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Skin science article

Cetaphil Pro Oil Absorbing Moisturizer With Spf 30 Broad Spectrum Versus Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50

Cetaphil Pro Oil Absorbing Moisturizer With Spf 30 Broad Spectrum Versus Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 This oil-control moisturizer is formulated around Polymethyl Methacrylate and Aluminum Starch Octenylsuccinate to balanc

Cetaphil Pro Oil Absorbing Moisturizer With Spf 30 Broad Spectrum Versus Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50

This oil-control moisturizer is formulated around Polymethyl Methacrylate and Aluminum Starch Octenylsuccinate to 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

Butyl Methoxydibenzoylmethane 3%

Ethylhexyl Salicylate 5%

Octocrylene 7%

Water

Isopropyl Lauroyl Sarcosinate

Glycerin

Dimethicone

Diisopropyl Sebacate

Silica

Polymethyl Methacrylate

Aluminum Starch Octenylsuccinate

Sucrose Tristearate

Dimethiconol

Pentylene Glycol

Polysorbate 61

Sodium Stearoyl Glutamate

Phenoxyethanol

Caprylyl Glycol

Tocopheryl Acetate

Glycyrrhetinic Acid

Panthenol

Triethanolamine

Allantoin

Carbomer

Potassium Sorbate

Zinc Gluconate

Xanthan Gum

Disodium EDTA

Hydroxypalmitoyl Sphinganine

Butyl Methoxydibenzoylmethane 3%, Ethylhexyl Salicylate 5%, Octocrylene 7%, Water, Isopropyl Lauroyl Sarcosinate, Glycerin, Dimethicone, Diisopropyl Sebacate, Silica, Polymethyl Methacrylate, Aluminum Starch Octenylsuccinate, Sucrose Tristearate, Dimethiconol, Pentylene Glycol, Polysorbate 61, Sodium Stearoyl Glutamate, Phenoxyethanol, Caprylyl Glycol, Tocopheryl Acetate, Glycyrrhetinic Acid, Panthenol, Triethanolamine, Allantoin, Carbomer, Potassium Sorbate, Zinc Gluconate, Xanthan Gum, Disodium EDTA, Hydroxypalmitoyl Sphinganine

Butyl Methoxydibenzoylmethane 2%

Ethylhexyl Methoxycinnamate 7.5%

Octocrylene 2%

Tocopherol

Chamomilla Recutita Flower Extract

Vitis Vinifera Seed Extract

Camellia Sinensis Leaf Extract

Camellia Oleifera Leaf Extract

Peucedanum Graveolens Extract

Sambucus Nigra Fruit Extract

Avena Sativa Bran Extract

Punica Granatum Extract

Lycium Barbarum Fruit Extract

Hydrogenated Lecithin

Titanium Dioxide

Dimethicone/Vinyl Dimethicone Crosspolymer

Diethylhexyl Syringylidenemalonate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Sodium Carbomer

Benzyl Alcohol

Sodium Benzoate

Butyl Methoxydibenzoylmethane 2%, Ethylhexyl Methoxycinnamate 7.5%, Ethylhexyl Salicylate 5%, Octocrylene 2%, Water, Glycerin, Silica, Dimethicone, Tocopherol, Chamomilla Recutita Flower Extract, Vitis Vinifera Seed Extract, Camellia Sinensis Leaf Extract, Camellia Oleifera Leaf Extract, Peucedanum Graveolens Extract, Sambucus Nigra Fruit Extract, Avena Sativa Bran Extract, Punica Granatum Extract, Lycium Barbarum Fruit Extract, Hydrogenated Lecithin, Titanium Dioxide, Dimethicone/Vinyl Dimethicone Crosspolymer, Diethylhexyl Syringylidenemalonate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Xanthan Gum, Sodium Carbomer, Benzyl Alcohol, Sodium Benzoate, Potassium Sorbate, 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.

Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).

It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.

