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Paula's Choice Extra Care Non-Greasy Sunscreen SPF 50 Versus COSRX Aloe Soothing Sun Cream SPF 50 PA+++

Paula's Choice Extra Care Non-Greasy Sunscreen SPF 50 Versus COSRX Aloe Soothing Sun Cream SPF 50 PA+++ This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Ho

Paula's Choice Extra Care Non-Greasy Sunscreen SPF 50 Versus COSRX Aloe Soothing Sun Cream SPF 50 PA+++

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Homosalate 10%

Benzophenone-3 6%

Ethylhexyl Salicylate 5%

Butyl Methoxydibenzoylmethane 3%

Octocrylene 2%

Water

Butylene Glycol

PEG-8

Polyethylene

Silica

Dimethicone

Picrasma Excelsa Wood Extract

Sodium Ascorbyl Phosphate

Retinyl Palmitate

Tocopherol

Tocopheryl Acetate

Titanium Dioxide

Aloe Barbadensis Leaf Juice

Bentonite

Methyl Glucose Sesquistearate

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Polyacrylate

Kaolin

Ethylhexylglycerin

Disodium EDTA

Sodium Hydroxide

Phenoxyethanol

Chlorphenesin

Homosalate 10%, Benzophenone-3 6%, Ethylhexyl Salicylate 5%, Butyl Methoxydibenzoylmethane 3%, Octocrylene 2%, Water, Butylene Glycol, PEG-8, Polyethylene, Silica, Dimethicone, Picrasma Excelsa Wood Extract, Sodium Ascorbyl Phosphate, Retinyl Palmitate, Tocopherol, Tocopheryl Acetate, Titanium Dioxide, Aloe Barbadensis Leaf Juice, Bentonite, Methyl Glucose Sesquistearate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Polyacrylate, Kaolin, Ethylhexylglycerin, Disodium EDTA, Sodium Hydroxide, Phenoxyethanol, Chlorphenesin

Ethylhexyl Methoxycinnamate

Glycerin

Propylene Glycol

Cyclopentasiloxane

Phenylbenzimidazole Sulfonic Acid

Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine

Dicaprylyl Carbonate

Isoamyl P-Methoxycinnamate

Potassium Cetyl Phosphate

Alcohol

Glyceryl Stearate

C14-22 Alcohols

Polymethyl Methacrylate

Cetearyl Alcohol

PEG-100 Stearate

Triethanolamine

Dimethicone/Vinyl Dimethicone Crosspolymer

C12-20 Alkyl Glucoside

Aluminum Hydroxide

Stearic Acid

Parfum

Caprylyl Glycol

Aloe Arborescens Leaf Extract

Dipotassium Glycyrrhizate

Carbomer

Xanthan Gum

Limonene

Hexyl Cinnamal

Linalool

Benzyl Salicylate

Geraniol

Benzyl Alcohol

Citronellol

Benzyl Benzoate

Citral

Water, Ethylhexyl Methoxycinnamate, Glycerin, Propylene Glycol, Cyclopentasiloxane, Phenylbenzimidazole Sulfonic Acid, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Dicaprylyl Carbonate, Isoamyl P-Methoxycinnamate, Potassium Cetyl Phosphate, Alcohol, Dimethicone, Butylene Glycol, Glyceryl Stearate, Titanium Dioxide, C14-22 Alcohols, Polymethyl Methacrylate, Cetearyl Alcohol, PEG-100 Stearate, Triethanolamine, Silica, Sodium Hydroxide, Dimethicone/Vinyl Dimethicone Crosspolymer, C12-20 Alkyl Glucoside, Aluminum Hydroxide, Stearic Acid, Parfum, Caprylyl Glycol, Phenoxyethanol, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Aloe Arborescens Leaf Extract, Dipotassium Glycyrrhizate, Carbomer, Xanthan Gum, Limonene, Tocopheryl Acetate, Disodium EDTA, Hexyl Cinnamal, Linalool, Benzyl Salicylate, Geraniol, Benzyl Alcohol, Citronellol, Benzyl Benzoate, Citral

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.

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

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%.

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.

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.

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.

Titanium Dioxide (TD) is a mineral UV filter widely used in sunscreens and cosmetics.

It's one of only two UV filters officially classified as "mineral" by regulatory agencies (the other being Zinc Oxide).

A really common myth is that mineral filters work by reflecting UV light off your skin like tiny mirrors.

