palmitoyl Carnitine

3.8

Palmitoyl Carnitine is a gentle, fatty-acid-linked amino acid that may help soothe skin and support a healthy moisture barrier, though research is still early.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Palmitoyl Gold of Pleasure Amino Acids

Palmitoyl Gold of Pleasure Amino Acids

4.0

A gentle, barrier-friendly ingredient that combines fatty acids with plant amino acids to help skin feel smooth and hydrated.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Palmitoyl Mare Milk

Palmitoyl Mare Milk

3.5

A gentle, lipid-enriched mare milk derivative that may help moisturize and condition skin, but research is limited.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Skin conditioning agent

Palmitoyl Millet Amino Acids

Palmitoyl Millet Amino Acids

4.0

A gentle, plant-based conditioning ingredient that helps soften and smooth skin without irritation.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Palmitoyl Serine/Silk Amino Acids Methyl Esters

Palmitoyl Serine/Silk Amino Acids Methyl Esters

4.0

A gentle conditioning ingredient that may help support skin barrier function and improve texture, but research is limited compared to more established peptides.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Skin conditioning agent

Panthenyl Ethyl Ether Benzoate

Panthenyl Ethyl Ether Benzoate

3.8

A gentle, modified form of vitamin B5 that helps condition skin and hair with a silky feel, but research on this specific derivative is limited.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Conditioning Agent

Passion Fruit & Palm Oil Conditioning Complex

PASSIFLORA EDULIS SEED OIL/PALM OIL/ AMINOPROPANEDIOL ESTERS ACETATE ETHYLDIMONIUM CHLORIDE

3.8

A gentle conditioning agent that helps soften hair and skin without heavy buildup, but its palm oil source raises sustainability questions.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Antistatic Agent

PEG-10 Coco-Benzonium Chloride

PEG-10 Coco-Benzonium Chloride

3.5

A synthetic conditioning agent that reduces static and softens hair, but may cause irritation for sensitive scalps.

Irritation

moderate

Source

synthetic

beautyhair careconditioning agent
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Antistatic Agent

PEG-2 Cocomonium Chloride

PEG-2 Cocomonium Chloride

3.5

A synthetic conditioning ingredient that reduces static and softens hair, but may cause irritation for sensitive scalps at high concentrations.

Irritation

moderate

Source

synthetic

beautyhaircareconditioning agent
Read ingredient review

Antistatic Agent

PEG-3 Tallow Propylenedimonium Dimethosulfate

PEG-3 TALLOW PROPYLENEDIMONIUM DIMETHOSULFATE

3.5

A conditioning ingredient from animal-derived tallow that softens hair and reduces static, but may be too heavy for fine hair or oily skin.

Irritation

moderate

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Skin conditioning agent

PEG-4 Proline Linolenate

PEG-4 Proline Linolenate

3.8

A gentle, semi-synthetic conditioning ingredient that may support skin barrier function, but research is limited and it's not a star performer on its own.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
Read ingredient review

Antistatic Agent

PEG-5 Cocomonium Methosulfate

PEG-5 COCOMONIUM METHOSULFATE

3.5

A gentle, coconut-derived conditioning ingredient that helps reduce static and soften hair without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyhaircareconditioning agent
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Conditioning agent

PEG-7 Amodimethicone

PEG-7 Amodimethicone

4.0

A gentle silicone that smooths hair and reduces frizz without heavy buildup, but may not suit very fine or low-porosity hair.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
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Emollient

PEG-7 Methyl Ether Dimethicone

PEG-7 METHYL ETHER DIMETHICONE

4.0

A gentle, water-soluble silicone that helps products glide on smoothly without a heavy or greasy feel.

Irritation

low

Source

semi-synthetic

beautyskincareconditioning agent
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Hair Conditioner

PEG-8 Amodimethicone

PEG-8 Amodimethicone

4.0

A gentle silicone that coats hair to reduce tangles and add shine without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
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Skin conditioning agent

PEG-9 Dinicotinate

PEG-9 Dinicotinate

3.5

PEG-9 Dinicotinate is a synthetic derivative of niacin (vitamin B3) that may support skin microcirculation and barrier function, but research is limited and it's less common than niacinamide.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
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Antistatic Agent

PEG/PPG-1/25 Diethylmonium Chloride

PEG/PPG-1/25 Diethylmonium Chloride

3.5

A synthetic conditioning ingredient that helps reduce static and improve the feel of hair and skin, but may not suit those avoiding PEGs.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
Read ingredient review

Hair Conditioning Agent

Pentaclethra Macroloba Seed Amide DMAPA

PENTACLETHRA MACROLOBA SEED AMIDE DMAPA

3.8

A gentle conditioning ingredient that helps soften hair and skin without heavy buildup, though research is limited.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Antistatic agent

Perfluoroalkyl Quat

C4-18 Perfluoroalkylethyl Thiohydroxypropyltrimonium Chloride

3.0

A synthetic fluorinated ingredient that helps repel water and reduce frizz, but its environmental persistence raises concerns.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
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Skin Conditioning Agent

Perfluorocaprylyl Bromide

PERFLUOROCAPRYLYL BROMIDE

3.5

A synthetic fluorinated compound that may help deliver oxygen to the skin, but its cosmetic benefits are not well-established and it is rarely used.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
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Oxygen carrier

Perfluorodecalin

PERFLUORODECALIN

3.8

Perfluorodecalin is a synthetic oxygen carrier that may temporarily improve skin oxygenation and radiance, but its cosmetic benefits are still being studied.

Irritation

low

Source

synthetic

beautyskincareconditioning agent
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Hair Conditioner

PG-Amodimethicone

PG-Amodimethicone

4.0

A gentle silicone that coats hair strands for slip, shine, and manageability, with less buildup than traditional dimethicone.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
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Skin conditioning

Pisces Extract

Pisces Extract

3.0

Pisces Extract is a fish-derived ingredient that may offer moisturizing benefits, but scientific evidence is limited and it may not be suitable for vegans or those with fish allergies.

Irritation

low

Source

natural

beautyskincareconditioning agent
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Film Former

Polyquaternium

Polyquaternium

4.0

Polyquaternium is a synthetic polymer that smooths hair and skin by forming a thin, flexible film, but some types may cause buildup with frequent use.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
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Antistatic Agent

Polyquaternium-10

Polyquaternium-10

4.0

A gentle conditioning polymer that reduces flyaways and improves wet combing without heavy buildup.

Irritation

low

Source

semi-synthetic

beautyskincarehaircareconditioning agent
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Film Former

Polyquaternium-100

Polyquaternium-100

4.0

A gentle, effective detangler and antistatic agent that leaves hair smooth and manageable without buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
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Film Former

Polyquaternium-106

Polyquaternium-106

4.0

Polyquaternium-106 is a gentle synthetic polymer that smooths hair, reduces frizz, and improves manageability without heavy buildup.

Irritation

low

Source

synthetic

beautyhaircareconditioning agent
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Film Former

Polyquaternium-107

Polyquaternium-107

4.0

Polyquaternium-107 is a gentle conditioning polymer that reduces frizz and static without heavy buildup, making it suitable for fine or oily hair types.

Irritation

low

Source

synthetic

beautyskincarehaircareconditioning agent
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