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Peter Thomas Roth PRO Strength Retinoid Peptide Serum Versus Drunk Elephant Protini Powerpeptide Resurfacing Serum

Peter Thomas Roth PRO Strength Retinoid Peptide Serum Versus Drunk Elephant Protini Powerpeptide Resurfacing Serum This anti-aging serum is formulated around Hydroxypinacolone Retinoate and Ceramide NP to soften the look of wrinkles and refine skin texture. Th

Peter Thomas Roth PRO Strength Retinoid Peptide Serum Versus Drunk Elephant Protini Powerpeptide Resurfacing Serum

This anti-aging serum is formulated around Hydroxypinacolone Retinoate and Ceramide NP to soften the look of wrinkles and refine skin texture.

This smoothing serum is formulated around Lactic Acid and Sh-Oligopeptide-1 to refine skin texture and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

C9-12 Alkane

Dimethicone

Isononyl Isononanoate

Dimethyl Isosorbide

Trisiloxane

Cyclopentasiloxane

Polysilicone-11

Coco-Caprylate/Caprate

Caprylic/Capric Triglyceride

Hydroxypinacolone Retinoate

Palmitoyl Hexapeptide-14

Ceramide NP

Helianthus Annuus Seed Extract

Hordeum Vulgare Extract

Cucumis Sativus Extract

Laminaria Ochroleuca Extract

Zingiber Officinale Root Extract

Phytosteryl Canola Glycerides

Sodium Hyaluronate

Sodium PCA

Squalane

Tocopherol

Lecithin

Linoleic Acid

Oleic Acid

Palmitic Acid

Stearic Acid

Hydroxystearic Acid

Triolein

Bisabolol

Ethylhexyl Hydroxystearate

Ethoxydiglycol

Ethylhexylglycerin

Water

Mica

Phenoxyethanol

C9-12 Alkane, Dimethicone, Isononyl Isononanoate, Dimethyl Isosorbide, Trisiloxane, Cyclopentasiloxane, Polysilicone-11, Coco-Caprylate/Caprate, Caprylic/Capric Triglyceride, Hydroxypinacolone Retinoate, Palmitoyl Hexapeptide-14, Ceramide NP, Helianthus Annuus Seed Extract, Hordeum Vulgare Extract, Cucumis Sativus Extract, Laminaria Ochroleuca Extract, Zingiber Officinale Root Extract, Phytosteryl Canola Glycerides, Sodium Hyaluronate, Sodium PCA, Squalane, Tocopherol, Lecithin, Linoleic Acid, Oleic Acid, Palmitic Acid, Stearic Acid, Hydroxystearic Acid, Triolein, Bisabolol, Ethylhexyl Hydroxystearate, Ethoxydiglycol, Ethylhexylglycerin, Water, Mica, Phenoxyethanol

