Encyclopedia
Every molecule that touches your hair
From proven medicines to kitchen-cupboard oils, with the studies behind each one.
26 entries
A
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other
Alcohol denat.
Ordinary ethanol made undrinkable, a fast-drying solvent in hair sprays and gels that is not the same as the fatty alcohols in conditioners.
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botanical
Aloe vera
Aloe gel is a soothing, water-binding scalp and hair conditioner, with no solid human trial showing it grows hair.
C
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anti dandruff
Ciclopirox
An antifungal shampoo ingredient with randomized-trial support for scalp seborrheic dermatitis and a particular edge on itch, with no good evidence that it grows hair.
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anti dandruff
Climbazole
A cosmetic azole antifungal used mostly as a booster next to zinc pyrithione or piroctone olamine, with thin evidence on its own.
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anti dandruff
Coal tar
One of the oldest dandruff and psoriasis treatments; it works, but it contains carcinogens, smells, stains and is no longer anyone's first choice.
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surfactant
Cocamide MEA and cocamide DEA
Foam boosters and thickeners in shampoo; the DEA type raises nitrosamine and allergy questions, which is why many brands moved to MEA or other thickeners.
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surfactant
Cocamidopropyl betaine
The most common helper surfactant in shampoo, which makes sulfate cleansers gentler, thicker and foamier, and a rare cause of scalp allergy that usually comes from manufacturing impurities.
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surfactant
Coco-glucoside
A coconut-derived mild cleanser that is a staple of sulfate-free shampoos, with the same contact-allergy caveat as decyl glucoside.
D
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surfactant
Decyl glucoside
A plant-derived mild cleanser marketed as ultra-gentle, but its best-documented concern is a rising rate of contact allergy.
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surfactant
Disodium laureth sulfosuccinate
A mild anionic cleanser often used as a secondary or co-primary surfactant that helps blends stay gentle while still cleaning.
G
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protein or peptide
GHK-Cu (copper tripeptide-1)
GHK-Cu is a copper-binding peptide with a long skin-repair record but no published controlled trial for hair growth.
K
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anti dandruff
Ketoconazole
An antifungal shampoo ingredient that is among the best-proven treatments for dandruff and, with much weaker evidence, a possible add-on for pattern hair loss.
L
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surfactant
Lauryl glucoside
A 12-carbon alkyl glucoside that foams a little better than decyl glucoside and carries the same class contact-allergy profile.
P
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botanical
Peppermint oil
In a 2014 mouse study 3% peppermint oil grew more hair than 3% minoxidil, but no human trial of peppermint oil for hair has been found.
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anti dandruff
Piroctone olamine
A gentle anti-dandruff ingredient common in European shampoos, with trial results roughly equal to zinc pyrithione but mostly from manufacturers.
S
-
anti dandruff
Salicylic acid
A scale-loosening ingredient that helps thick flakes and scalp psoriasis plaques and works best paired with an antifungal.
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anti dandruff
Selenium sulfide
An old, inexpensive anti-dandruff active that new trials suggest works about as well as ketoconazole and has been tested across all curl types.
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surfactant
Sodium cocoamphoacetate
A mild two-charge helper surfactant used in baby, sulfate-free and sensitive-scalp shampoos to soften harsher cleansers.
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surfactant
Sodium cocoyl glutamate
An amino-acid-based cleanser that was among the best-tolerated surfactants in a 105-patient patch-test study, with no scalp or hair trials yet.
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surfactant
Sodium cocoyl glycinate
A glycine-based mild cleanser with one industry body-wash study showing mildness and no scalp or hair studies.
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surfactant
Sodium cocoyl isethionate
A mild anionic cleanser, the basis of many syndet bars, with good lab evidence of being gentle on the skin barrier and growing use in sulfate-free shampoos and shampoo bars.
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surfactant
Sodium lauroamphoacetate
The lauric-chain version of the amphoacetate family, used as a mild helper surfactant in sulfate-free shampoos.
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surfactant
Sodium lauroyl methyl isethionate
A more soluble cousin of sodium cocoyl isethionate used as a mild cleanser in modern sulfate-free shampoos, with no independent studies of its own.
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surfactant
Sodium lauryl sulfate
A cheap, strong cleanser and foamer that removes oil very well but is the most irritating common shampoo surfactant, so dermatologists use it as their standard test irritant.
T
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botanical
Tea tree oil
A popular natural dandruff remedy with modest evidence, whose oxidised oil is a well-documented contact allergen.
Z
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anti dandruff
Zinc pyrithione
The most widely used anti-dandruff shampoo ingredient, proven in large trials to cut flaking, though most of those trials were run by the companies that sell it.