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Skin science article

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus La Roche-Posay Toleriane Sensitive UV Face Cream SPF 30 Face Moisturizer

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus La Roche-Posay Toleriane Sensitive UV Face Cream SPF 30 Face Moisturizer This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. This barrier-repair day moisturi

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus La Roche-Posay Toleriane Sensitive UV Face Cream SPF 30 Face Moisturizer

This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.

This barrier-repair day moisturizer is formulated around Niacinamide and Allantoin to strengthen the skin barrier and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Butyl Methoxydibenzoylmethane 2%

Ethylhexyl Methoxycinnamate 7.5%

Ethylhexyl Salicylate 5%

Octocrylene 2%

Water

Glycerin

Silica

Dimethicone

Tocopherol

Chamomilla Recutita Flower Extract

Vitis Vinifera Seed Extract

Camellia Sinensis Leaf Extract

Camellia Oleifera Leaf Extract

Peucedanum Graveolens Extract

Sambucus Nigra Fruit Extract

Avena Sativa Bran Extract

Punica Granatum Extract

Lycium Barbarum Fruit Extract

Hydrogenated Lecithin

Titanium Dioxide

Dimethicone/Vinyl Dimethicone Crosspolymer

Diethylhexyl Syringylidenemalonate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Xanthan Gum

Sodium Carbomer

Benzyl Alcohol

Sodium Benzoate

Potassium Sorbate

Phenoxyethanol

Butyl Methoxydibenzoylmethane 2%, Ethylhexyl Methoxycinnamate 7.5%, Ethylhexyl Salicylate 5%, Octocrylene 2%, Water, Glycerin, Silica, Dimethicone, Tocopherol, Chamomilla Recutita Flower Extract, Vitis Vinifera Seed Extract, Camellia Sinensis Leaf Extract, Camellia Oleifera Leaf Extract, Peucedanum Graveolens Extract, Sambucus Nigra Fruit Extract, Avena Sativa Bran Extract, Punica Granatum Extract, Lycium Barbarum Fruit Extract, Hydrogenated Lecithin, Titanium Dioxide, Dimethicone/Vinyl Dimethicone Crosspolymer, Diethylhexyl Syringylidenemalonate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Xanthan Gum, Sodium Carbomer, Benzyl Alcohol, Sodium Benzoate, Potassium Sorbate, Phenoxyethanol

Octocrylene 7%

Homosalate 5%

Butyl Methoxydibenzoylmethane 3%

Niacinamide

PEG-100 Stearate

Glyceryl Stearate

Ammonium Polyacryloyldimethyl Taurate

Stearic Acid

Sodium Hydroxide

Capryloyl Glycine

Caprylyl Glycol

Citric Acid

Cetyl Alcohol

Palmitic Acid

Disodium EDTA

Allantoin

Ceramide NP

Myristic Acid

Octocrylene 7%, Homosalate 5%, Ethylhexyl Salicylate 5%, Butyl Methoxydibenzoylmethane 3%, Water, Glycerin, Silica, Dimethicone, Niacinamide, PEG-100 Stearate, Glyceryl Stearate, Ammonium Polyacryloyldimethyl Taurate, Stearic Acid, Sodium Hydroxide, Capryloyl Glycine, Caprylyl Glycol, Citric Acid, Cetyl Alcohol, Palmitic Acid, Xanthan Gum, Dimethicone/Vinyl Dimethicone Crosspolymer, Disodium EDTA, Allantoin, Tocopherol, Ceramide NP, Myristic 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.

Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).

It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.

This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.

Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.

The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.

It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.

Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.

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.

This ingredient is a silicone elastomer that works as a texture enhancer, adds a silky slip, and also helps absorb excess oil.

Because it's a large macromolecule that's insoluble in water and chemically inert, it's not expected to penetrate or be absorbed into skin.

Human patch tests with a facial lotion containing 1% of this ingredient found no sensitization.

Ethylhexyl Salicylate (also called Octisalate or Octyl Salicylate) is an oil-soluble organic UV filter that's been used in sunscreen since the 1950's.

It absorbs UVB light in the 280-320 nm range with a peak absorbance around 306 nm.

You'll often see it paired with other UV filters to boost overall SPF because octisalate is a fairly week filter on its own.

The reason you'll see it so often is because it can help solubilize and stabilize the trickier filters like oxybenzone and avobenzone.

Unlike these filters, octisalate has pretty good photostability and doesn't create skin-damaging free radicals when exposed to sunlight.

The fatty-alcohol part of the molecule also gives it a light, emollient feel so it doubles as a nice texture enhancer.

Usage levels vary around the world:

Safety-wise, this ingredient has a pretty reassuring track record. The EU's Scientific Committee on Consumer Products (SCCP) found very low skin penetration in human skin tests and negative results for irritation, phototoxicity, and photoallergy.

The real-world allergy risk is pretty low too; a 2012 European study of 1,031 people recorded only 2 reactions to it (a rate of 0.19%).

You might have seen scary headlines about sunscreen getting into your blood.

In 2019, the FDA found that several chemical filters can absorb through the skin and show up in the bloodstream at small but measurable levels.

Here's the important part: these tiny levels are just a cutoff the FDA uses to decide which ingredients need more testing and doesn't mean anything harmful was found.

The researchers were clear that the results are no reason to stop wearing sunscreen.

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.

Octocrylene is an oil-soluble organic UV filter that mainly absorbs UVB and short wave UVA II light.

Its real superpower is teamwork: octocrylene is remarkably photostable and is most famous for stabilizing avobenzone (the workhorse UVA filter).

This ingredient is commonly used to enhance both UVB and UVA protection due to its unique property in stabilizing avobenzone. It also pulls double duty by boosting water resistance and giving formulas a smooth, spreadable feel.

The EU's Scientific Committee on Consumer Safety (SCCS) has deemed octocrylene to be safe as a UV-filter at concentrations up to 10% (capped at 9% in propellant sprays). The US also permits it up to 10%.

Two things worth knowing:

You'll usually see this ingredient used in concentrations between 2-10% (higher amounts when used as a stabilizer for avobenzone).

Silica, also known as silicon dioxide, is a naturally occurring mineral. It is used as a fine, spherical, and porous powder in cosmetics.

Though it has exfoliant properties, the function of silica varies depending on the product.

The unique structure of silica enhances the spreadability and adds smoothness, making it a great texture enhancer.

It is also used as an active carrier, emulsifier, and mattifier due to its ability to absorb excess oil.

In some products, tiny microneedles called spicules are made from silica or hydrolyzed sponge. When you rub them in, they lightly polish away dead skin layers and enhance the penetration of active ingredients.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

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.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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. 03Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.
  4. 04Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.
  5. 05Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.
  6. 06It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.
  7. 07Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.
  8. 08This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.
  9. 09Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.
  10. 10Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.
  11. 11Arctium Lappa Seed Oil is an oil.
  12. 12Avena Sativa Kernel Extract is is derived from colloidal oatmeal. Besides being a healthy breakfast, oats have many benefits in skincare too.
  13. 13This ingredient helps sooth, hydrate, and protect the skin. The starches in colloidal oatmeal are able to bind water, keeping the skin hydrated.
  14. 14The cellulose and fiber in colloidal oatmeal help reduce inflammation. This can also help the skin feel softer.
  15. 15Colloidal Oatmeal is also an antioxidant. Antioxidants protect our skin from free-radical damage.
  16. 16Oatmeal also contains beneficial compounds:
  17. 17This ingredient is created by mixing grounded oatmeal and a liquid base.
  18. 18Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  19. 19Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  20. 20Though 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.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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