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Skin science article

Paula's Choice 5% Vitamin C Sheer Moisturizer SPF 50 Versus Ultra Violette Clean Screen SPF 30 Fragrance Free Weightless Gel Skinscreen

Paula's Choice 5% Vitamin C Sheer Moisturizer SPF 50 Versus Ultra Violette Clean Screen SPF 30 Fragrance Free Weightless Gel Skinscreen This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. This hybrid sunscreen covers the full UV ra

Paula's Choice 5% Vitamin C Sheer Moisturizer SPF 50 Versus Ultra Violette Clean Screen SPF 30 Fragrance Free Weightless Gel Skinscreen

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

This hybrid sunscreen covers the full UV range and blocks ~97% of UVB at SPF 30.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Butyl Methoxydibenzoylmethane

Ethylhexyl Methoxycinnamate

Ethylhexyl Salicylate

Octocrylene

Water

Glycerin

Silica

3-O-Ethyl Ascorbic Acid

Ascorbyl Glucoside

Dimethicone

Propanediol

Tetrahexyldecyl Ascorbate

Acetyl Zingerone

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Diethylhexyl Syringylidenemalonate

Dimethicone/Vinyl Dimethicone Crosspolymer

Porphyra Umbilicalis Extract

Hydrogenated Lecithin

Ricinus Communis Seed Oil

Sodium Hydroxide

Tocopherol

Xanthan Gum

Ethylhexylglycerin

Laureth-4

Phenoxyethanol

Potassium Sorbate

Sodium Benzoate

Titanium Dioxide

Iron Oxides

Entada Phaseoloides Bark/Seed Extract

Butyl Methoxydibenzoylmethane, Ethylhexyl Methoxycinnamate, Ethylhexyl Salicylate, Octocrylene, Water, Glycerin, Silica, 3-O-Ethyl Ascorbic Acid, Ascorbyl Glucoside, Dimethicone, Propanediol, Tetrahexyldecyl Ascorbate, Acetyl Zingerone, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Diethylhexyl Syringylidenemalonate, Dimethicone/Vinyl Dimethicone Crosspolymer, Porphyra Umbilicalis Extract, Hydrogenated Lecithin, Ricinus Communis Seed Oil, Sodium Hydroxide, Tocopherol, Xanthan Gum, Ethylhexylglycerin, Laureth-4, Phenoxyethanol, Potassium Sorbate, Sodium Benzoate, Titanium Dioxide, Iron Oxides, Entada Phaseoloides Bark/Seed Extract

Titanium Dioxide 3%

Methylene Bis-Benzotriazolyl Tetramethylbutylphenol 2.25%

Diethylamino Hydroxybenzoyl Hexyl Benzoate 1.6%

Butylene Glycol

Caprylic/Capric Triglyceride

Caprylyl Glycol

Polysorbate 60

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Saccharide Isomerate

Decyl Glucoside

Caprylhydroxamic Acid

Propylene Glycol

Citric Acid

Sodium Chloride

CI 77491

CI 77492

CI 77499

Titanium Dioxide 3%, Methylene Bis-Benzotriazolyl Tetramethylbutylphenol 2.25%, Diethylamino Hydroxybenzoyl Hexyl Benzoate 1.6%, Water, Butylene Glycol, Caprylic/Capric Triglyceride, Silica, Caprylyl Glycol, Polysorbate 60, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Saccharide Isomerate, Decyl Glucoside, Caprylhydroxamic Acid, Glycerin, Propylene Glycol, Xanthan Gum, Citric Acid, Dimethicone, Sodium Chloride, CI 77491, CI 77492, CI 77499

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.

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.

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.

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.

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.

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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Palmitoyl Tripeptide-1 (aka Pal-GHK) is a synthetic signal peptide made of three amino acids attached to palmitic acid.
  14. 14That fatty acid attachment is the key: it boosts the peptide's ability to penetrate the skin barrier. This puts it closer to the dermal cells where it can actually make a difference.
  15. 15Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.
  16. 16In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than…
  17. 17Human clinical data is promising, but modest:
  18. 18A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.
  19. 19A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.
  20. 20You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

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