Hair Serum
Hair Serum
American United States
Australian Australia

What's inside

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Show highlights for:

Water

Skin Conditioning

Pentylene Glycol

Skin Conditioning
Good for Barrier Repair Icon

Dimethicone

Emollient
1 / 0 Silicon IconGood for Scar Healing Icon

Salvia Hispanica Seed Extract

Emollient

PPG-3 Benzyl Ether Myristate

Emollient

Cetyl Alcohol

Emollient
2 / 2 Fatty Alcohol IconCoconut Derived IconNot safe for Fungal Acne Icon

Dimethiconol Meadowfoamate

Emollient

Brassica Alcohol

Emollient
Fatty Alcohol IconNot safe for Fungal Acne Icon

Parfum

Masking
Synthetic Fragrance IconFragrance IconMay worsen Eczema IconMay worsen Rosacea Icon

Polyquaternium-37

Guar Hydroxypropyltrimonium Chloride

Skin Conditioning

Behentrimonium Chloride

Preservative
Preservative Icon

Caprylyl Methicone

Skin Conditioning
Silicon Icon

Benzyl Alcohol

Perfuming
Alcohol IconFragrance IconPreservative IconMay worsen Eczema IconMay cause irritation IconEU Allergen Icon

Brassicyl Valinate Esylate

Emollient

Glycerin

Humectant
0 / 0 Helps hydrate Dry Skin IconGood for Scar Healing IconGood for Barrier Repair Icon

Panthenol

Skin Conditioning
0 / 0 Helps hydrate Dry Skin IconHelps reduce irritation IconHelps reduce Skin Redness IconGood for Scar Healing IconGood for Barrier Repair Icon

Chlorphenesin

Antimicrobial
Preservative Icon

Sodium Benzoate

Masking
Preservative Icon

Calcium Gluconate

Humectant

Trehalose

Humectant
Helps with Anti-Aging IconHelps hydrate Dry Skin IconGood for Barrier Repair Icon

Xylitol

Humectant
Helps hydrate Dry Skin IconGood for Barrier Repair Icon

Butylene Glycol

Humectant
1 / 0 Helps hydrate Dry Skin IconGood for Barrier Repair Icon

Hydrolyzed Rice Protein

Skin Conditioning

Citric Acid

Buffering
AHA IconHelps brighten skin IconMay worsen Rosacea Icon

Polyquaternium-73

Caprylyl/Capryl Glucoside

Cleansing

Isopropyl Alcohol

Solvent
0 / 0 Alcohol IconCan worsen Dry Skin IconMay worsen Eczema IconMay cause irritation IconMay worsen Rosacea Icon

Oryza Sativa Bran Extract

Skin Conditioning
Helps hydrate Dry Skin Icon

Panthenyl Hydroxypropyl Steardimonium Chloride

Quaternium-95

UV Absorber

Tetrasodium Glutamate Diacetate

Ethyl Linoleate

Emollient
Fragrance IconNot safe for Fungal Acne Icon

Ceramide NP

Skin Conditioning
Ceramide IconHelps with Anti-Aging IconHelps hydrate Dry Skin IconHelps reduce irritation IconHelps reduce Skin Redness IconGood for Barrier Repair Icon

Ethyl Oleate

Emollient
Fragrance IconNot safe for Fungal Acne Icon

Sorbitan Oleate

Emulsifying
3 / 0 Bad for Acne Prone Skin IconNot safe for Fungal Acne Icon

Leuconostoc/Radish Root Ferment Filtrate

Antimicrobial
Not safe for Fungal Acne Icon

Sodium PCA

Humectant
0 / 0 Helps hydrate Dry Skin IconHelps reduce irritation IconGood for Barrier Repair Icon

