Peptide Skincare & BeautySkin science and ingredient guides

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MEDI-PEEL Gold Age Tox H8 Cream Versus Olehenriksen Strength Trainer Peptide Boost Moisturizer

MEDI-PEEL Gold Age Tox H8 Cream Versus Olehenriksen Strength Trainer Peptide Boost Moisturizer This anti-aging moisturizer is formulated around Niacinamide and Adenosine to soften the look of wrinkles and strengthen the skin barrier. This barrier-repair moistu

MEDI-PEEL Gold Age Tox H8 Cream Versus Olehenriksen Strength Trainer Peptide Boost Moisturizer

This anti-aging moisturizer is formulated around Niacinamide and Adenosine to soften the look of wrinkles and strengthen the skin barrier.

This barrier-repair moisturizer is formulated around Niacinamide and Acetyl Hexapeptide-8 to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Caprylic/Capric Triglyceride

Dipropylene Glycol

Niacinamide

1,2-Hexanediol

Butyrospermum Parkii Butter

Camellia Sinensis Leaf Extract

Carbomer

Dimethicone

Panthenol

Polyglyceryl-2 Stearate

Arachidyl Alcohol

Butylene Glycol

Propanediol

Glyceryl Stearate

Squalane

Glyceryl Glucoside

Stearyl Alcohol

Stearic Acid

Palmitic Acid

C12-16 Alcohols

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Hydrogenated Lecithin

Adenosine

Caprylyl Glycol

Tremella Fuciformis Extract

Tremella Fuciformis Sporocarp Extract

Xanthan Gum

Ethylhexylglycerin

Tocopheryl Acetate

Illicium Verum Fruit Extract

Sodium Hyaluronate

Leuconostoc/Radish Root Ferment Filtrate

Collagen

Proline

Hydroxyproline

Vegetable Amino Acids

Natto Gum

Silk Extract

Palmitoyl Pentapeptide-4

Copper Tripeptide-1

Palmitoyl Tripeptide-1

Acetyl Hexapeptide-8

Oligopeptide-1

Palmitoyl Tripeptide-5

Dipeptide Diaminobutyroyl Benzylamide Diacetate

Scutellaria Baicalensis Root Extract

Cetearyl Alcohol

Arachidyl Glucoside

Benzyl Glycol

Behenyl Alcohol

Ceramide NP

Ceramide Ns

Phytosphingosine

Cholesterol

Hydrolyzed Elastin

Sericin

Ceramide As

Ceramide AP

Gold

Lysine

Glycine

Alanine

Glutamic Acid

Serine

Leucine

Tryptophan

Aspartic Acid

Glutamine

Valine

Threonine

Isoleucine

Phenylalanine

Histidine

Methionine

Cystine

Tyrosine

Asparagine

Ceramide EOP

Polyglyceryl-10 Laurate

CI 19140

CI 16255

Tromethamine

Parfum

Limonene

Alpha-Isomethyl Ionone

Water, Glycerin, Caprylic/Capric Triglyceride, Dipropylene Glycol, Niacinamide, 1,2-Hexanediol, Butyrospermum Parkii Butter, Camellia Sinensis Leaf Extract, Carbomer, Dimethicone, Panthenol, Polyglyceryl-2 Stearate, Arachidyl Alcohol, Butylene Glycol, Propanediol, Glyceryl Stearate, Squalane, Glyceryl Glucoside, Stearyl Alcohol, Stearic Acid, Palmitic Acid, C12-16 Alcohols, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Hydrogenated Lecithin, Adenosine, Caprylyl Glycol, Tremella Fuciformis Extract, Tremella Fuciformis Sporocarp Extract, Xanthan Gum, Ethylhexylglycerin, Tocopheryl Acetate, Illicium Verum Fruit Extract, Sodium Hyaluronate, Leuconostoc/Radish Root Ferment Filtrate, Collagen, Proline, Hydroxyproline, Vegetable Amino Acids, Natto Gum, Silk Extract, Palmitoyl Pentapeptide-4, Copper Tripeptide-1, Palmitoyl Tripeptide-1, Acetyl Hexapeptide-8, Oligopeptide-1, Palmitoyl Tripeptide-5, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Scutellaria Baicalensis Root Extract, Cetearyl Alcohol, Arachidyl Glucoside, Benzyl Glycol, Behenyl Alcohol, Ceramide NP, Ceramide Ns, Phytosphingosine, Cholesterol, Hydrolyzed Elastin, Sericin, Ceramide As, Ceramide AP, Gold, Lysine, Glycine, Alanine, Glutamic Acid, Serine, Leucine, Tryptophan, Aspartic Acid, Glutamine, Valine, Threonine, Isoleucine, Phenylalanine, Histidine, Methionine, Cystine, Tyrosine, Asparagine, Ceramide EOP, Polyglyceryl-10 Laurate, CI 19140, CI 16255, Tromethamine, Parfum, Limonene, Alpha-Isomethyl Ionone

