Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Neutrogena Hydro Boost Gel Crème Versus Drunk Elephant Protini Polypeptide Cream

Neutrogena Hydro Boost Gel Crème Versus Drunk Elephant Protini Polypeptide Cream This barrier-repair moisturizer is formulated around Allantoin and Ceramide NP to strengthen the skin barrier and hydrate skin. This anti-aging moisturizer is formulated around Sc

Neutrogena Hydro Boost Gel Crème Versus Drunk Elephant Protini Polypeptide Cream

This barrier-repair moisturizer is formulated around Allantoin and Ceramide NP to strengthen the skin barrier and hydrate skin.

This anti-aging moisturizer is formulated around Sclerocarya Birrea Seed Oil and Sh-Oligopeptide-1 to soften the look of wrinkles and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Isopropyl Palmitate

Cetyl Alcohol

Cetearyl Olivate

Sorbitan Olivate

Alanine

Maltose

Glycine

Allantoin

Lidocaine Hcl

Arginine

Serine

Proline

Threonine

Ethylhexylglycerin

Pentylene Glycol

Ceramide NP

Tropolone

Sodium Hyaluronate

1,2-Hexanediol

Caprylyl Glycol

Trehalose

Betaine

Urea

Fructose

Glucose

PCA

Sodium PCA

Glutamic Acid

Sodium Lactate

Palmitic Acid

Stearic Acid

Dimethicone

Sodium Chloride

Polyacrylate Crosspolymer-6

C10-30 Cholesterol/Lanosterol Esters

T-Butyl Alcohol

Sodium Hydroxide

Citric Acid

Tocopherol

Water, Glycerin, Isopropyl Palmitate, Cetyl Alcohol, Cetearyl Olivate, Sorbitan Olivate, Alanine, Maltose, Glycine, Allantoin, Lidocaine Hcl, Arginine, Serine, Proline, Threonine, Ethylhexylglycerin, Pentylene Glycol, Ceramide NP, Tropolone, Sodium Hyaluronate, 1,2-Hexanediol, Caprylyl Glycol, Trehalose, Betaine, Urea, Fructose, Glucose, PCA, Sodium PCA, Glutamic Acid, Sodium Lactate, Palmitic Acid, Stearic Acid, Dimethicone, Sodium Chloride, Polyacrylate Crosspolymer-6, C10-30 Cholesterol/Lanosterol Esters, T-Butyl Alcohol, Sodium Hydroxide, Citric Acid, Tocopherol