Cinnamidopropyltrimonium Chloride

Arctium Lappa Root Extract

Skin Conditioning
Helps reduce irritation Icon

Hedera Helix Extract

Antimicrobial

Sodium Lactate

Buffering
Helps hydrate Dry Skin Icon

Trigonella Foenum-Graecum Seed Extract

Perfuming
Fragrance Icon

Propanediol

Solvent
Helps hydrate Dry Skin IconGood for Barrier Repair Icon

Sodium Phosphate

Buffering

Lactobacillus/Arundinaria Gigantea Leaf Ferment Filtrate

Skin Conditioning

Arginine

Masking
Helps hydrate Dry Skin IconGood for Scar Healing Icon

Helianthus Annuus Extract

Emollient
Helps hydrate Dry Skin Icon

Aspartic Acid

Masking
Helps hydrate Dry Skin Icon

PCA

Humectant
Helps hydrate Dry Skin Icon

Litchi Chinensis Fruit Extract

Skin Conditioning

Citrullus Lanatus Seed Oil

Emollient
Oil IconHelps reduce irritation IconNot safe for Fungal Acne Icon

Phenoxyethanol

Preservative
Preservative Icon

Caprylic Acid

Cleansing
1 / 3

Galactoarabinan

Helps reduce Skin Redness Icon

Tocopherol

Antioxidant
0-3 / 0-3 Vitamin E IconAntioxidant IconHelps with Anti-Aging IconHelps hydrate Dry Skin IconHelps brighten skin IconHelps reduce Skin Redness IconGood for Dark Spots IconGood for Barrier Repair Icon

Rosmarinus Officinalis Leaf Extract

Antimicrobial

Leontopodium Alpinum Extract

Skin Conditioning

Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol

Skin Conditioning

Glycine

Buffering
Helps hydrate Dry Skin Icon

Alanine

Masking
Helps hydrate Dry Skin Icon

Potassium Sorbate

Preservative
Preservative Icon

Sodium Acetylated Hyaluronate

Humectant
Hyaluronic Acid IconHelps with Anti-Aging Icon

Camellia Sinensis Leaf Extract

Antimicrobial
Antioxidant IconHelps with Anti-Aging IconHelps hydrate Dry Skin IconHelps brighten skin IconHelps reduce irritation IconGood for Oily Skin IconGood for Minimizing Pores IconHelps reduce Skin Redness Icon

Sodium Hyaluronate

Humectant
0 / 0 Hyaluronic Acid IconHelps with Anti-Aging IconHelps hydrate Dry Skin IconHelps reduce Skin Redness IconGood for Barrier Repair Icon

Serine

Masking
Helps hydrate Dry Skin Icon

Valine

Masking

Ethylhexylglycerin

Skin Conditioning

Gossypium Herbaceum Seed Extract

Skin Conditioning

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Antioxidant
Antioxidant Icon

Sodium Hyaluronate Crosspolymer

Humectant
Hyaluronic Acid IconHelps hydrate Dry Skin IconGood for Scar Healing Icon

Sodium Hydroxide

Buffering

Isoleucine

Skin Conditioning

Proline

Skin Conditioning
Helps hydrate Dry Skin Icon

Threonine

Helps hydrate Dry Skin Icon

Nigella Sativa Seed Extract

Perfuming
Fragrance Icon

Hydrolyzed Sodium Hyaluronate

Skin Conditioning
Helps hydrate Dry Skin IconHelps reduce irritation IconGood for Scar Healing Icon

Histidine

Humectant
Helps with Anti-Aging IconHelps hydrate Dry Skin Icon

Phenylalanine

Masking
Helps hydrate Dry Skin Icon

Caprylyl Glycol

Emollient
Fatty Alcohol Icon

Disodium EDTA

Potassium Hydroxide

Buffering

Limonene

Perfuming
Fragrance IconMay worsen Eczema IconMay cause irritation IconMay worsen Rosacea IconEU Allergen Icon

Hexyl Cinnamal

Perfuming
Synthetic Fragrance IconFragrance IconMay cause irritation IconEU Allergen Icon

Citral

Perfuming
Fragrance IconMay worsen Eczema IconMay cause irritation IconMay worsen Rosacea IconEU Allergen Icon

Linalool

Perfuming
Fragrance IconMay worsen Eczema IconMay cause irritation IconMay worsen Rosacea IconEU Allergen Icon