Dicaprylyl Carbonate

Methylpropanediol

Mangifera Indica Seed Butter

Acetyl Hexapeptide-1

Acetyl Octapeptide-3

Acetyl Tetrapeptide-2

Acetyl Dipeptide-1 Cetyl Ester

Palmitoyl Tetrapeptide-7

Carnosine

Lysine Hcl

Arginine

Hyaluronic Acid

Linoleic Acid

Linolenic Acid

Sodium PCA

Sodium Lactate

Tocopherol

Betaine

PCA

Cyanocobalamin

Xylitol

Anhydroxylitol

Xylitylglucoside

Sorbitan Olivate

Hydroxyethylcellulose

Cetearyl Olivate

Sorbitan Laurate

Polysorbate 60

Hydroxyacetophenone

Glycine Soja Oil

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Polysorbate 20

Ammonium Acryloyldimethyltaurate/Beheneth-25 Methacrylate Crosspolymer

Sodium Phytate

Sodium Lauroyl Lactylate

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Citric Acid

Phenoxyethanol

Citral

Linalool

Water, Propanediol, Dicaprylyl Carbonate, Glycerin, Methylpropanediol, Cetearyl Alcohol, Stearyl Alcohol, Mangifera Indica Seed Butter, Niacinamide, Acetyl Hexapeptide-1, Acetyl Hexapeptide-8, Acetyl Octapeptide-3, Acetyl Tetrapeptide-2, Acetyl Dipeptide-1 Cetyl Ester, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Carnosine, Ceramide NP, Ceramide AP, Ceramide EOP, Collagen, Serine, Alanine, Glycine, Glutamic Acid, Lysine Hcl, Threonine, Arginine, Proline, Hyaluronic Acid, Sodium Hyaluronate, Linoleic Acid, Linolenic Acid, Sodium PCA, Sodium Lactate, Panthenol, Tocopherol, Tocopheryl Acetate, Betaine, PCA, Cyanocobalamin, Xylitol, Anhydroxylitol, Xylitylglucoside, Sorbitan Olivate, Carbomer, Hydroxyethylcellulose, Xanthan Gum, Cetearyl Olivate, Sorbitan Laurate, Phytosphingosine, Cholesterol, Polysorbate 60, Butylene Glycol, Hydroxyacetophenone, Glycine Soja Oil, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Polysorbate 20, Ammonium Acryloyldimethyltaurate/Beheneth-25 Methacrylate Crosspolymer, Dimethicone, Sodium Phytate, Sodium Lauroyl Lactylate, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Leuconostoc/Radish Root Ferment Filtrate, Citric Acid, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol, Parfum, Citral, Limonene, Linalool

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Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Acetyl Hexapeptide-8 (also known as Argireline) is a synthetic hexapeptide that is often called a "topical Botox alternative".

It works by mimicking how Botox relaxes muscles; it interferes with the signaling process that tells your facial muscles to contract. This can help soften expression lines like forehead wrinkles or crow's feet over time.

The comparison to Botox does have limits because the molecule is water-loving and relatively large.

Acetyl Hexapeptide-8 has a hard time absorbing deeply enough through the skin's outer barrier to actually reach the muscles.

So whether it truly works the way Botox does at a biological level is still up for debate, but early clinical outcomes are fairly encouraging.

A 12 week human study of a multi-ingredient regimen containing this ingredient saw:

While some studies have observed improvements in wrinkle appearance, it is important to note that more consistent results are seen in multi-ingredient formulations (vs just Acetyl Hexapeptide-8 alone).

Some research studies also used higher concentrations (up to 10%) while this ingredient is usually found in concentrations up to 0.005% in leave-on formulations.

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

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.

Caprylyl 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).

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.

You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.

The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.

Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.

Ceramide EOP is formally known as Ceramide 1.

It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.

EOP stands for a linked Ester fatty acid, a linked Omega hydroxy fatty acid, and the Phytosphingosine base.

What makes Ceramide EOP special is its ultra-long fatty acid chain; this unique structure allows it to bridge the lipid layers in your skin barrier to prevent water loss (something no other ceramide can do).

Low levels of Ceramide EOP have been found in people with eczema and psoriasis.

Using it together with other ceramides, cholesterol, and linoleic acid have been shown to meaningfully improve hydration and reduce water loss.

In one clinical study, a regimen using Ceramide EOP, NP, and AP led to significant symptom improvements in patients with eczema, psoriasis, and dry skin in just 4 weeks.