This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.

Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.

The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.

It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.

Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.

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.

Ethylhexyl Salicylate (also called Octisalate or Octyl Salicylate) is an oil-soluble organic UV filter that's been used in sunscreen since the 1950's.

It absorbs UVB light in the 280-320 nm range with a peak absorbance around 306 nm.

You'll often see it paired with other UV filters to boost overall SPF because octisalate is a fairly week filter on its own.

The reason you'll see it so often is because it can help solubilize and stabilize the trickier filters like oxybenzone and avobenzone.

Unlike these filters, octisalate has pretty good photostability and doesn't create skin-damaging free radicals when exposed to sunlight.

The fatty-alcohol part of the molecule also gives it a light, emollient feel so it doubles as a nice texture enhancer.

Usage levels vary around the world:

Safety-wise, this ingredient has a pretty reassuring track record. The EU's Scientific Committee on Consumer Products (SCCP) found very low skin penetration in human skin tests and negative results for irritation, phototoxicity, and photoallergy.

The real-world allergy risk is pretty low too; a 2012 European study of 1,031 people recorded only 2 reactions to it (a rate of 0.19%).

You might have seen scary headlines about sunscreen getting into your blood.

In 2019, the FDA found that several chemical filters can absorb through the skin and show up in the bloodstream at small but measurable levels.

Here's the important part: these tiny levels are just a cutoff the FDA uses to decide which ingredients need more testing and doesn't mean anything harmful was found.

The researchers were clear that the results are no reason to stop wearing sunscreen.

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.

Octocrylene is an oil-soluble organic UV filter that mainly absorbs UVB and short wave UVA II light.

Its real superpower is teamwork: octocrylene is remarkably photostable and is most famous for stabilizing avobenzone (the workhorse UVA filter).

This ingredient is commonly used to enhance both UVB and UVA protection due to its unique property in stabilizing avobenzone. It also pulls double duty by boosting water resistance and giving formulas a smooth, spreadable feel.

The EU's Scientific Committee on Consumer Safety (SCCS) has deemed octocrylene to be safe as a UV-filter at concentrations up to 10% (capped at 9% in propellant sprays). The US also permits it up to 10%.

Two things worth knowing:

You'll usually see this ingredient used in concentrations between 2-10% (higher amounts when used as a stabilizer for avobenzone).

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.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

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.

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. 03Aloe Barbadensis Leaf Juice is the filtered, stabilized liquid pressed from the inner gel of the aloe vera leaf.
  4. 04In cosmetics, it shows up as either soothing active or a water-replacement base. It is roughly 98-99% water and the last 1-2% is an interesting mix of polysaccharides, amino acids, vitamins, minerals, and enzymes.
  5. 05The polysaccharides do most of the work: they bind water at the skin surface for a light, non-greasy hydration boost. And one of the polysaccharides, glycomannan, is linked to fibroblast stimulation + collagen synthesis. This is also why aloe has su…
  6. 06This ingredient is also calming with anti-inflammatory and mild antimicrobial activity, making it a great pick for sensitive, irritated, or post-sun skin.
  7. 07Realistic expectations matter though; the solid evidence is mostly limited to hydration, soothing, and wound support. Deeper claims about anti-aging or sun protection are not well backed, and science reviews note it does not prevent radiation-induce…
  8. 08Because it plays well with almost everything, it's commonly used as a base alongside other actives like niacinamide or vitamin C.
  9. 09Typical usage concentrations range from 0.5% (where hydration benefits already show up) all the way to 90%+ (where it replaces water as the main base).
  10. 10The safety for this ingredient is well-establish as well. Overall, this is a great supporting ingredient for those who want a boost in hydration.
  11. 11Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  12. 12The 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 …
  13. 13Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  14. 14Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  15. 15It 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.
  16. 16On 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.
  17. 17Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  18. 18You'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.
  19. 19Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  20. 20Safety-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.
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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