Water, Pentylene Glycol, Dimethicone, Salvia Hispanica Seed Extract, PPG-3 Benzyl Ether Myristate, Cetyl Alcohol, Dimethiconol Meadowfoamate, Brassica Alcohol, Parfum, Polyquaternium-37, Guar Hydroxypropyltrimonium Chloride, Behentrimonium Chloride, Caprylyl Methicone, Benzyl Alcohol, Brassicyl Valinate Esylate, Glycerin, Panthenol, Chlorphenesin, Sodium Benzoate, Calcium Gluconate, Trehalose, Xylitol, Butylene Glycol, Hydrolyzed Rice Protein, Citric Acid, Polyquaternium-73, Caprylyl/Capryl Glucoside, Isopropyl Alcohol, Oryza Sativa Bran Extract, Panthenyl Hydroxypropyl Steardimonium Chloride, Quaternium-95, Tetrasodium Glutamate Diacetate, Ethyl Linoleate, Ceramide NP, Ethyl Oleate, Sorbitan Oleate, Leuconostoc/Radish Root Ferment Filtrate, Sodium PCA, Cinnamidopropyltrimonium Chloride, Arctium Lappa Root Extract, Hedera Helix Extract, Sodium Lactate, Trigonella Foenum-Graecum Seed Extract, Propanediol, Sodium Phosphate, Lactobacillus/Arundinaria Gigantea Leaf Ferment Filtrate, Arginine, Helianthus Annuus Extract, Aspartic Acid, PCA, Litchi Chinensis Fruit Extract, Citrullus Lanatus Seed Oil, Phenoxyethanol, Caprylic Acid, Galactoarabinan, Tocopherol, Rosmarinus Officinalis Leaf Extract, Leontopodium Alpinum Extract, Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol, Glycine, Alanine, Potassium Sorbate, Sodium Acetylated Hyaluronate, Camellia Sinensis Leaf Extract, Sodium Hyaluronate, Serine, Valine, Ethylhexylglycerin, Gossypium Herbaceum Seed Extract, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Hyaluronate Crosspolymer, Sodium Hydroxide, Isoleucine, Proline, Threonine, Nigella Sativa Seed Extract, Hydrolyzed Sodium Hyaluronate, Histidine, Phenylalanine, Caprylyl Glycol, Disodium EDTA, Potassium Hydroxide, Limonene, Hexyl Cinnamal, Citral, Linalool

Water

Skin Conditioning

Cetearyl Alcohol

Emollient
2 / 1 Fatty Alcohol IconCoconut Derived IconBad for Acne Prone Skin IconMay worsen Oily Skin IconNot safe for Fungal Acne Icon

Cetyl Alcohol

Emollient
2 / 2 Fatty Alcohol IconCoconut Derived IconNot safe for Fungal Acne Icon

Cetrimonium Chloride

Antimicrobial
Preservative Icon

Phenoxyethanol

Preservative
Preservative Icon

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Masking, Skin Conditioning

Alanine is an amino acid and is already found in the human body. Our skin uses alanine to build collagen, elastin, and keratin.

Masking, Skin Conditioning

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 Arginine
Masking, Skin Conditioning

Aspartic Acid is an amino acid that our bodies produce naturally. It is an antioxidant.

Our body uses Aspartic Acid to help build collagen and elastin. It also plays a role in hydrating skin.

This ingredient is a preservative and often used for it's anti-static properties. You'll most likely see this ingredient in hair conditioners.

It does not cause irritation or sensitization in leave-on products at 1-5%.

Perfuming, Preservative, Solvent

Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.

This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.

As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.

The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.

This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.

It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.

Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.

At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.

Learn more about Benzyl Alcohol
Humectant, Masking, Skin Conditioning

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Learn more about Butylene Glycol
Cleansing, Emulsifying, Masking

This ingredient is also known as octanoic acid. It is a fatty acid that is naturally found in (and sourced from) coconut oil and palm kernel oil.

In cosmetics, it plays several roles:

The antimicrobial activity has been documented: Caprylic Acid is able to disrupt microbial cell membranes and is confirmed to be effective against some bacteria and yeasts.

Cosmetic use levels are often under 5% because very high concentrations (70-99%) can be corrosive as shown in patch-testing.

On the fungal acne side, Caprylic Acid sits outside the C11-24 range that the Malassezia yeast can metabolize. It is also one of the more studied fatty acids for anti-Malassezia activity; a study from 2020 showed that just 0.2 caprylic acid was enough to disrupt Malassezia furfur under a Transmission Electron Microscope.

The comedogenic rating of 1 and irritancy rating of 3 comes from the 1989 Rabbit Ear Study. Since rabbit ear models produce a lot of false positives, anything scoring 0-1 means it is unlikely to cause comedones in humans.

The 3 for irritancy reflects that capylic acid is a weak organic acid that is corrosive in undiluted form.

Just so you know, both of these numbers came from being tested at 100% on hypersensitive rabbit skin. This is going to look very different at the <5% use levels in your cosmetics.

