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Skin science article

Paula's Choice Resist Super-Light Wrinkle Defense SPF 30 Versus Glow Recipe Watermelon Glow Niacinamide Sunscreen SPF 50

Paula's Choice Resist Super-Light Wrinkle Defense SPF 30 Versus Glow Recipe Watermelon Glow Niacinamide Sunscreen SPF 50 This mineral sunscreen covers the full UV range and blocks ~97% of UVB at SPF 30. This hybrid sunscreen covers the full UV range and blocks

Paula's Choice Resist Super-Light Wrinkle Defense SPF 30 Versus Glow Recipe Watermelon Glow Niacinamide Sunscreen SPF 50

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

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

Water

Cyclopentasiloxane

Zinc Oxide

PEG-12 Dimethicone

PEG/PPG-18/18 Dimethicone

Lauroyl Lysine

Sodium Chloride

Trihydroxystearin

Dimethicone Crosspolymer

Resveratrol

Quercetin

Epigallocatechin Gallate

Tocopheryl Acetate

Tetrahexyldecyl Ascorbate

Adenosine

Bisabolol

Salix Nigra Bark Extract

Punica Granatum Extract

Haematococcus Pluvialis Extract

Hydrolyzed Corn Starch

Polysorbate 80

Hydrated Silica

Triethoxycaprylylsilane

C12-15 Alkyl Benzoate

Isopropyl Titanium Triisostearate

Caprylyl Glycol

Hexylene Glycol

Ethylhexylglycerin

Iron Oxides

Phenoxyethanol

Water, Cyclopentasiloxane, Zinc Oxide, PEG-12 Dimethicone, PEG/PPG-18/18 Dimethicone, Lauroyl Lysine, Sodium Chloride, Trihydroxystearin, Dimethicone Crosspolymer, Resveratrol, Quercetin, Epigallocatechin Gallate, Tocopheryl Acetate, Tetrahexyldecyl Ascorbate, Adenosine, Bisabolol, Salix Nigra Bark Extract, Punica Granatum Extract, Haematococcus Pluvialis Extract, Hydrolyzed Corn Starch, Polysorbate 80, Hydrated Silica, Triethoxycaprylylsilane, C12-15 Alkyl Benzoate, Isopropyl Titanium Triisostearate, Caprylyl Glycol, Hexylene Glycol, Ethylhexylglycerin, Iron Oxides, Phenoxyethanol

Homosalate 8.5%

Ethylhexyl Salicylate 5%

Octocrylene 8.5%

Zinc Oxide 12.1%

Caprylic/Capric Triglyceride

Propanediol

Glycerin

Cetearyl Olivate

Polyhydroxystearic Acid

Ethylhexyl Methoxycrylene

Potassium Cetyl Phosphate

Phenyl Trimethicone

Dimethicone

Sorbitan Olivate

Inulin Lauryl Carbamate

Xanthan Gum

1,2-Hexanediol

Hydroxyacetophenone

Polyester-8

Diethylhexyl Syringylidenemalonate

Cetearyl Alcohol

Menthone Glycerin Acetal

Lactic Acid

Arachidyl Alcohol

Chlorphenesin

Citrullus Lanatus Fruit Extract

Niacinamide

Sodium Stearoyl Glutamate

Coco-Glucoside

Behenyl Alcohol

Trisodium Ethylenediamine Disuccinate

Aloe Barbadensis Leaf Juice

Silica

Arachidyl Glucoside

Sodium Citrate

Parfum

Sodium Hyaluronate

Magnesium Aspartate

Zinc Gluconate

Copper Gluconate

Homosalate 8.5%, Ethylhexyl Salicylate 5%, Octocrylene 8.5%, Zinc Oxide 12.1%, Water, Caprylic/Capric Triglyceride, Propanediol, Glycerin, Cetearyl Olivate, Polyhydroxystearic Acid, Ethylhexyl Methoxycrylene, Potassium Cetyl Phosphate, Lauroyl Lysine, Phenyl Trimethicone, Dimethicone, Sorbitan Olivate, Inulin Lauryl Carbamate, Xanthan Gum, Triethoxycaprylylsilane, 1,2-Hexanediol, Caprylyl Glycol, Hydroxyacetophenone, Polyester-8, Diethylhexyl Syringylidenemalonate, Cetearyl Alcohol, Menthone Glycerin Acetal, Lactic Acid, Arachidyl Alcohol, Chlorphenesin, Citrullus Lanatus Fruit Extract, Niacinamide, Sodium Stearoyl Glutamate, Coco-Glucoside, Behenyl Alcohol, Trisodium Ethylenediamine Disuccinate, Aloe Barbadensis Leaf Juice, Silica, Dimethicone Crosspolymer, Arachidyl Glucoside, Sodium Citrate, Parfum, Sodium Hyaluronate, Magnesium Aspartate, Zinc Gluconate, Phenoxyethanol, Copper Gluconate

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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Dimethicone Crosspolymer is a silicone created by modifying dimethicone with hydrocarbon side chains. Due to its large size, it does not penetrate skin. It is considered non-occlusive.

Dimethicone Crosspolymer is used to stabilize and thicken products. It also helps give products a silky feel.

This ingredient comes from a fatty acid (lauric acid) and amino acid (lysine). It is used to add a silky feel to cosmetics.

According to a manufacturer, its fatty acid base leaves a silky feeling on the skin. It also has emollient properties because of this. Emollients help soften skin by preventing water from evaporating.

