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Skin science article

Paula's Choice Calm Redness Relief SPF 30 Mineral Moisturizer for Normal to Dry Skin Versus Coxir Ceramide Daily UV Sun Block SPF 50+ PA+++

Paula's Choice Calm Redness Relief SPF 30 Mineral Moisturizer for Normal to Dry Skin Versus Coxir Ceramide Daily UV Sun Block SPF 50+ PA+++ This calming moisturizer is formulated around Avena Sativa Kernel Extract and Allantoin to calm redness and hydrate skin

Paula's Choice Calm Redness Relief SPF 30 Mineral Moisturizer for Normal to Dry Skin Versus Coxir Ceramide Daily UV Sun Block SPF 50+ PA+++

This calming moisturizer is formulated around Avena Sativa Kernel Extract and Allantoin to calm redness and hydrate skin.

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

Titanium Dioxide 3.85%

Zinc Oxide 3.12%

Water

C12-15 Alkyl Benzoate

Isononyl Isononanoate

Prunus Armeniaca Kernel Oil

Cyclopentasiloxane

Glyceryl Stearate

PEG-100 Stearate

Butylene Glycol

Pentylene Glycol

Cetearyl Alcohol

Dimethicone

Glycine Soja Sterols

Vp/Eicosene Copolymer

Avena Sativa Kernel Extract

Glycerin

Sodium Hyaluronate

Allantoin

Tocopheryl Acetate

Hydrogenated Lecithin

Tetrahexyldecyl Ascorbate

Superoxide Dismutase

Ubiquinone

Ceramide Ng

Methicone

Palmitoyl Hexapeptide-12

PEG-10 Dimethicone

Cucumis Sativus Fruit Extract

Caprylic/Capric Triglyceride

Tribehenin

PEG-10 Phytosterol

Sorbitan Stearate

Polyhydroxystearic Acid

Alumina

Polysorbate 20

Aluminum Stearate

Xanthan Gum

Caprylyl Glycol

Disodium EDTA

Ethylhexylglycerin

Phenoxyethanol

Chlorphenesin

Titanium Dioxide 3.85%, Zinc Oxide 3.12%, Water, C12-15 Alkyl Benzoate, Isononyl Isononanoate, Prunus Armeniaca Kernel Oil, Cyclopentasiloxane, Glyceryl Stearate, PEG-100 Stearate, Butylene Glycol, Pentylene Glycol, Cetearyl Alcohol, Dimethicone, Glycine Soja Sterols, Vp/Eicosene Copolymer, Avena Sativa Kernel Extract, Glycerin, Sodium Hyaluronate, Allantoin, Tocopheryl Acetate, Hydrogenated Lecithin, Tetrahexyldecyl Ascorbate, Superoxide Dismutase, Ubiquinone, Ceramide Ng, Methicone, Palmitoyl Hexapeptide-12, PEG-10 Dimethicone, Cucumis Sativus Fruit Extract, Caprylic/Capric Triglyceride, Tribehenin, PEG-10 Phytosterol, Sorbitan Stearate, Polyhydroxystearic Acid, Alumina, Polysorbate 20, Aluminum Stearate, Xanthan Gum, Caprylyl Glycol, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol, Chlorphenesin

