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Paula's Choice Peptide Booster Versus Skinfix Barrier+ Triple Lipid + Collagen + Niacinamide Activating Serum

Paula's Choice Peptide Booster Versus Skinfix Barrier+ Triple Lipid + Collagen + Niacinamide Activating Serum This anti-aging treatment is formulated around Tripeptide-1 and Palmitoyl Tripeptide-1 to soften the look of wrinkles and refine skin texture. This ba

Paula's Choice Peptide Booster Versus Skinfix Barrier+ Triple Lipid + Collagen + Niacinamide Activating Serum

This anti-aging treatment is formulated around Tripeptide-1 and Palmitoyl Tripeptide-1 to soften the look of wrinkles and refine skin texture.

This barrier-repair serum is formulated around Niacinamide and Ceramide NP to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

PEG-8 Dimethicone

Tripeptide-1

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Palmitoyl Hexapeptide-12

Myristoyl Hexapeptide-16

Myristoyl Pentapeptide-17

Hexanoyl Dipeptide-3 Norleucine Acetate

Azelaoyl Bis-Dipeptide-10

Glycoproteins

Phospholipids

Adenosine

Dipotassium Glycyrrhizate

Arginine

Valine

Glycine

Alanine

Glutamic Acid

Serine

Threonine

Yeast Extract

Isoleucine

Proline

Histidine

Phenylalanine

PCA

Phytic Acid

Panax Ginseng Root Extract

Sodium PCA

Psidium Guajava Fruit Extract

Euterpe Oleracea Fruit Extract

Ahnfeltiopsis Concinna Extract

Dextran

Hydrolyzed Silk

Lecithin

Glyceryl Polymethacrylate

C12-16 Pareth-9

Trideceth-12

Sodium Lactate

Carbomer

Aspartic Acid

Polysorbate 20

Butylene Glycol

Caprylyl Glycol

PEG-8

C11-15 Pareth-7

Guar Hydroxypropyltrimonium Chloride

Phytosteryl/Octyldodecyl Lauroyl Glutamate

Ectoin

Citrate Buffer

Trimethylsiloxyamodimethicone

Phenoxyethanol

Sodium Hydroxide

Ethylhexylglycerin

Water, Glycerin, PEG-8 Dimethicone, Tripeptide-1, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Palmitoyl Hexapeptide-12, Myristoyl Hexapeptide-16, Myristoyl Pentapeptide-17, Hexanoyl Dipeptide-3 Norleucine Acetate, Azelaoyl Bis-Dipeptide-10, Glycoproteins, Phospholipids, Adenosine, Dipotassium Glycyrrhizate, Arginine, Valine, Glycine, Alanine, Glutamic Acid, Serine, Threonine, Yeast Extract, Isoleucine, Proline, Histidine, Phenylalanine, PCA, Phytic Acid, Panax Ginseng Root Extract, Sodium PCA, Psidium Guajava Fruit Extract, Euterpe Oleracea Fruit Extract, Ahnfeltiopsis Concinna Extract, Dextran, Hydrolyzed Silk, Lecithin, Glyceryl Polymethacrylate, C12-16 Pareth-9, Trideceth-12, Sodium Lactate, Carbomer, Aspartic Acid, Polysorbate 20, Butylene Glycol, Caprylyl Glycol, PEG-8, C11-15 Pareth-7, Guar Hydroxypropyltrimonium Chloride, Phytosteryl/Octyldodecyl Lauroyl Glutamate, Ectoin, Citrate Buffer, Trimethylsiloxyamodimethicone, Phenoxyethanol, Sodium Hydroxide, Ethylhexylglycerin

