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Skin science article

Paula's Choice C15 Super Booster Versus Paula's Choice Peptide Booster

Paula's Choice C15 Super Booster Versus Paula's Choice Peptide Booster This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. This anti-aging treatment is formulated around Trip

Paula's Choice C15 Super Booster Versus Paula's Choice Peptide Booster

This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Ascorbic Acid

Dipropylene Glycol

Propanediol

Glycerin

Ethoxydiglycol

Sodium Hydroxide

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Bisabolol

Ferulic Acid

Sodium Phytate

Decylene Glycol

Tocopherol

1,2-Hexanediol

Sphingomonas Ferment Extract

Phenoxyethanol

Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol

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

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

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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.

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.

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.

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.

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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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  7. 07Like 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.
  8. 08However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  9. 09Due 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.
  10. 10In skincare formulas, citric acid can:
  11. 11While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  12. 12Most 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.
  13. 13Rosacea 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.
  14. 14However, 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…
  15. 15Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.
  16. 16This ingredient mainly works behind the scenes and helps with:
  17. 17On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.
  18. 18One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too st…
  19. 19Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.
  20. 20You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.
Source · skinsort.com
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Product index

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Comparison edit

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