Plus, comedogenicity is more about the finished formula rather than individual ingredients. Be sure to patch test if you're unsure!

Learn more about Caprylic Acid
Cleansing, Foaming, Surfactant

This ingredient is a mild surfactant made by sticking glucose onto a blend of fatty acids.

It does two jobs because it has a sugar head that loves water and a fatty tail that loves oil:

Typical use levels range from 10-20% in cleansers and 15-30% in shower products.

Once on your skin, your skin's glucoside hydrolases breaks it down into glucose and the parent fatty alcohols.

This ingredient is considered fungal acne safe because its fatty alcohol portion sits outside the Malassezia yeast's metabolization range.

Learn more about Caprylyl/Capryl Glucoside
Emollient, Emulsifying, Emulsion Stabilising

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Its main roles are:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

Learn more about Cetyl Alcohol
Perfuming

Citral 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 Citral
Buffering, Masking

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Read more about some other popular AHA's here:

Learn more about Citric Acid
Emollient, Perfuming

Ethyl Linoleate is a fragrance and isn't fungal acne safe.

Emollient, Perfuming

Ethyl Oleate is a fragrance and isn't fungal acne safe.

Humectant, Skin Conditioning, Skin Protecting

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 Glycerin
Buffering, Skin Conditioning

Glycine is the smallest amino acid and a key building block of collagen. It's part if 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.

A study from 2022 found that an amino acid complex featuring taurine, arginine, and glycine significantly reduced skin irritation, improved redness, and accelerated the skin repair process.

This ingredient is derived from guar gum. It is a skin conditioning agent that creates a thin, breathable film to reduce water loss during cleansing.

This leaves the skin feeling soft rather than stripped and also contributes to a creamier lather.

Due to the large molecule size, this ingredient is unlikely to penetrate skin.

Learn more about Guar Hydroxypropyltrimonium Chloride
Humectant, Skin Conditioning

Histidine is a semi-essential amino acid used by our bodies to create protein. It has humectant and skin conditioning properties.

Our bodies use histidine to create filaggrin - filaggrin is a structural protein that the skin uses in maintaining skin barrier.

One study found histidine and carnosine to be a dynamic duo for your skin:

Oral histidine has also been found to help with filaggrin-deficit skin disorders such as atopic dermatitis.

Why is it considered a semi-essential amino acid? This is because adults are able to create it but children must get it from their diet.

Learn more about Histidine
Skin Conditioning

Isoleucine is an amino acid that helps reinforce our skin barrier. This amino acid plays a role in creating protein for the body.

Fun fact: Isoleucine is found in meat, fish, dairy, legumes, and nuts.

Perfuming, Solvent

Limonene 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 Limonene
Perfuming

Linalool 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 Linalool
Skin Conditioning

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

Learn more about Panthenol
Masking, Perfuming

Parfum 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 Parfum
PCA
Humectant, Moisturising

PCA is derived from amino acids and is naturally found in our skin's barrier.

As a humectant, PCA helps draw and hold moisture to the skin. Studies show it is effective at helping the skin stay hydrated long-term.

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate (long name, huh?) is a synthetic antioxidant.

It is used to help stabilize other antioxidants or prevent the color from changing in a product.

As an antioxidant, it helps fight free-radical molecules. Free-radical molecules are capable of damaging our cells and other genetic material. Thus, antioxidants may reduce the signs of aging.

This ingredient is oil-soluble.

Learn more about Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate
Preservative

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.

Masking, Skin Conditioning

Phenylalanine is an amino acid. It is a skin soothing and hydrating ingredient. Amino acids play a crucial role in wound healing and skin hydration.

This ingredient is also used to help even out skin tone due to its ability to disrupt the melanin production process.

Two structures of phenylalanine exist: L-phenylalanine and D-phenylalanine. L-phenylalanine is essential, this means our bodies cannot produce it naturally and we must get it from foods. Our bodies convert D-phenylalanine to neurotransmitters, and D-phenylalanine is found in our bodies naturally.

Some foods that contain L-phenylalanine include eggs, soybeans, beef, milk.

Learn more about Phenylalanine
Preservative

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Learn more about Potassium Sorbate
Skin Conditioning

Proline is a non-essential amino acid, meaning your body can make it on its own. In skincare, it is a skin conditioning ingredient that keeps skin soft and hydrated.