Titanium Dioxide

Aluminum Hydroxide

Stearic Acid

Cyclomethicone

Isohexadecane

Zinc Oxide

Ethylhexyl Methoxycinnamate

Isoamyl P-Methoxycinnamate

4-Methylbenzylidene Camphor

Cetyl PEG/PPG-10/1 Dimethicone

Disteardimonium Hectorite

Beeswax

Ozokerite

Aloe Barbadensis Leaf Extract

Camellia Sinensis Leaf Extract

Collagen Extract

Myrciaria Dubia Fruit Extract

Malpighia Emarginata Fruit Extract

Magnesium Sulfate

Linoleic Acid

Ceramide NP

Tea-Cocoyl Glutamate

Camellia Japonica Seed Oil

Parfum

Water, Titanium Dioxide, Aluminum Hydroxide, Stearic Acid, Cyclomethicone, PEG-10 Dimethicone, Isohexadecane, Zinc Oxide, Methicone, Ethylhexyl Methoxycinnamate, Isoamyl P-Methoxycinnamate, Cyclopentasiloxane, 4-Methylbenzylidene Camphor, Glycerin, Cetyl PEG/PPG-10/1 Dimethicone, Disteardimonium Hectorite, Isononyl Isononanoate, Beeswax, Ozokerite, Sodium Hyaluronate, Aloe Barbadensis Leaf Extract, Camellia Sinensis Leaf Extract, Collagen Extract, Myrciaria Dubia Fruit Extract, Malpighia Emarginata Fruit Extract, Magnesium Sulfate, Hydrogenated Lecithin, Linoleic Acid, Ceramide NP, Tea-Cocoyl Glutamate, Caprylic/Capric Triglyceride, Camellia Japonica Seed Oil, Phenoxyethanol, Ethylhexylglycerin, Parfum

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.

Since D5 is volatile, it does its thing and then evaporates off the skin quickly.

The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics

There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.

Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.

The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.

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.

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.

Hydrogenated Lecithin is a more stable version of lecithin.

It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

Isononyl Isononanoate is a synthetic skin-conditioner and texture enhancer. It is created from nonanoic acid, a fatty acid found in cocoa and lavender oil.

As an emollient, Isononyl Isononanoate helps keep your skin soft and smooth. This is because emollients create a barrier on the skin to trap moisture in.

Isononyl Isononanoate helps give products a velvet feel and improves spreadability.

Methicone is a type of silicone and is a simpler form of dimethicone.

Silicones are used to enhance the texture of products and have emollient properties. Methicone is used to give products a silky texture and improves spreadability.

Peg-10 Dimethicone is silicone with conditioner and emulsifier properties. It mostly acts as an emollient in skincare and and humectant in haircare.

According to the manufacturer, acidic formulations decrease the stability of this ingredient. It works best in neutral or near neutral formulations.

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.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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!

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

Paula's Choice Resist Anti-Aging Serum Foundation - MatteIngredients explained

  1. 01A clear, colorless and odorless, highly volatile (meaning it does not absorb into the skin but evaporates from it) liquid that's used as an emollient. It gives a nice non-oily light skin feel and it can improve the slip of the formula without leavin…
  2. 02It's also popular in make-up products as its volatility makes mascaras and foundations last longer. If that would not be enough, it's also an excellent solvent, and it's a regular not only on the ingredients lists of make-ups but also on makeup removers.
  3. 03Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
  4. 04It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  5. 05Expand to read more
  6. 06Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  7. 07One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
  8. 08A hydrocarbon-based emollient that can come in different viscosities from silky-light through satiny-smooth to luxurious, rich. It forms a non-occlusive film on the surface of the skin and brings gloss without greasiness to the formula. It's a very …
  9. 09We don't have description for this ingredient yet.
  10. 10An odorless, slightly yellowish powder that's used as a polymer microsphere (a tiny little ball from repeated subunits). It gives products an elegant, silky texture and better slip. It can also scatter light to blur fine lines while letting enough l…
  11. 11Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.
  12. 12BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting…
  13. 13It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.
  14. 14Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.
  15. 15As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's…
  16. 16As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build…
  17. 17A silicone emulsifier that helps water and silicone oils to mix nicely together.
  18. 18A natural emulsifier that brings a soft and powdery feel to the formula. It's also very gentle and is recommended for sensitive or baby skin products.
  19. 19A helper ingredient that is used as a bulking and viscosity controlling agent. It is also an emulsion stabilizer in water-in-oil emulsions, where water droplets are dispersed in the continuous oil phase and not the other way round.
  20. 20It can also be used as a heat generating agent in water-less formulas as it has an instant heat-generating chemical reaction with water.
Source · incidecoder.com
02

Product index

Related product references

Product

Paula's Choice The Unscrub

Paula's Choice The Unscrub Paula's Choice The Unscrub ingredients explained: Aqua (Water), Jojoba Esters (Cleansing Beads), Caprylic/Capric Triglyceride (Skin-Replenishing), Glycerin (Skin …

Source: incidecoder.comView reference →
03

Comparison edit

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