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Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus Bolden SPF 30 BRIGHTENING MOISTURIZER

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus Bolden SPF 30 BRIGHTENING MOISTURIZER This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. This brightening moisturizer is formulated around Tetrahexyldecyl A

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus Bolden SPF 30 BRIGHTENING MOISTURIZER

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

This brightening moisturizer is formulated around Tetrahexyldecyl Ascorbate and Butyrospermum Parkii Butter to brighten dull-looking skin and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Homosalate 15%

Butyl Methoxydibenzoylmethane 3%

Octocrylene 2.7%

Butyrospermum Parkii Butter

Caprylic/Capric Triglyceride

Potassium Cetyl Phosphate

Cetearyl Olivate

Sorbitan Olivate

Tetrahexyldecyl Ascorbate

Trehalose

Squalane

Parfum

Carthamus Tinctorius Oleosomes

Allantoin

Carbomer

Ethylhexylglycerin

Oryza Sativa Bran Extract

Echinacea Purpurea Extract

Helianthus Annuus Extract

Rosmarinus Officinalis Leaf Extract

Acetyl Rheum Rhaponticum Root Extract

Panthenyl Triacetate

Trisodium Ethylenediamine Disuccinate

Sodium Hydroxide

Homosalate 15%, Ethylhexyl Salicylate 5%, Butyl Methoxydibenzoylmethane 3%, Octocrylene 2.7%, Water, Glycerin, Butyrospermum Parkii Butter, Caprylic/Capric Triglyceride, Potassium Cetyl Phosphate, Cetearyl Olivate, Silica, Sorbitan Olivate, Tetrahexyldecyl Ascorbate, Trehalose, Squalane, Parfum, Phenoxyethanol, Carthamus Tinctorius Oleosomes, Tocopherol, Allantoin, Xanthan Gum, Carbomer, Ethylhexylglycerin, Oryza Sativa Bran Extract, Echinacea Purpurea Extract, Helianthus Annuus Extract, Rosmarinus Officinalis Leaf Extract, Acetyl Rheum Rhaponticum Root Extract, Panthenyl Triacetate, Trisodium Ethylenediamine Disuccinate, Sodium Hydroxide

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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.

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.

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.

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.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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. 03Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.
  4. 04It'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.
  5. 05A 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.
  6. 06In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.
  7. 07You'll likely see use concentrations quite low, usually 0.1-0.2%.
  8. 08Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.
  9. 09Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  10. 10Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  11. 11Though 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.
  12. 12Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.
  13. 13This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.
  14. 14This ingredient can also be found in pill medicines to help our bodies digest other ingredients.
  15. 15Salicylic 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, …
  16. 16Unlike 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.
  17. 17Salicylic 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.
  18. 18Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
  19. 19It 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.
  20. 20While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
Source · skinsort.com
02

Product index

Related product references

Product

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Paula's Choice C15 Super Booster Paula's Choice C15 Super Booster ingredients explained: Aqua/Water/Eau⁠, Ascorbic Acid⁠, Glycerin⁠, Ethoxydiglycol⁠, PPG-26-Buteth-26⁠, Mannitol⁠, Tridecape…

Source: incidecoder.comView reference →
03

Comparison edit

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