It makes up about 23% of the collagen molecule (collagen is the protein responsible for keeping your skin firm) and is involved in your skin's natural hyaluronic acid production. When applied topically, proline can penetrate the skin fairly well due to its small molecular size.

Reviews of this ingredient have found it to be neither a dermal irritant nor a sensitizer.

Fun fact: Proline can be found in protein-rich foods like meat, fish, eggs, and dairy.

Learn more about Proline
Antimicrobial, Masking, Skin Conditioning

This is a botanical extract from the rosemary plant (the same one you cook with). In skincare, it mostly works as a skin conditioning agent.

Its activity comes from a handful of polyphenols, carnosic acid, carnosol, and rosmarinic acid. Almost 90% of the antioxidant activity of this ingredient can be attributed to canosol and carnosic acid.

These compounds protect your skin two ways:

1) They fight off free radicals, or the unstable molecules from things like sun and pollution that age and damage skin.
2) They help calm inflammation by switching off the chemical signals that tell skin to get red and irritated.

Lab studies also suggest that rosmarinic acid may help protect collagen and slow sugar-related damage to it.

The Cosmetic Ingredient Review has concluded rosemary-derived ingredients to be safe when formulated to be non-sensitizing.

Rosemary can occasionally cause allergic contact dermatitis (due to carnosol), so be sure to patch test if you have reactive or fragrance-sensitive skin.

Learn more about Rosmarinus Officinalis Leaf Extract
Masking, Skin Conditioning

Serine is a non-essential amino acid (your body makes it on its own!). It is a major player in 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.

Serine is one of your NMF's most abundant components that works as a skin-identical humectant. Its hydroxyl group grabs onto water molecules to boost hydration without any heaviness or occlusion.

Research on a hydrogel with serine confirmed this serine got delivered to your stratum corneum and demonstrated enhanced skin moisturization.

Interestingly serine also helps your skin produce filaggrin, a protein that keeps your skin barrier strong and used to create collagen.

Learn more about Serine
Masking, Preservative

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Learn more about Sodium Benzoate
Humectant, Skin Conditioning

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Learn more about Sodium Hyaluronate
Buffering, Humectant

Sodium Lactate is the sodium salt of lactic acid, an AHA. It is a humectant and sometimes used to adjust the pH of a product.

This ingredient is part of our skin's NMF, or natural moisturizing factor. Our NMF is essential for the hydration of our top skin layers and plasticity of skin. NMF also influences our skin's natural acid mantle and pH, which protects our skin from harmful bacteria.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Learn more about Sodium Lactate
Humectant, Skin Conditioning

Sodium PCA is the sodium salt of pyroglutamic acid. It is naturally occurring in our skin's natural moisturizing factors where it works to maintain hydration.

The PCA stands for pyrrolidone carboxylic acid, a natural amino acid derivative.

This ingredient has skin conditioning, anti-inflammatory, and humectant properties. Humectants help hydrate your skin by drawing moisture from the air. This helps keep your skin moisturized.

Learn more about Sodium PCA

Threonine is an amino-acid. It helps hydrate the skin and has antioxidant benefits.

Our skin uses threonine for creating collagen and elastin. Humans are not able to create threonine and must get it through eating foods such as fish, lentils, poultry, sesame seeds, and more.

Antioxidant, Masking, Skin Conditioning

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

Learn more about Tocopherol
Masking, Skin Conditioning

Valine is an essential amino acid. It is used by our bodies for tissue repair and muscle growth.

An essential amino acid is one in which our bodies cannot naturally produce so we must get them through diet. Foods such as eggs, dairy, red meat, and fish contain valine.

This ingredient can either be derived from an animal product or be synthetically created.

Learn more about Valine
Skin Conditioning, Solvent

Water. 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 Water
Humectant, Skin Conditioning

Xylitol is a humectant and prebiotic. It can help with dry skin.

In studies, xylitol has been shown to improve dry skin. It decreased transepidermal water loss, or when water passes through the skin and evaporates. Xylitol also showed to help improve the biomechanical properties of the skin barrier.

The prebiotic property of xylitol may also help reinforce our skin's natural microbiome. Having a healthy microbiome prevents infection by bad bacteria and helps with hydration.

As a humectant, Xylitol helps draw moisture from both the air and from deeper skin layers. This helps keep skin hydrated.

Xylitol is a sugar alcohol and commonly used as a sugar substitute. It is naturally occurring in plants such as strawberries and pumpkin.

Learn more about Xylitol

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