Overview
What it is
Ampoule with 24 ingredients
Cool Features
It is reef safe
Suited For
It has ingredients that are good for anti aging, dry skin, sensitive skin, scar healing and dark spots
Free From
It doesn't contain any harsh alcohols, parabens, silicones or sulfates
Fun facts
Secret Key is from South Korea.
We independently verify ingredients and our claims are backed by peer-reviewed research. Does this product need an update? Let us know.
What's inside
Ingredients List
Galactomyces Ferment Filtrate
HumectantWater
Skin ConditioningGlycereth-26
HumectantRosa Centifolia Flower Water
Skin ConditioningMethyl Gluceth-20
Humectant1,2-Hexanediol
Skin ConditioningGlycerin
HumectantPropanediol
SolventGlyceryl Polyacrylate
Arginine
MaskingAmmonium Acryloyldimethyltaurate/Vp Copolymer
PPG-26-Buteth-26
Skin ConditioningAdenosine
Skin ConditioningSodium Polyacrylate
AbsorbentPEG-40 Hydrogenated Castor Oil
EmulsifyingCarbomer
Emulsion StabilisingDisodium EDTA
Caprylyl Glycol
EmollientEthylhexylglycerin
Skin ConditioningParfum
MaskingCitral
PerfumingGeraniol
PerfumingLimonene
PerfumingLinalool
PerfumingGalactomyces Ferment Filtrate, Water, Glycereth-26, Rosa Centifolia Flower Water, Methyl Gluceth-20, 1,2-Hexanediol, Glycerin, Propanediol, Glyceryl Polyacrylate, Arginine, Ammonium Acryloyldimethyltaurate/Vp Copolymer, PPG-26-Buteth-26, Adenosine, Sodium Polyacrylate, PEG-40 Hydrogenated Castor Oil, Carbomer, Disodium EDTA, Caprylyl Glycol, Ethylhexylglycerin, Parfum, Citral, Geraniol, Limonene, Linalool
Benefits
Concerns
Ingredients Explained
Galactomyces Ferment Filtrate (GFF) is a byproduct of fermenting Galactomyces yeast (the same yeast traditionally used to brew sake, Japan's beloved rice wine).
Sake brewers have long been known for their remarkably youthful hands. This is what actually first sparked scientific interest in GFF's skin benefits.
GFF works by stimulating filaggrin production in the skin. Filaggrin is a protein that binds structural proteins in the outer skin layer together to form a tight barrier that shields against allergens, bacteria, and moisture loss.
It's also a key building block of our natural moisturizing factors (NMF), or the network of compounds that keep skin plump and hydrated.
By boosting filaggrin, GFF helps strengthen both our barrier and our skin's ability to retain moisture.
Beyond hydration, GFF has notable antioxidant properties that help protect against oxidative stress and UV-induced inflammation.
Research also suggests it may help regulate sebum and keratin production. This could be an interesting option for those concerned about oiliness or skin texture.
Fungal acne:
This ingredient doesn't contain fatty acids or oils that could feed Malassezia, and the yeast used to make it (Galactomyces) is a different genera of fungi from Malassezia. The presence of one doesn't stimulate the other.
However, there is a concern raised by some communities that this ingredient could trigger a reaction in people who are broadly sensitive to yeast/fungal-derived ingredients.
Learn more about Galactomyces Ferment FiltrateWater. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!
Learn more about WaterGlycereth-26 is a synthetic ingredient and polyethylene glycol ether of Glycerin. Glycerin is already naturally found in your skin and helps keep your skin moisturized.
It is a humectant and helps add texture to products. It can make your product thicker.
As a humectant, it helps draw moisture from the air to your skin. This helps your skin stay hydrated.
Learn more about Glycereth-26Rosa Centifolia Flower Water is the steam distilled water from the petals of Rosa centifolia, a rose cultivated in France, Bulgaria, and Morocco. It has skin conditioning and soothing properties due to its rich antioxidant content.
Since it's the water-soluble part of distilling rose petals, it's lighter and more dilute than rose extract or essential oil.
Research suggests it can help counteract the enzymes involved in the breakdown of collagen and elastin and have antimicrobial activity against acne-related microorganisms. A comprehensive 2025 review confirmed that Rosa centifolia extracts demonstrate anti-inflammatory, antimicrobial, and antioxidant effects.
Learn more about Rosa Centifolia Flower WaterMethyl Gluceth-20 is a humectant. Humectants help draw moisture from the air to your skin.
It is created by combining polyethylene glycol with glucose.
1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.
It is a:
- Humectant, drawing moisture into the skin
- Emollient, helping to soften skin
- Solvent, dispersing and stabilizing formulas
- Preservative booster, enhancing the antimicrobial activity of other preservatives
Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
Topically, glycerin does several things at once:
Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.
Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.
This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.
Just know very high concentrations (>40%) can feel tacky in low humidity.
Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Learn more about GlycerinPropanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
It’s often used to:
Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
Learn more about PropanediolWe don't have a description for Glyceryl Polyacrylate yet.
Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.
It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.
Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.
A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.
Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.
One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.
Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.
Learn more about ArginineAmmonium Acryloyldimethyltaurate/Vp Copolymer is a synthetically created polymer. It's used as a film-forming agent and used to thicken the consistency of products.
Think of it as a supportive ingredient that helps your gel-creams feel silky, "cloud cream-like", and spread evenly without being greasy.
The Cosmetic Ingredient Review (CIR) Expert Panel evaluated it (along with 22 other acryloyldimethyltaurate polymers) and concluded it's:
Due to its large molecular size, it sits on the surface of skin rather than penetrating it.
Learn more about Ammonium Acryloyldimethyltaurate/Vp CopolymerWe don't have a description for PPG-26-Buteth-26 yet.
Adenosine is in every living organism. It is one of four components in nucleic acids that helps store our DNA.
Adenosine has many benefits when used. These benefits include hydrating the skin, smoothing skin, and reducing wrinkles. Once applied, adenosine increases collagen production. It also helps with improving firmness and tissue repair.
Studies have found adenosine may also help with wound healing.
In skincare products, Adenosine is usually derived from yeast.
Learn more about AdenosineSodium Polyacrylate is the sodium salt of polyacrylic acid. It is used as an absorber, emollient, and stabilizer.
This ingredient is a super-absorbent polymer - meaning it can absorb 100 to 1000 times its mass in water. As an emollient, Sodium Polyacrylate helps soften and soothe skin. Emollients work by creating a barrier to trap moisture in. This helps keep your skin hydrated.
PEG-40 Hydrogenated Castor Oil is an emulsifier derived from castor oil.
As an emulsifying agent, it helps other ingredients like fragrances and fat-soluble vitamins dissolve cohesively.
Due to its large molecule size, it doesn't penetrate beyond the skin's surface.
This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.
A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.
Learn more about PEG-40 Hydrogenated Castor OilCarbomer is a high-molecular weight polymer of acrylic acid. It is used to form gels and thicken formulas.
Due to its large molecular size, carbomer has minimal skin penetration and is considered an inert ingredient.
A high amount of carbomer can cause pilling or balling up of products. Don't worry, most products contain 1% or less of carbomer.
Learn more about CarbomerDisodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.
This ingredient mainly works behind the scenes and helps with:
On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.
One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).
Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.
You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.
Learn more about Disodium EDTACaprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
Learn more about Caprylyl GlycolEthylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.
Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
Learn more about EthylhexylglycerinParfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumCitral is the molecule responsible for the fresh lemon scent in lemon, lime, and lemongrass. It is a fragrance ingredient that can be created from plant essential oils or synthetically.
Though Citral has documented antimicrobial activity against acne bacteria (which is where the marketing claims about it being good for acne-prone skin originate), real formulas use it at fragrance-level concentrations under 1% so there's likely no skin benefit.
You should know this ingredient is a known EU fragrance allergen.
Animal studies classifies this ingredient as a weak-to-moderate skin sensitizer and clinical patch testing on eczema patients confirmed it to be both a contact allergen and irritant.
The term 'citral' is a collective term for two geometric isomers: geranial/Citral A and neral/Citral B.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about CitralGeraniol is used to add fragrance/parfum to a product. It is the main component of citronellol. It is a monoterpenoid and an alcohol.
Monoterpenes are naturally found in many parts of different plants.
Geraniol can be found in many essential oils including Rose Oil and Citronella Oil. The scent of Geraniol is often described as "rose-like". Many foods also contain Geraniol for fruit flavoring.
Geraniol can irritate the skin when exposed to air. However, irritation depends on the ability of geraniol to penetrate into the skin. In general, geraniol is not able to penetrate skin easily.
Geraniol is colorless and has low water-solubility. However, it is soluble in common organic solvents.
Like citronellol, it is a natural insect repellent.
2,6-Octadien-1-ol, 3,7-dimethyl-, (2E)-
Learn more about GeraniolLimonene is a fragrance that adds scent and taste to a formulation.
It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".
Limonene acts as an antioxidant, meaning it helps neutralize free radicals.
When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about LimoneneLinalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
Like Limonene, this ingredient oxidizes when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.
This ingredient has a scent that is floral, spicy tropical, and citrus-like.
Learn more about LinaloolReviews
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Where it's from
Secret Key is a Korean brand
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We're dedicated to providing you with the most up-to-date and science-backed ingredient info out there.
The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Published October 6, 2022 • Added by WinglessTori