Lauroyl lysine is barely soluble in water.

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.

Triethoxycaprylylsilane is a silicon-based surface modifier that makes sunscreens feel silky and makeup stay put.

Its main job is to coat mineral particles like titanium dioxide, zinc oxide, and color pigments in a thin, oily layer so they spread smoothly, don't clump, and stick to skin better.

This ingredient is typically used at low levels (up to 2.5% in eyeshadow and 1% in lipstick).

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!

Zinc Oxide (ZO) is a mineral broad-spectrum UV filter and the broadest-spectrum filter recognized by the FDA. It covers everything from UVB through to long-wave UVA.

On top of sun protection, it has skin protectant and skin-soothing properties too.

Here's a myth worth busting: mineral filters are usually described as working by "reflecting" or "bouncing" UV off your skin.

That's mostly not true: when researchers actually measured it, ZO and Titanium Dioxide reflect only about 4-5% of UV (less than SPF 2 worth of protection).

The vast majority of the work (~95%) is done by absorption, similar to chemical UV filters. ZO is a semiconductor that absorbs UV photos through its energy band gap.

So the old "physical blocker vs. chemical absorber" framing is really an oversimplification.

Zinc Oxide is one of the most effective broad-spectrum UV filters out there. It protects across UVB, UVA2, and UVA1 with a flat, even absorption curve across the whole UVA-UVB range.

That uniform UVA coverage is its standout feature; titanium dioxide skews more toward UVB as its particle size drops so ZO gives more consistent and extended UVA protection.

It's also very photostable. As an inorganic oxide, ZO doesn't break down in sunlight the way some organic filters can, so it holds up over a day of wear.

This ingredient is gentle and soothing, making it go-to for sunscreens aimed at sensitive skin, rosacea, or ecezma-prone skin, babies, and children.

It's also unlikely to cause the "eye sting" that some sunscreen ingredients are known for, and regulatory agencies broadly consider it non-toxic and safe for topical use.

Beyond sun protection, ZO is also a recognized OTC skin protectant. It forms a breathable barrier that shields skin from moisture and irritation while supporting healing. This is why you'll see it as a classic active in diaper rash creams.

The only downside to ZO is that it can leave a visible white cast, especially on deeper skin tones. This is the main reason mineral sunscreens have historically felt less cosmetically elegant than chemical or hybrid formulas.

Zinc Oxide comes in both non-nano and nano forms. The dividing line is 100nm and anything under is classified as a nanomaterial by the EU.

The nano version scatters less visible light which cuts down white case and gives a lighter, more wearable texture.

Another thing worth understanding about formulation:

Uncoated ZO has some inherent photocatalytic activity. This just means it can generate reactive oxygen species under UV. It's exactly why cosmetic-grade ZO is almost always surface-coated; this coating suppresses that reactivity and improves how the powder disperses and feels.

A well-formulated coated ZO largely sidesteps this issue.

Zinc Oxide is commonly used anywhere from 10% up to the regulatory maximum in sunscreens (25%).

Mineral-only broad-spectrum products often land in the 15-25% range to hit higher SPF and UVA values. Keep in mind SPF performance depends heavily on particle size, dispersion, and the rest of the formula, and not just the percentage.

As an OTC skin protectant like diaper creams, ZO typically runs higher at roughly 10-40%.

This ingredient is generally easy to work with and doesn't photodegrade.

The only thing to know is that uncoated ZO can be a bit reactive in a formula.

Under UV, it can break down sensitive ingredients like other actives or UV filters. This is another reason coated versions are standard. ZO can also react with very acidic ingredients or throw off stability of some creams. A good formula will get around this with the right coatings and dispersion.

The EU's Scientific Committee on Consumer Safety has concluded that ZO nanoparticles "can be considered to not pose any risk of adverse effects in humans after application on healthy, intact or sunburnt skin".

You might hear that ZO is "toxic"; this is because an in-vitro (test tube) study suggested micronized ZO had potential phototoxicity. In vivo (human) investigations have disputed this and the results have come back reassuring.

So does ZO penetrate skin? The short answer is no, not in any way that matters.

The most relevant evidence comes from real-world human studies: in one, volunteers applied ZO nanoparticle sunscreen hourly for six hours and daily for five days. The advanced imaging showed the particles stayed on the surface and never reached the living epidermis, and no cellular toxicity was found.

Other in-vivo and ex-vivo work agree; ZO nanoparticles don't cross the stratum corneum, even on flexed, massaged, or barrier-impaired skin.

A small amount of solubilized zinc ions can dissolve off the particles and enter the upper skin. But the quantities are tiny compared to the zinc already naturally present in your body, and studies haven't found this to cause local toxicity.

The sunscreen bans you've heard of (like Hawaii's) are aimed at two chemical filters, Oxybenzone and Octinoxate. ZO itself it not banned and is often recommended instead.

So far, there's no solid evidence that any form of ZO harms reefs. It is an ongoing and active area of study, and worth keeping an eye on.

If you're traveling somewhere with these rules, a non-nano mineral sunscreen is the safe bet.

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. 06Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, …
  7. 07Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.
  8. 08Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.
  9. 09Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
  10. 10It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.
  11. 11While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
  12. 12If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.
  13. 13Sodium 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.
  14. 14In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
  15. 15Your 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.
  16. 16"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
  17. 17Water. 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.
  18. 18So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
  19. 19You'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!
  20. 20Xanthan 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.
Source · skinsort.com
02

Product index

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03

Comparison edit

Read side by side