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Medik8 Crystal Retinal 10 Versus Paula's Choice C15 Super Booster

Medik8 Crystal Retinal 10 Versus Paula's Choice C15 Super Booster This anti-aging serum is formulated around Retinal and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. This brightening serum is formulated around Ascorbic Acid

Medik8 Crystal Retinal 10 Versus Paula's Choice C15 Super Booster

This anti-aging serum is formulated around Retinal and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Caprylic/Capric Triglyceride

Glycerin

Isododecane

Cetearyl Olivate

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Cetearyl Alcohol

PPG-12/Smdi Copolymer

Sorbitan Olivate

Tocopheryl Acetate

Titanium Dioxide

Eclipta Prostrata Extract

Cyclodextrin

Squalane

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Phenoxyethanol

Melia Azadirachta Leaf Extract

Hydroxypropyl Methylcellulose

Sodium Hyaluronate

Tetrahexyldecyl Ascorbate

Rubus Chamaemorus Seed Oil

Alumina

Isostearic Acid

Lecithin

Polyglyceryl-3 Polyricinoleate

Polyhydroxystearic Acid

Stearic Acid

Pentylene Glycol

Retinal

Moringa Oleifera Seed Oil

Sodium Polyaspartate

Climbazole

Disodium EDTA

Lonicera Japonica Flower Extract

Lonicera Caprifolium Flower Extract

Daucus Carota Sativa Seed Oil

Ethylhexylglycerin

3-O-Ethyl Ascorbic Acid

Dipteryx Odorata Bean Extract

Hydroxyacetophenone

Polysorbate 60

Sorbitan Isostearate

Vanilla Planifolia Fruit Extract

Decylene Glycol

1,2-Hexanediol

BHT

Coumarin

Water, Caprylic/Capric Triglyceride, Glycerin, Isododecane, Cetearyl Olivate, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Cetearyl Alcohol, PPG-12/Smdi Copolymer, Sorbitan Olivate, Tocopheryl Acetate, Titanium Dioxide, Eclipta Prostrata Extract, Cyclodextrin, Squalane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Phenoxyethanol, Melia Azadirachta Leaf Extract, Hydroxypropyl Methylcellulose, Sodium Hyaluronate, Tetrahexyldecyl Ascorbate, Rubus Chamaemorus Seed Oil, Alumina, Isostearic Acid, Lecithin, Polyglyceryl-3 Polyricinoleate, Polyhydroxystearic Acid, Stearic Acid, Pentylene Glycol, Retinal, Moringa Oleifera Seed Oil, Sodium Polyaspartate, Climbazole, Disodium EDTA, Lonicera Japonica Flower Extract, Lonicera Caprifolium Flower Extract, Daucus Carota Sativa Seed Oil, Ethylhexylglycerin, 3-O-Ethyl Ascorbic Acid, Dipteryx Odorata Bean Extract, Hydroxyacetophenone, Polysorbate 60, Sorbitan Isostearate, Vanilla Planifolia Fruit Extract, Decylene Glycol, 1,2-Hexanediol, BHT, Coumarin

Ascorbic Acid

Dipropylene Glycol

Propanediol

Ethoxydiglycol

Sodium Hydroxide

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Bisabolol

Ferulic Acid

Sodium Phytate

Tocopherol

Sphingomonas Ferment Extract

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

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

We don't have a description for Decylene Glycol yet.

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.

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. 03Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.
  4. 04This ingredient mainly works behind the scenes and helps with:
  5. 05On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.
  6. 06One 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…
  7. 07Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.
  8. 08You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.
  9. 09Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  10. 10Topically, glycerin does several things at once:
  11. 11Your 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.
  12. 12Aquaporin-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.
  13. 13This 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.
  14. 14Just know very high concentrations (>40%) can feel tacky in low humidity.
  15. 15Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  16. 16Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.
  17. 17And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.
  18. 18You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.
  19. 19In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.
  20. 20If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.
Source · skinsort.com
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Comparison edit

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