Caprylyl Caprylate/Caprate

Propanediol

Jojoba Oil/Macadamia Seed Oil Esters

Niacinamide

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Squalene

Macadamia Integrifolia Seed Oil

Amylopectin

Phytosteryl Macadamiate

Collagen Amino Acids

Lithothamnion Calcareum Extract

Sodium Hyaluronate

Oligopeptide-3

Oligopeptide-2

Oligopeptide-1

Hexapeptide-11

Folic Acid

Bacillus/Soybean Ferment Extract

Lactic Acid

Ceramide NP

Phytosterols

Phytosphingosine

Ceramide AP

Cholesterol

Myrica Cerifera Fruit Extract

Akebia Quinata Stem Extract

Prunus Lannesiana Flower Extract

Saccharomyces Lysate

Lactobacillus Ferment Lysate

Ceramide EOP

Polyglutamic Acid

Tocopheryl Acetate

Tocopherol

Sodium Lauroyl Lactylate

Hexylene Glycol

Pentylene Glycol

Acetyl Glutamine

Trisodium Ethylenediamine Disuccinate

Leuconostoc/Radish Root Ferment Filtrate

Sodium Benzoate

Hydroxyacetophenone

Xanthan Gum

Potassium Sorbate

1,2-Hexanediol

Water, Caprylyl Caprylate/Caprate, Propanediol, Jojoba Oil/Macadamia Seed Oil Esters, Niacinamide, Glycerin, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Squalene, Macadamia Integrifolia Seed Oil, Amylopectin, Lecithin, Phytosteryl Macadamiate, Collagen Amino Acids, Lithothamnion Calcareum Extract, Sodium Hyaluronate, Oligopeptide-3, Oligopeptide-2, Oligopeptide-1, Hexapeptide-11, Folic Acid, Bacillus/Soybean Ferment Extract, Lactic Acid, Phospholipids, Ceramide NP, Phytosterols, Phytosphingosine, Ceramide AP, Cholesterol, Myrica Cerifera Fruit Extract, Akebia Quinata Stem Extract, Prunus Lannesiana Flower Extract, Saccharomyces Lysate, Lactobacillus Ferment Lysate, Tripeptide-1, Ceramide EOP, Polyglutamic Acid, Tocopheryl Acetate, Tocopherol, Butylene Glycol, Caprylyl Glycol, Sodium Lauroyl Lactylate, Ethylhexylglycerin, Hexylene Glycol, Pentylene Glycol, Acetyl Glutamine, Trisodium Ethylenediamine Disuccinate, Leuconostoc/Radish Root Ferment Filtrate, Sodium Benzoate, Hydroxyacetophenone, Xanthan Gum, Potassium Sorbate, Carbomer, 1,2-Hexanediol, Dextran, Phenoxyethanol

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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.

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.

Dextran is a sugar (polysaccharide) with skin hydrating properties.

Fun fact: Louis Pasteur first discovered this ingredient as a microbial product in wine.

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.

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.

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.

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.

Phospholipids are a family of skin-identical lipids that makeup the structural backbone of every cell membrane in your body.

In cosmetics, they function as skin conditioning agents with emulsifier and surfactant properties. They're typically sourced from soybean or sunflower lecithin (or sometimes egg yolk or marine sources).

Because they mirror the lipids naturally found in the deeper layers of your skin, topical phospholipids help reinforce the lipid matrix, reduce transepidermal water loss, and leave skin feeling conditioned.

They're also used to form liposomes, or tiny self-assembling vesible used to stabilize actives like vitamin c or retinol. This helps these ingredients integrate into the upper layers of skin more easily.

Phospholipids are compatible with everything and the CIR Expert Panel has concluded them to be safe at current use levels.

Some types of phospholipids include:

Tripeptide-1, also known as GHK), is a small, three-amino-acid peptide made up of glycine, histidine, and lysine.

This ingredient is a signal peptide and tell your skin to start producing fresh collagen, elastin, and other key structural proteins. This helps maintain firmness and reduces the look of fine-lines/wrinkles.

GHK is also unique because is also acts as a carrier peptide. It binds to and transports copper ions (forming the complex GHK-Cu). This form has been studied for decades and is known to stimulate wound healing, boost antioxidant defenses, and promote collagen/elastin synthesis.

In-vitro studies show both GHK and GHK-CU increase fibroblast activity that enhances the production of collagen, elastin, fibronectin, and other extracellular matrix components.

Both of these compounds also help balance enzymes that control collagen breakdown.

Human studies (in-vivo) using GHK-Cu creams have reported visible improvements to skin density, elasticity, and wrinkle depth after several weeks of use.

A small clinical study also found topical collagen tripeptide improved wrinkle appearance and skin elasticity in women after four weeks.

While these results are promising, most research is based on GHK-Cu or its derivatives rather than Tripeptide-1 alone (Palmitoyl Tripeptide-1 is a famous derivative of GHK). However, the consensus still supports GHK as a potent skin-signaling molecule that can encourage regeneration and maintain youthful looking skin.

Fun fact: GHK is a naturally occurring fragment of type 1 collagen that can be found in human plasma, saliva, and urine.

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 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. 06Dextran is a sugar (polysaccharide) with skin hydrating properties.
  7. 07Fun fact: Louis Pasteur first discovered this ingredient as a microbial product in wine.
  8. 08Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  9. 09The 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 …
  10. 10Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  11. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your 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.
  14. 14Aquaporin-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.
  15. 15This 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.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  19. 19It 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.
  20. 20On 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.
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice Peptide Booster

Paula's Choice Peptide Booster Paula's Choice Peptide Booster ingredients explained: Water (Aqua), Glycerin, Peg-8 Dimethicone, Tripeptide-1, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side