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Paula's Choice Calm Redness Relief SPF 30 Mineral Moisturizer For Normal To Oily Skin Versus SkinCeuticals Physical Fusion UV Defense SPF 50

Paula's Choice Calm Redness Relief SPF 30 Mineral Moisturizer For Normal To Oily Skin Versus SkinCeuticals Physical Fusion UV Defense SPF 50 This calming moisturizer is formulated around Allantoin and Camellia Sinensis Leaf Extract to calm redness and balance

Paula's Choice Calm Redness Relief SPF 30 Mineral Moisturizer For Normal To Oily Skin Versus SkinCeuticals Physical Fusion UV Defense SPF 50

This calming moisturizer is formulated around Allantoin and Camellia Sinensis Leaf Extract to calm redness and balance excess oil.

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

Ethylhexyl Palmitate

Zinc Oxide

Cyclomethicone

Titanium Dioxide

Dimethicone

Glyceryl Stearate

PEG-100 Stearate

C12-15 Alkyl Benzoate

Polysorbate 80

Caprylyl Methicone

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Isohexadecane

Cetyl Alcohol

Propylene Glycol

Polyglyceryl-6 Isostearate

Allantoin

Chamomilla Recutita Flower Extract

Camellia Sinensis Leaf Extract

Glycyrrhiza Glabra Root Extract

Aloe Barbadensis Leaf Juice

Glycerin

Panthenol

Algae Extract

Lauryl PEG-9 Polydimethylsiloxyethyl Dimethicone

Polyhydroxystearic Acid

Triethoxysilylethyl Polydimethylsiloxyethyl Hexyl Dimethicone

Caprylyl Glycol

Butylene Glycol

Diethylhexyl Carbonate

Triethoxycaprylylsilane

Disodium EDTA

Phenoxyethanol

Chlorphenesin

Water, Ethylhexyl Palmitate, Zinc Oxide, Cyclomethicone, Titanium Dioxide, Dimethicone, Glyceryl Stearate, PEG-100 Stearate, C12-15 Alkyl Benzoate, Polysorbate 80, Caprylyl Methicone, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Isohexadecane, Cetyl Alcohol, Propylene Glycol, Polyglyceryl-6 Isostearate, Allantoin, Chamomilla Recutita Flower Extract, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Aloe Barbadensis Leaf Juice, Glycerin, Panthenol, Algae Extract, Lauryl PEG-9 Polydimethylsiloxyethyl Dimethicone, Polyhydroxystearic Acid, Triethoxysilylethyl Polydimethylsiloxyethyl Hexyl Dimethicone, Caprylyl Glycol, Butylene Glycol, Diethylhexyl Carbonate, Triethoxycaprylylsilane, Disodium EDTA, Phenoxyethanol, Chlorphenesin

Isododecane

Undecane

Triethylhexanoin

Nylon-12

Butyloctyl Salicylate

Phenethyl Benzoate

Styrene/Acrylates Copolymer

Silica

Tridecane

Dicaprylyl Carbonate

Dicaprylyl Ether

Talc

Dimethicone/PEG-10/15 Crosspolymer

Aluminum Stearate

Pentylene Glycol

PEG-9 Polydimethylsiloxyethyl Dimethicone

Alumina

Magnesium Sulfate

Iron Oxides

PEG-8 Laurate

Disteardimonium Hectorite

Tocopherol

Propylene Carbonate

Artemia Extract

Benzoic Acid

C9-15 Fluoroalcohol Phosphate

PEG-9

Titanium Dioxide, Zinc Oxide, Water, Dimethicone, Isododecane, C12-15 Alkyl Benzoate, Undecane, Triethylhexanoin, Isohexadecane, Nylon-12, Caprylyl Methicone, Butyloctyl Salicylate, Phenethyl Benzoate, Styrene/Acrylates Copolymer, Silica, Tridecane, Dicaprylyl Carbonate, Dicaprylyl Ether, Talc, Dimethicone/PEG-10/15 Crosspolymer, Aluminum Stearate, Pentylene Glycol, PEG-9 Polydimethylsiloxyethyl Dimethicone, Alumina, Polyhydroxystearic Acid, Phenoxyethanol, Magnesium Sulfate, Caprylyl Glycol, Iron Oxides, PEG-8 Laurate, Disteardimonium Hectorite, Triethoxycaprylylsilane, Tocopherol, Propylene Carbonate, Artemia Extract, Benzoic Acid, C9-15 Fluoroalcohol Phosphate, PEG-9

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.

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).

Caprylyl Methicone is a synthetic and lightweight silicone fluid. It gives products a silky, dry-touch finish without the heaviness of pure oils.

Though the EU CosIng Database lists this ingredient as a skin conditioner, it is also used for sensory reasons. It spreads easily, cuts greasiness, and reduces tackiness.

This ingredient is volatile which means it will mostly evaporate (but it evaporates slower than older cyclomethicones, like Cyclotetrasiloxane).

Typical concentration ranges from 1-30% depending on if it's being used to tweak the feel of a product or acting as the main emollient.

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.

Isohexadecane is added to enhance texture, emulsify, and to help cleanse. It is an isoparrafin. It is a component of petrolatum.

Due to its large size, Isohexadecane is not absorbed by the skin. Instead, it sits on top and acts as an emollient. Emollients help keep your skin soft and smooth by trapping moisture within.

Isohexadecane is often used in products designed to help oily skin. It is lightweight and non-greasy while helping to moisturize. When mixed with silicones, it gives a product a silky feel.

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.

Polyhydroxystearic Acid is a vegetable-derived soft wax made from castor oil. It's an emulsion stabilizer, thickener, and film former.

You'll likely see it in sunscreens because it helps disperse pigments and UV-reflecting minerals like titanium dioxide and zinc oxide evenly.

Depending on the concentration, it can drastically change the texture of a product from pasty solid (like lipstick) to sprayable liquid.

The CIR Expert Panel for Cosmetic Ingredient Safety has concluded this ingredient to be safe in cosmetics. The highest reported use concentration is 14.2% in lipsticks.

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.

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. 03Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.
  4. 04It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.
  5. 05Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.
  6. 06A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.
  7. 07Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.
  8. 08One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.
  9. 09Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.
  10. 10Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  11. 11Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  12. 12It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  13. 13Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  14. 14A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  15. 15Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  16. 16Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  17. 17It plays several roles in a formula:
  18. 18Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  19. 19Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  20. 20However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

Read side by side