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Peter Thomas Roth FIRMx Collagen Serum Versus First Aid Beauty Ultra Repair Face Moisturizer

Peter Thomas Roth FIRMx Collagen Serum Versus First Aid Beauty Ultra Repair Face Moisturizer This anti-aging serum is formulated around Palmitoyl Tripeptide-5 to soften the look of wrinkles. This barrier-repair moisturizer is formulated around Avena Sativa Ker

Peter Thomas Roth FIRMx Collagen Serum Versus First Aid Beauty Ultra Repair Face Moisturizer

This anti-aging serum is formulated around Palmitoyl Tripeptide-5 to soften the look of wrinkles.

This barrier-repair moisturizer is formulated around Avena Sativa Kernel Flour and Squalane to strengthen the skin barrier and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Collagen

Water

Dimethicone

Butylene Glycol

Polysilicone-11

Glycerin

Caffeine

Squalane

Soluble Collagen

Collagen Amino Acids

Hydrolyzed Collagen

Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine

Palmitoyl Tripeptide-5

Acetyl Tetrapeptide-2

Sodium Hyaluronate

Hydroxyproline

Sodium Citrate

Citric Acid

Acrylamide/Sodium Acryloyldimethyltaurate Copolymer

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Hydroxystearic Acid

Magnesium Chloride

Polysorbate 20

Polysorbate 80

Sodium Hydroxide

Sorbitan Isostearate

Decyl Glucoside

Lauryl Glucoside

Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate

Leuconostoc/Radish Root Ferment Filtrate

Disodium EDTA

Potassium Sorbate

Sodium Benzoate

Isohexadecane

Ethylhexylglycerin

Hexylene Glycol

Caprylyl Glycol

Phenoxyethanol

Mica

Collagen, Water, Dimethicone, Butylene Glycol, Polysilicone-11, Glycerin, Caffeine, Squalane, Soluble Collagen, Collagen Amino Acids, Hydrolyzed Collagen, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Palmitoyl Tripeptide-5, Acetyl Tetrapeptide-2, Sodium Hyaluronate, Hydroxyproline, Sodium Citrate, Citric Acid, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Hydroxystearic Acid, Magnesium Chloride, Polysorbate 20, Polysorbate 80, Sodium Hydroxide, Sorbitan Isostearate, Decyl Glucoside, Lauryl Glucoside, Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate, Leuconostoc/Radish Root Ferment Filtrate, Disodium EDTA, Potassium Sorbate, Sodium Benzoate, Isohexadecane, Ethylhexylglycerin, Hexylene Glycol, Caprylyl Glycol, Phenoxyethanol, Mica

Glyceryl Stearate Se

Caprylic/Capric Triglyceride

Urea

Cetyl Alcohol

Avena Sativa Kernel Flour

Butyrospermum Parkii Butter

Allantoin

Persea Gratissima Oil

N-Butyl Alcohol

Carbomer

Chrysanthemum Parthenium Extract

Camellia Sinensis Leaf Extract

Glycyrrhiza Glabra Root Extract

Ceramide NP

Tetrasodium EDTA

Water, Glyceryl Stearate Se, Glycerin, Caprylic/Capric Triglyceride, Dimethicone, Urea, Cetyl Alcohol, Avena Sativa Kernel Flour, Squalane, Caprylyl Glycol, Butyrospermum Parkii Butter, Allantoin, Persea Gratissima Oil, N-Butyl Alcohol, Carbomer, Chrysanthemum Parthenium Extract, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Sodium Hydroxide, Ceramide NP, Leuconostoc/Radish Root Ferment Filtrate, Phenoxyethanol, Tetrasodium EDTA

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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.

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).

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.

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.

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).

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 Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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!

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

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. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.
  6. 06A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.
  7. 07Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  8. 08Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  9. 09Though 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.
  10. 10This 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.
  11. 11Because 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).
  12. 12In 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!).
  13. 13Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
  14. 14Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
  15. 15While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
  16. 16This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
  17. 17Caprylic/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.
  18. 18Though 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.
  19. 19In practice, that translates to a long shelf life and a consistently elegant skin feel.
  20. 20While 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.
Source · skinsort.com
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