You'll usually see concentrations between 0.1-0.5% in formulations. Overall, this is a well-tolerated and safe ingredient for cosmetic use.

Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.

Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Cholesterol is a lipid that is naturally found in human skin and is one of the three key components of your skin barrier. In skincare, it is an emollient and barrier-repairing ingredient.

It works by fitting directly into the lipid layers of skin to help restore structure and reduce transepidermal water loss (TEWL).

This is a great ingredient for dry, compromised, or aging skin; our skin starts to produce less cholesterol with age.

Research shows cholesterol works best in combination with ceramides and fatty acids, the other two major components in your skin barrier.

Cholesterol is also a well-establish penetration enhancer and can help other actives absorb more effectively.

Cosmetic-grade cholesterol is usually derived from lanolin but plant and synthetic options also exist. We recommend reaching out to the brand if you have questions about their source of cholesterol.

Collagen is a big structural protein that your body uses to keep skin firm and bouncy. Despite the marketing, topically applied collagen doesn't "refill" the collagen in your skin.

The molecule is too big to pass through your skin barrier so intact Collagen physically can't get past the surface.

What it actually does in your skincare is work as a humectant and film-former: it binds water, lays down a light moisturizing film, and reduces water loss from the surface. This helps make skin feel smoother and temporarily plumper.

This ingredient has been found safe for use in cosmetics with clinical studies showing no irritation, sensitization, or phototoxicity. It's typically used at low concentrations (often a fraction of a percent up to a few percent).

Collagen will not increase sun sensitivity, but you should always wear sunscreen during the day.

Learn more about hydrolyzed collagen or soluble collagen.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Ethylhexylglycerin 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.

Glutamic Acid is an amino acid that is found in all living organisms. Our bodies use this to help nerve cells in the brain communicate with other cells.

In cosmetics, glutamic acid is a famous humectant. It draws water from the air to your skin, keeping your skin hydrated (like hyaluronic acid).

An in-vitro study from 2024 found glutamic acid to play a role in inhibiting inflammation and thus a potential skin-soothing ingredient.

Other studies show it to be have potential wound healing, skin barrier repair, and hair growth properties.

Glutamic acid has poor solubility in water and other solvents.

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.

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.

Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal.

Leuconostoc comes from lactic acid.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

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.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

Palmitoyl Tripeptide-1 (aka Pal-GHK) is a synthetic signal peptide made of three amino acids attached to palmitic acid.

That fatty acid attachment is the key: it boosts the peptide's ability to penetrate the skin barrier. This puts it closer to the dermal cells where it can actually make a difference.

Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.

In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than retinoic acid, which needed 500 ppm to do the same thing.

Human clinical data is promising, but modest:

A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.

A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.

You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.

Fungal acne note: Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

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.

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.

Phytosphingosine is a phospholipid naturally found in our skin as a building block for ceramides.. It helps moisturize, soothe, and protect skin.

Phytosphingosine contributes to your skin's natural moisturizing factor (NMF). The NMF is responsible for hydration, a strong barrier, and plasticity. Our NMF decreases with age. Increasing NMF leads to more healthy and hydrated skin.

Studies show products formulated with NMF ingredients help strengthen our skin's barrier. Having a healthy skin barrier reduces irritation and increases hydration. Our skin barrier is responsible for having plump and firm skin. It also helps protect our skin against infection, allergies, and inflammation.

Fun fact: Phytosphingosine is abundant in plants and fungi.

More ingredients that help boost collagen in skin:

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.

Propanediol 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.

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.

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.

Stearyl Alcohol is a type of fatty alcohol from stearic acid. It is a white, waxy compound used to emulsify ingredients used as an emollient or to thicken a product.

Emollients help soothe and hydrate the skin by trapping moisture.

Fatty alcohols are usually derived from natural fats and oils and therefore do not have the same drying or irritating effect as solvent (ethanol) alcohols.

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.

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.

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

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.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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Ingredients, questions
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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  7. 07Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  8. 08It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  9. 09Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  10. 10A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  11. 11Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
  12. 12You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.
  13. 13The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.
  14. 14Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.
  15. 15Ceramide EOP is formally known as Ceramide 1.
  16. 16It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.
  17. 17EOP stands for a linked Ester fatty acid, a linked Omega hydroxy fatty acid, and the Phytosphingosine base.
  18. 18What makes Ceramide EOP special is its ultra-long fatty acid chain; this unique structure allows it to bridge the lipid layers in your skin barrier to prevent water loss (something no other ceramide can do).
  19. 19Low levels of Ceramide EOP have been found in people with eczema and psoriasis.
  20. 20Using it together with other ceramides, cholesterol, and linoleic acid have been shown to meaningfully improve hydration and reduce water loss.
Source · skinsort.com
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