Glycerin

Lactic Acid

Dicaprylyl Carbonate

Sodium Hydroxide

Glycine Max Seed Extract

Sclerocarya Birrea Seed Oil

Camellia Sinensis Seed Oil

Borago Officinalis Seed Oil

Tremella Fuciformis Polysaccharide

Tocotrienols

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

Palmitoyl Tripeptide-38

Palmitoyl Hexapeptide-12

Tripeptide-1

Pyrus Malus Fruit Extract

Propanediol

Panthenol

Sodium Hyaluronate Crosspolymer

Sodium Lactate

PCA

Alanine

Arginine

Glycine

Histidine

Isoleucine

Phenylalanine

Proline

Serine

Threonine

Valine

Adenosine

Nymphaea Alba Root Extract

Bacillus/Folic Acid Ferment Filtrate Extract

Symphytum Officinale Callus Culture Extract

Dextran

Oryza Sativa Bran Oil

Linolenic Acid

Butylene Glycol

Acetyl Glutamine

Coconut Alkanes

Pentylene Glycol

Isomalt

Xanthan Gum

Aspartic Acid

Phytosphingosine

Phospholipids

Glycine Soja Sterols

Citric Acid

Lactic Acid/Glycolic Acid Copolymer

Polyvinyl Alcohol

Sodium Benzoate

Hydroxypropyl Cyclodextrin

Polysorbate 20

Caprylyl Glycol

Phenylpropanol

Chlorphenesin

Carbomer

Glyceryl Caprylate

Water, Glycerin, Lactic Acid, Dicaprylyl Carbonate, Squalane, Sodium Hydroxide, Glycine Max Seed Extract, Sclerocarya Birrea Seed Oil, Camellia Sinensis Seed Oil, Sodium PCA, Caprylic/Capric Triglyceride, Borago Officinalis Seed Oil, Tremella Fuciformis Polysaccharide, Tocotrienols, 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, Palmitoyl Tripeptide-38, Palmitoyl Hexapeptide-12, Tripeptide-1, Pyrus Malus Fruit Extract, Propanediol, Sodium Hyaluronate, Panthenol, Sodium Hyaluronate Crosspolymer, Sodium Lactate, PCA, Alanine, Arginine, Glycine, Histidine, Isoleucine, Phenylalanine, Proline, Serine, Threonine, Valine, Adenosine, Nymphaea Alba Root Extract, Bacillus/Folic Acid Ferment Filtrate Extract, Symphytum Officinale Callus Culture Extract, Dextran, Oryza Sativa Bran Oil, Linoleic Acid, Linolenic Acid, Butylene Glycol, Acetyl Glutamine, Coconut Alkanes, Coco-Caprylate/Caprate, Pentylene Glycol, Isomalt, Lecithin, Xanthan Gum, Aspartic Acid, Phytosphingosine, Phospholipids, Glycine Soja Sterols, Tocopherol, Citric Acid, Lactic Acid/Glycolic Acid Copolymer, Polyvinyl Alcohol, Phenoxyethanol, Sodium Benzoate, Hydroxypropyl Cyclodextrin, Polysorbate 20, Caprylyl Glycol, Phenylpropanol, Chlorphenesin, Carbomer, Glyceryl Caprylate, Ethylhexylglycerin

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

Coco-Caprylate/Caprate is a lightweight ester created from coconut oil fatty acids, caprylic acid, and capric acid.

It is an emollient that helps soften skin and reduce transepidermal water loss (TEWL). What sets it apart from heavier emollients is its ultralight, non-greasy feel.

Once applied, this ingredient dries down quickly and leaves a dry, silky finish behind. This also helps improve spreadability and texture.

This ingredient has an excellent safety-record and is non-irritating.

Typical concentrations for cosmetics range from 0.5-62%.

Research on Malassezia growth found no growth on fatty acid esters with chain lengths shorter than 12 carbons (it prefers C11-24).

Since Coco-Caprylate/Caprate is built on C8 and C10 fatty acids, it is out of the range that Malassezia metabolizes, and therefore safe for fungal acne.

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.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

Linoleic Acid is also known as Vitamin F. It is a fatty acid with emollient and skin conditioning properties.

Our top layer of skin, or epidermis, naturally contains high amounts of linoleic acid.

Your body uses linoleic acid to build ceramides and prostaglandins. Ceramides keep your skin's barrier hydrated and strong while prosaglandins help control inflammation and healing.

Needless to say, linoleic acid is crucial for having a strong skin barrier.

One study found applying linoleic acid rich sunflower oil to be more effective at repairing the skin barrier than olive oil.

This ingredient can also help treat acne by softening sebum to prevent clogged pores. Another study found using 2.5% linoleic acid gel for 4 weeks showed a 25% reduction in small comedones.

Studies show it can also help lighten hyperpigmentation or sun spots by disrupting the melanin production process. It also helps your skin shed melanin pigment from your skin caused by UV exposure.

Due to its role in the production of the fatty acid prostaglandin, linoleic acid can also help reduce inflammation and support wound healing.

Fun fact: Linoleic acid is an essential fatty acid. This means our bodies cannot create it on its own and we need to get it through foods such as nuts and vegetable oils.

Just know this ingredient is not always fungal-acne safe because it is a long-chain fatty acid (with 18 carbon atoms) that directly feeds the Malassezia yeast responsible for fungal acne.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

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 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%.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

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.

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Formula cabinet

Ingredients & structured notes

02

Product index

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Comparison edit

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