They don't only do that; modern research shows TD protects mostly by absorbing UV radiation, the same way chemical filters do.

When researchers measured this, reflection accounted for only about 4-5% of the protection (and less than SPF 2 on its own). The other ~95% comes from absorption: the UV photons hit the particle and their energy gets soaked up by its semiconductor band gap rather than bouncing off.

So "reflects vs. absorbs" was never really the right way to split mineral from chemical filters.

TD gives broad-spectrum protection that's strongest in the UVB and UVA-2 range and weaker in the UVA-1 range. Its UVA protection isn't quite as strong as Zinc Oxide's which is why you'll often see the two paired together.

Together, they make a solid broad-spectrum system.

TD is a great pick for sensitive, acne-prone, or redness-prone skin because it's non-irritating and chemically inert. Regulatory reviews classify it as a non-sensitizer and mild-to-non-irritant.

It's also unlikely to cause the "eye sting" some chemical filters are known for.

The main trade-off is cosmetic; TD can leave a white cast and has a thicker texture. This is why mineral sunscreens are often less cosmetically elegant than chemical or hybrid formulas (and harder to shade-match on deeper skin tones).

Formulators often use micronized or nano-sized TD to cut down on white case and improve spreadability. Smaller particles scatter less visible light so the formula looks less chalky while still filtering UV.

TD is almost always bundled with coatings like Alumina, Silica, Stearic Acid, or Dimethicone. These coatings do two important jobs:

TD can be used at up to 25% in a finished sunscreen; this is the regulatory ceiling in both the US and the EU.

In practice, the amount in any given product varies a lot depending on the target SPF and whether it's paired with other UV filters.

TD is one of the most heavily vetted sunscreen ingredients out there. It is approved as a UV filter in all major markets worldwide, including the US, EU, UK, Japan, Korea, China, Australia, and Canada.

The safety evidence is solid. There was an old worry that nano particles might absorb through skin into the body but multiple studies (including on damaged, sunburned, and UV-irradiated skin) have shown that TD stays on the surface and the layer of dead skin cells on top of everything else.

There's also no evidence of carcinogenicity, mutagenicity, or reproductive toxicity from dermal exposure of this ingredient.

For those who have seen the headline about a 2022 EU ban on TD, that was on TD as a food additive (a complete separate use from topical sunscreen).

There are ongoing questions about how nano-TD might affect marine ecosystems. As of now, there has been no conclusive evidence that any form of TD (or any other sunscreen filter) harms coral reefs or marine life.

The science is still developing and it's a space worth watching rather than packing over.

However, several destinations have reef-safety sunscreen rules that restrict certain chemical filters and steer visitors toward mineral, non-nano options. If you're traveling somewhere with these rules, a non-nano mineral sunscreen is the safe bet.

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. 03Dipropylene Glycol is a synthetically created humectant, stabilizer, and solvent.
  4. 04This ingredient helps:
  5. 05Dipropylene glycol is technically an alcohol, but it belongs to the glycol family (often considered part of the ‘good’ alcohols). This means it is hydrating and gentle on skin unlike drying solvent alcohols like denatured alcohol.
  6. 06As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.
  7. 07Studies show Dipropylene Glycol is considered safe to use in skincare.
  8. 08Ferulic Acid is a plant based antioxidant that can be naturally found in the cell walls of grains like rice, oats, and corn. It has antioxidant and antimicrobial properties, and has the ability to boost the performance of other antioxidants as well.
  9. 09A well-known study found that adding Ferulic Acid to a solution of Vitamins C and E doubled the photoprotection of skin. This is why you'll often see it paired with Vitamin C or Vitamin E serums rather than sold on its own.
  10. 10A 2025 review of 18 human studies found that using Ferulic Acid (0.5-1%) daily for one to three months showed improvements in:
  11. 11As far as allergies go, Ferulic acid is generally well-tolerated but can cause an allergic reaction in very rare cases. It's also worth noting that Ferulic acid is often extracted from plant sources like rice bran or wheat bran, so be sure to path t…
  12. 12Outside of skincare, researchers are also looking into Ferulic Acid for its potential benefits in areas like diabetes, Alzheimer's, and heart health.
  13. 13Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  14. 14Topically, glycerin does several things at once:
  15. 15Your 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.
  16. 16Aquaporin-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.
  17. 17This 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.
  18. 18Just know very high concentrations (>40%) can feel tacky in low humidity.
  19. 19Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  20. 20Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
Source · skinsort.com
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Comparison edit

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