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Peter Thomas Roth Pro Strength Vitamin A/C/E Retinoid Treatment Versus Paula's Choice C5 Super Boost Moisturizer

Peter Thomas Roth Pro Strength Vitamin A/C/E Retinoid Treatment Versus Paula's Choice C5 Super Boost Moisturizer This anti-aging treatment is formulated around Tocopheryl Acetate and Hydroxypinacolone Retinoate to soften the look of wrinkles and refine skin te

Peter Thomas Roth Pro Strength Vitamin A/C/E Retinoid Treatment Versus Paula's Choice C5 Super Boost Moisturizer

This anti-aging treatment is formulated around Tocopheryl Acetate and Hydroxypinacolone Retinoate to soften the look of wrinkles and refine skin texture.

This brightening moisturizer is formulated around 3-O-Ethyl Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dimethyl Isosorbide

Tocopheryl Acetate

Isononyl Isononanoate

Caprylic/Capric Triglyceride

Propanediol

Pentylene Glycol

Dimethicone

C9-12 Alkane

Glyceryl Stearate

Volcanic Soil

Cetyl Alcohol

Hydroxypinacolone Retinoate

Butyrospermum Parkii Butter

Caprylyl Methicone

Ascorbic Acid

Citric Acid

Squalane

Sodium Hyaluronate

Amylopectin

Ethylhexylglycerin

Coco-Caprylate/Caprate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Sodium Phytate

Diethylhexyl Syringylidenemalonate

Potassium Sorbate

PEG-75 Stearate

Polyacrylate Crosspolymer-6

PEG-100 Stearate

Silica

Ceteth-20

Steareth-20

1,2-Hexanediol

Sodium Benzoate

Polysorbate 60

T-Butyl Alcohol

Sorbitan Isostearate

Phenoxyethanol

Water, Dimethyl Isosorbide, Tocopheryl Acetate, Isononyl Isononanoate, Caprylic/Capric Triglyceride, Propanediol, Pentylene Glycol, Dimethicone, C9-12 Alkane, Glyceryl Stearate, Volcanic Soil, Cetyl Alcohol, Hydroxypinacolone Retinoate, Butyrospermum Parkii Butter, Caprylyl Methicone, Ascorbic Acid, Citric Acid, Squalane, Sodium Hyaluronate, Amylopectin, Ethylhexylglycerin, Coco-Caprylate/Caprate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Sodium Phytate, Diethylhexyl Syringylidenemalonate, Potassium Sorbate, PEG-75 Stearate, Polyacrylate Crosspolymer-6, PEG-100 Stearate, Silica, Ceteth-20, Steareth-20, 1,2-Hexanediol, Sodium Benzoate, Polysorbate 60, T-Butyl Alcohol, Sorbitan Isostearate, Phenoxyethanol

Dicaprylyl Carbonate

3-O-Ethyl Ascorbic Acid

Butylene Glycol

Polyglyceryl-6 Distearate

Ascorbyl Glucoside

Acetyl Sh-Hexapeptide-5 Amide Acetate

Citrullus Lanatus Seed Oil

Hydrogenated Lecithin

Theobroma Cacao Seed Butter

Hydrogenated Phosphatidylcholine

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Oryza Sativa Bran Extract

Jojoba Esters

Tocopherol

Acetyl Zingerone

Cetyl Palmitate

Caprylyl Glycol

Polyglyceryl-3 Beeswax

Sodium Hydroxide

Sorbitan Olivate

Sorbitan Palmitate

Helianthus Annuus Extract

Hexylene Glycol

Lecithin

Rosmarinus Officinalis Leaf Extract

Glycine Soja Oil

Lysolecithin

Bacillus Ferment

Polyglutamic Acid

Beta-Sitosterol

Phytic Acid

Squalene

Water, Dicaprylyl Carbonate, 3-O-Ethyl Ascorbic Acid, Dimethicone, Butylene Glycol, Polyglyceryl-6 Distearate, Ascorbyl Glucoside, Squalane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Acetyl Sh-Hexapeptide-5 Amide Acetate, Citrullus Lanatus Seed Oil, Hydrogenated Lecithin, Theobroma Cacao Seed Butter, Hydrogenated Phosphatidylcholine, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Hyaluronate, Oryza Sativa Bran Extract, Propanediol, Jojoba Esters, Tocopherol, Acetyl Zingerone, Cetyl Palmitate, Caprylyl Glycol, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Sodium Hydroxide, Sorbitan Olivate, Sorbitan Palmitate, Helianthus Annuus Extract, Ethylhexylglycerin, Hexylene Glycol, Sodium Phytate, Polysorbate 60, Sorbitan Isostearate, Lecithin, Rosmarinus Officinalis Leaf Extract, Glycine Soja Oil, Lysolecithin, Bacillus Ferment, Citric Acid, Polyglutamic Acid, Beta-Sitosterol, Phytic Acid, Squalene, Phenoxyethanol, Sodium Benzoate, Potassium Sorbate

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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.

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.

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.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

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.

This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.

It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.

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.

Polysorbate 60 is used to help stabilize products. It is a surfactant and emulsifier. These properties help keep ingredients together in a product. Surfactants help reduce surface tension between ingredients with different states, such as liquids and solids. Emulsifiers help prevent oils and waters from separating.

Polysorbate 60 is sorbitol-based and created from the ethoxylation of sorbitan. Ethoxylation is a chemical reaction used to add ethylene oxide. Sorbitan is a the dehydrated version of sorbitol, a sugar found in fruits.

In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.

Polysorbates are commonly used in medicine and foods.

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.

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.

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.

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 Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.

Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.

Sorbitan Isostearate is an emulsifer. It is created from isostearic acid and sorbitol.

As an emulsifier, it keeps the water and oil ingredients from separating. This keeps formulas stable and smooth.

In a 24 hour occlusive patch test on 56 subjects, 10% sorbitan isostearate was completely non-irritating. Most formulas use less than 10%.

Because it's a fatty acid ester, it may not be fungal acne safe since the Malassezia yeast can utilize it as a nutrient source.

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.

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!

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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 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. 03Arginine 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.
  4. 04It 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.
  5. 05Here'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.
  6. 06A 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.
  7. 07Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.
  8. 08One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.
  9. 09Arginine 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.
  10. 10Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  11. 11Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  12. 12Though 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.
  13. 13This ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.
  14. 14Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).
  15. 15In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).
  16. 16Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
  17. 17Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
  18. 18While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
  19. 19This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
  20. 20Carbomer 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.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

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