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Medik8 Daily Radiance Vitamin C Versus Paula's Choice Resist Skin Restoring Moisturizer With SPF 50

Medik8 Daily Radiance Vitamin C Versus Paula's Choice Resist Skin Restoring Moisturizer With SPF 50 This brightening day moisturizer is formulated around Tetrahexyldecyl Ascorbate and Tocopheryl Acetate to brighten dull-looking skin and soften the look of wrin

Medik8 Daily Radiance Vitamin C Versus Paula's Choice Resist Skin Restoring Moisturizer With SPF 50

This brightening day moisturizer is formulated around Tetrahexyldecyl Ascorbate and Tocopheryl Acetate to brighten dull-looking skin and soften the look of wrinkles.

This barrier-repair moisturizer is formulated around Allantoin and Niacinamide to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Tetrahexyldecyl Ascorbate

Diethylamino Hydroxybenzoyl Hexyl Benzoate

Dibutyl Adipate

Dimethicone

Ethylhexyl Triazone

Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine

C12-15 Alkyl Benzoate

Dicaprylyl Carbonate

Cetearyl Alcohol

Glycerin

Coco-Glucoside

Phenoxyethanol

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Cetearyl Glucoside

Tocopheryl Acetate

Hydroxyacetophenone

Disodium EDTA

Benzoic Acid

Xanthan Gum

Citrus Grandis Peel Oil

Sodium Hydroxide

Dehydroacetic Acid

Sodium Hyaluronate

Citrus Limon Peel Oil

Citrus Aurantium Bergamia Fruit Oil

Pelargonium Graveolens Flower Oil

Ethylhexylglycerin

Limonene

Citronellol

Linalool

Geraniol

Citral

Water, Tetrahexyldecyl Ascorbate, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Dibutyl Adipate, Dimethicone, Ethylhexyl Triazone, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, C12-15 Alkyl Benzoate, Dicaprylyl Carbonate, Cetearyl Alcohol, Glycerin, Coco-Glucoside, Phenoxyethanol, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Cetearyl Glucoside, Tocopheryl Acetate, Hydroxyacetophenone, Disodium EDTA, Benzoic Acid, Xanthan Gum, Citrus Grandis Peel Oil, Sodium Hydroxide, Dehydroacetic Acid, Sodium Hyaluronate, Citrus Limon Peel Oil, Citrus Aurantium Bergamia Fruit Oil, Pelargonium Graveolens Flower Oil, Ethylhexylglycerin, Limonene, Citronellol, Linalool, Geraniol, Citral

Butyl Methoxydibenzoylmethane 3%

Homosalate 5%

Ethylhexyl Methoxycinnamate 7.5%

Ethylhexyl Salicylate 5%

Benzophenone-3

Silica

Butylene Glycol

Pentylene Glycol

Potassium Cetyl Phosphate

Cyclopentasiloxane

Pyrus Malus Fruit Extract

Vp/Eicosene Copolymer

Butyrospermum Parkii Butter

Allantoin

Niacinamide

Tocopherol

Glycyrrhiza Glabra Root Extract

Aloe Barbadensis Leaf Juice

Atractylodes Macrocephala Root Powder

Avena Sativa Kernel Extract

Coffea Arabica Seed Extract

Portulaca Oleracea Extract

Mahonia Aquifolium Root Extract

Diethylhexyl Syringylidenemalonate

Sarcosine

Capryloyl Glycine

Maltooligosyl Glucoside

Dimethiconol

Hydrogenated Starch Hydrolysate

Hexylene Glycol

4-T-Butylcyclohexanol

Glyceryl Stearate

PEG-100 Stearate

Caprylyl Glycol

Butyl Methoxydibenzoylmethane 3%, Homosalate 5%, Ethylhexyl Methoxycinnamate 7.5%, Ethylhexyl Salicylate 5%, Benzophenone-3, Water, Silica, Glycerin, Cetearyl Alcohol, Dimethicone, Butylene Glycol, Pentylene Glycol, Potassium Cetyl Phosphate, Cyclopentasiloxane, Pyrus Malus Fruit Extract, Vp/Eicosene Copolymer, Butyrospermum Parkii Butter, Allantoin, Niacinamide, Tocopherol, Glycyrrhiza Glabra Root Extract, Aloe Barbadensis Leaf Juice, Atractylodes Macrocephala Root Powder, Avena Sativa Kernel Extract, Coffea Arabica Seed Extract, Portulaca Oleracea Extract, Mahonia Aquifolium Root Extract, Diethylhexyl Syringylidenemalonate, Sarcosine, Capryloyl Glycine, Maltooligosyl Glucoside, Cetearyl Glucoside, Dimethiconol, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Hydrogenated Starch Hydrolysate, Hexylene Glycol, 4-T-Butylcyclohexanol, Glyceryl Stearate, PEG-100 Stearate, Sodium Hydroxide, Xanthan Gum, Disodium EDTA, Phenoxyethanol, Caprylyl Glycol, 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.

Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.

As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.

It 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.

A 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.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Cetearyl Glucoside is a sugar-based emulsifier. It is usually made by combining cetearyl alcohol and glucose.

Belonging to the aklyl polyglucoside (APG) family, Cetearyl Glucoside has a sugar "head" that loves water and a fatty "tail" that loves oil. This means it can shuffle oil and water into a stable and smooth emulsion.

Typical use levels are between 1-5% and this ingredient is considered to be non-irritating by the CIR Expert Panel Review.

Once applied, your skin's glucoside hydrolases breaks it down to the parent fatty alcohol and glucose. This is why this ingredient may not be fungal acne safe.

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.

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.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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. 03Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.
  4. 04Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.
  5. 05This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.
  6. 06A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.
  7. 07Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.
  8. 08Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.
  9. 09Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.
  10. 10Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  11. 11Topically, glycerin does several things at once:
  12. 12Your 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.
  13. 13Aquaporin-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.
  14. 14This 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.
  15. 15Just know very high concentrations (>40%) can feel tacky in low humidity.
  16. 16Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  17. 17This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.
  18. 18It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.
  19. 19Sodium 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.
  20. 20In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.
Source · skinsort.com
02

Product index

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03

Comparison edit

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