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Skin science article

Cetaphil Sheer Mineral Face Liquid Sunscreen Broad Spectrum SPF 50 Versus Paula's Choice Resist Super-Light Wrinkle Defense SPF 30

Cetaphil Sheer Mineral Face Liquid Sunscreen Broad Spectrum SPF 50 Versus Paula's Choice Resist Super-Light Wrinkle Defense SPF 30 This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. This mineral sunscreen covers the full UV range

Cetaphil Sheer Mineral Face Liquid Sunscreen Broad Spectrum SPF 50 Versus Paula's Choice Resist Super-Light Wrinkle Defense SPF 30

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

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

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

Zinc Oxide 12%

Allantoin

Bisabolol

Butyloctyl Salicylate

C12-15 Alkyl Benzoate

Caprylyl Glycol

Caprylyl Methicone

Dimethicone

Dimethiconol

Ethylhexylglycerin

Hexylene Glycol

Isododecane

Lauryl PEG-10 Tris(Trimethylsiloxy)Silylethyl Dimethicone

Lauryl PEG-8 Dimethicone

Niacinamide

Octyldodecyl Neopentanoate

PEG-10

Phenoxyethanol

Polymethylsilsesquioxane

Propanediol

Sodium Chloride

Sodium Hydroxide

Tetrasodium Glutamate Diacetate

Tocopherol

Trilaureth-4 Phosphate

Water

Zinc Oxide 12%, Allantoin, Bisabolol, Butyloctyl Salicylate, C12-15 Alkyl Benzoate, Caprylyl Glycol, Caprylyl Methicone, Dimethicone, Dimethiconol, Ethylhexylglycerin, Hexylene Glycol, Isododecane, Lauryl PEG-10 Tris(Trimethylsiloxy)Silylethyl Dimethicone, Lauryl PEG-8 Dimethicone, Niacinamide, Octyldodecyl Neopentanoate, PEG-10, Phenoxyethanol, Polymethylsilsesquioxane, Propanediol, Sodium Chloride, Sodium Hydroxide, Tetrasodium Glutamate Diacetate, Tocopherol, Trilaureth-4 Phosphate, Water

Cyclopentasiloxane

Zinc Oxide

PEG-12 Dimethicone

PEG/PPG-18/18 Dimethicone

Lauroyl Lysine

Trihydroxystearin

Dimethicone Crosspolymer

Resveratrol

Quercetin

Epigallocatechin Gallate

Tocopheryl Acetate

Tetrahexyldecyl Ascorbate

Adenosine

Salix Nigra Bark Extract

Punica Granatum Extract

Haematococcus Pluvialis Extract

Hydrolyzed Corn Starch

Polysorbate 80

Hydrated Silica

Triethoxycaprylylsilane

Isopropyl Titanium Triisostearate

Iron Oxides

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

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.

Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.

It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation.

A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.

In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.

You'll likely see use concentrations quite low, usually 0.1-0.2%.

Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.

C12-15 Alkyl Benzoate is a lightweight emollient made by combinig benzoic acid with fatty alcohols that are 12-15 carbons long.

In cosmetics, it plays several roles:

The Cosmetic Review Expert Panel has concluded the alkyl benzoate group to be safe as used in cosmetics; it wasn't found to be a skin irritant and unlikely to be absorbed due to its low water solubility.

This report recorded almost 1000 reported uses with concentrations up to 59% in leave-on products but your cosmetics will typically use 0.5-15% depending on the product.

It's often called a "SPF booster": this is because it keeps UV filters properly dissolved and evenly distributed to support a sunscreen's performance. It doesn't actually raise SPF on its own.

Overall, this ingredient is well tolerated.

This ingredient is fungal acne safe because it is an ester of benzoic acid.

Think of this ingredient as two parts stuck together: an oily part and an acid part. Malassezia only gets a meal when it can snip off a fatty acid to eat. With C12-15 Alkyl Benzoate, the acid part is benzoic acid, which isn't a fatty acid and which the yeast can't use as food.

Benzoic acid is actually used as a preservative to stop yeast from growing.

The oily part is a blend of C12-15 fatty alcohols but fatty alcohols in this size range can support only a little Malassezia growth (mostly for one species of Malassezia as well).

In the ingredient, those alcohols stay locked inside the molecule. The yeast can only reach them by snipping the benzoate bond, and that type of bond is harder for it to cut than a normal fatty bond.

So not much gets released. And whatever does get snipped comes packaged with benzoic acid, which discourages yeast growth.

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).

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.

Hexylene Glycol is a multitasker ingredient that works as a solvent, humectant, emulsifier, viscosity reducer, and preservative booster.

It is able to dissolve both water and oil-soluble ingredients to stabilize tricky actives and make products spread more easily.

As a humectant, it pulls water into the skin. But it's a pretty minor moisturizing ingredient compared to other humectants, like glycerin.

Interestingly, it can act as a mild penetration enhancer. One in vitro study on human skin found a 12% concentration upped the absorption of mometasone furoate (a medicinal ingredient used to treat inflammatory skin conditions) up to 7%.

This ingredient is typically used at levels of 0.1-10% depending on the role it's playing.

A patch test study on eczema patients didn't find a significant increase in irritation versus the control group, but the potential for irritation rises at higher concentrations.

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.

Chances are, you eat sodium chloride every day. Sodium Chloride is also known as table salt. This ingredient has many purposes in skincare: thickener, emulsifier, and exfoliator.

You'll most likely find this ingredient in cleansers where it is used to create a gel-like texture. As an emulsifier, it also prevents ingredients from separating.

You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.

You might see this ingredient used in scrubs as a primary exfoliating ingredient.

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. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It 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.
  6. 06A 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.
  7. 07Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  8. 08It 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.
  9. 09On 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.
  10. 10Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  11. 11You'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.
  12. 12Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  13. 13Safety-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.
  14. 14Adverse 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.
  15. 15Sodium 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.
  16. 16In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
  17. 17Your 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.
  18. 18"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
  19. 19Water. 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.
  20. 20So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice Power Berry Serum

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Product

Paula's Choice Perfect Cleansing Oil

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03

Comparison edit

Read side by side