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Medik8 Crystal Retinal 10 Versus Paula's Choice 1% Retinol Treatment

Medik8 Crystal Retinal 10 Versus Paula's Choice 1% Retinol Treatment This anti-aging serum is formulated around Retinal and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. This anti-aging treatment is formulated around Retinol

Medik8 Crystal Retinal 10 Versus Paula's Choice 1% Retinol Treatment

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

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

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

Dimethicone

Butylene Glycol

Isononyl Isononanoate

Castor Isostearate Succinate

Glyceryl Stearate

C12-15 Alkyl Benzoate

Dimethicone Crosspolymer

PEG-33

Polysorbate 20

Behenyl Alcohol

PEG-100 Stearate

Pentaerythrityl Tetraisostearate

Polymethylsilsesquioxane

Retinol

Ceramide Ng

Palmitoyl Tetrapeptide-7

Palmitoyl Hexapeptide-12

Dipotassium Glycyrrhizate

Glycyrrhiza Glabra Root Extract

Avena Sativa Kernel Extract

Arctium Lappa Seed Oil

Salix Alba Extract

Glycine Soja Sterols

Allantoin

Hydrolyzed Soy Protein

Sorbitan Laurate

Acetyl Dipeptide-1 Cetyl Ester

Hydroxyethylcellulose

Palmitoyl Tripeptide-1

Sodium Hydroxide

Tribehenin

Caprylyl Glycol

PEG-75 Shea Butter Glycerides

PEG-10 Phytosterol

PEG-8 Dimethicone

PEG-14

Magnesium Aluminum Silicate

Arachidyl Glucoside

Arachidyl Alcohol

Sclerotium Gum

Carbomer

Benzoic Acid

Water, Dimethicone, Glycerin, Butylene Glycol, Isononyl Isononanoate, Castor Isostearate Succinate, Glyceryl Stearate, C12-15 Alkyl Benzoate, Dimethicone Crosspolymer, PEG-33, Polysorbate 20, Behenyl Alcohol, PEG-100 Stearate, Pentaerythrityl Tetraisostearate, Polymethylsilsesquioxane, Tetrahexyldecyl Ascorbate, Retinol, Ceramide Ng, Palmitoyl Tetrapeptide-7, Palmitoyl Hexapeptide-12, Sodium Hyaluronate, Dipotassium Glycyrrhizate, Glycyrrhiza Glabra Root Extract, Avena Sativa Kernel Extract, Arctium Lappa Seed Oil, Salix Alba Extract, Glycine Soja Sterols, Lecithin, Allantoin, Tocopheryl Acetate, Hydrolyzed Soy Protein, Sorbitan Laurate, Acetyl Dipeptide-1 Cetyl Ester, Disodium EDTA, Hydroxyethylcellulose, Palmitoyl Tripeptide-1, Sodium Hydroxide, Tribehenin, Caprylyl Glycol, Ethylhexylglycerin, Pentylene Glycol, PEG-75 Shea Butter Glycerides, PPG-12/Smdi Copolymer, PEG-10 Phytosterol, PEG-8 Dimethicone, PEG-14, Magnesium Aluminum Silicate, Arachidyl Glucoside, Arachidyl Alcohol, Sclerotium Gum, Carbomer, Phenoxyethanol, Benzoic Acid

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.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One 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 strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

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.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

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.

We don't have a description for PPG-12/Smdi Copolymer yet.

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.

Tetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.

THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).

Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.

Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.

Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.

A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).

While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.

THD is pretty stable, but it’s still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!

Read more about other types of Vitamin C:

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

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. 03Caprylic/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.
  4. 04Though 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.
  5. 05In practice, that translates to a long shelf life and a consistently elegant skin feel.
  6. 06While 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.
  7. 07Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
  8. 08This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  9. 09This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures…
  10. 10Carbomer 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.
  11. 11Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  12. 12It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  13. 13Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  14. 14A 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.
  15. 15Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
  16. 16You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.
  17. 17The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.
  18. 18Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.
  19. 19Ceramide EOP is formally known as Ceramide 1.
  20. 20It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side