Dicaprylyl Carbonate

Cetearyl Alcohol

Sclerocarya Birrea Seed Oil

Bacillus/Folic Acid Ferment Filtrate Extract

Nymphaea Alba Root Extract

Sh-Oligopeptide-1

Sh-Oligopeptide-2

Sh-Polypeptide-1

Sh-Polypeptide-9

Sh-Polypeptide-11

Copper Palmitoyl Heptapeptide-14

Heptapeptide-15 Palmitate

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Histidine

Isoleucine

Phenylalanine

Valine

Acetyl Glutamine

Coconut Alkanes

Coco-Caprylate/Caprate

Aspartic Acid

Linoleic Acid

Linolenic Acid

Lecithin

Butylene Glycol

Polyvinyl Alcohol

Sorbitan Isostearate

Carbomer

Polysorbate 20

Polysorbate 60

Lactic Acid/Glycolic Acid Copolymer

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Xanthan Gum

Isomalt

Chlorphenesin

Phenoxyethanol

Sodium Benzoate

Phenylpropanol

Glyceryl Caprylate

Symphytum Officinale Callus Culture Extract

Water, Dicaprylyl Carbonate, Glycerin, Cetearyl Alcohol, Cetearyl Olivate, Sorbitan Olivate, Sclerocarya Birrea Seed Oil, Bacillus/Folic Acid Ferment Filtrate Extract, Nymphaea Alba Root Extract, Sh-Oligopeptide-1, Sh-Oligopeptide-2, Sh-Polypeptide-1, Sh-Polypeptide-9, Sh-Polypeptide-11, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Alanine, Arginine, Glycine, Histidine, Isoleucine, Phenylalanine, Proline, Serine, Threonine, Valine, Acetyl Glutamine, Coconut Alkanes, Coco-Caprylate/Caprate, Sodium Hyaluronate, Aspartic Acid, Linoleic Acid, Linolenic Acid, Lecithin, Butylene Glycol, Polyvinyl Alcohol, Sodium Lactate, Sodium PCA, PCA, Sorbitan Isostearate, Carbomer, Polysorbate 20, Polysorbate 60, Lactic Acid/Glycolic Acid Copolymer, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Xanthan Gum, Isomalt, 1,2-Hexanediol, Caprylyl Glycol, Chlorphenesin, Phenoxyethanol, Tocopherol, Sodium Benzoate, Phenylpropanol, Glyceryl Caprylate, Symphytum Officinale Callus Culture Extract

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

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

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

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.

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).

Cetearyl Olivate is a plant-derived emulsifier and texture enhancer. It helps keep the oil and water phases from separating so your formulas stay stable.

You'll likely see it combined with Sorbitan Olivate (together sold as the trade name Olivem 1000). This combination generates a liquid crystal structure that closely resemble the lipid organization of the stratum corneum.

These "skin-like" liquid crystals improve skin barrier integrity and promote the delivery of actives into the skin.

This ingredient is well-tolerated and has no significant sensitization data.

Because it is derived from the fatty acids in olive oil, this ingredient may not be fungal acne safe.

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.

PCA is an amino acid derivative and one of the star players in your skin's own Natural Moisturizing Factor (NMF).

The NMF is the built-in cocktail of small molecules that keeps your outer layer of skin hydrated and your body makes it naturally.

This is why it works so well topically; PCA is a humectant that holds water in the stratum corneum and studies link higher skin PCA levels to better hydration + lower water loss. Interestingly, people show more PCA in summer and in normal vs dry skin.

Most of the benefits of this ingredient are related to hydration, softness, and barrier support.

A long-running review found that formulas with at least 2% PCA or its salts improved dry skin over both the short and long term. And the zinc salt is also used for its mild antimicrobial and astringent properties.

The salt forms are more common in cosmetics (like sodium PCA).

This ingredient is compatible with basically everything and pairs well with other humectants like glycerin or hyaluronic acid.

Usage-wise, it's typically used at low percentages (~0.2-2%).

The Cosmetic Ingredient Review Expert Panel has concluded PCA and its salts are safe as used and is non-irritating on skin even at high concentrations.

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.

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.

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.

Sodium PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

Sorbitan Olivate is created from the fatty acids in olive oil and sorbitol.

This ingredient is an oil in water emulsifier. It helps stabilize a product by preventing oils and waters from separating. Sorbitan Olivate also helps hydrate the skin.

This ingredient is also known as part of Olivem 1000, with Cetearyl Olivate being the other part.

According to a manufacturer, this ingredient helps preserve the natural microbiome of skin. Having a healthy microbiome helps keep our skin healthy and protects against harmful bacteria.

Please note, having a healthy microbiome is different from fungal acne; a healthy microbiome includes small amounts of yeast that normally live on your skin without causing problems.

Fungal acne happens when one type of yeast (Malassezia) grows out of control. This is usually because it's feeding on certain oils or fatty acids. Due to the olive oil base, this ingredient may not be fungal acne safe.

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.

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.

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!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Dicaprylyl Carbonate
  3. 03Glycerin
  4. 04Cetearyl Alcohol
  5. 05Cetearyl Olivate
  6. 06Sorbitan Olivate
  7. 07Sclerocarya Birrea Seed Oil
  8. 08Bacillus/Folic Acid Ferment Filtrate Extract
  9. 09Nymphaea Alba Root Extract
  10. 10Sh-Oligopeptide-1
  11. 11Sh-Oligopeptide-2
  12. 12Sh-Polypeptide-1
  13. 13Sh-Polypeptide-9
  14. 14Sh-Polypeptide-11
  15. 15Copper Palmitoyl Heptapeptide-14
  16. 16Heptapeptide-15 Palmitate
  17. 17Palmitoyl Tetrapeptide-7
  18. 18Palmitoyl Tripeptide-1
  19. 19Alanine
  20. 20Arginine
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side