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Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus PCA Skin Daily Defense Broad Spectrum SPF 50+

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus PCA Skin Daily Defense Broad Spectrum SPF 50+ This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. What's inside Key Ingredients Benefits Concerns Ingredients

Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus PCA Skin Daily Defense Broad Spectrum SPF 50+

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 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

Ethylhexyl Salicylate 4.9%

Octocrylene

Zinc Oxide

Ectoin

Bisabolol

Butylene Glycol

Butyloctyl Salicylate

Caffeine

Caprylyl Methicone

Citrus Aurantium Dulcis Peel Extract

Cyclopentasiloxane

Ethyl Ferulate

Ethylhexylglycerin

Octyldodecyl Neopentanoate

Oleth-3 Phosphate

PEG-7 Trimethylolpropane Coconut Ether

Polyisobutene

Propanediol

Silybum Marianum Seed Extract

Sodium Hyaluronate

Sodium Stearoyl Glutamate

Tocopheryl Acetate

Triethoxycaprylylsilane

Ethylhexyl Salicylate 4.9%, Octocrylene, Zinc Oxide, Ectoin, Avena Sativa Bran Extract, Bisabolol, Butylene Glycol, Butyloctyl Salicylate, Caffeine, Caprylyl Methicone, Citrus Aurantium Dulcis Peel Extract, Cyclopentasiloxane, Ethyl Ferulate, Ethylhexylglycerin, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Octyldodecyl Neopentanoate, Oleth-3 Phosphate, PEG-7 Trimethylolpropane Coconut Ether, Phenoxyethanol, Polyisobutene, Propanediol, Silybum Marianum Seed Extract, Sodium Hyaluronate, Sodium Stearoyl Glutamate, Tocopheryl Acetate, Triethoxycaprylylsilane, Water

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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.

Avena Sativa Bran Extract comes from oatmeal. The bran is the shell covering the oat.

This ingredient is an abrasive, meaning it exfoliates the top layer of your skin.

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.

This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.

It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.

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.

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!

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 Super Hydrate Overnight MaskIngredients explained

  1. 01Good 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.
  2. 02It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  3. 03Expand to read more
  4. 04Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  5. 05One 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.
  6. 06Butylene 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.
  7. 07BG’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…
  8. 08It’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.
  9. 09Probably 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.
  10. 10As 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…
  11. 11As 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…
  12. 12This long-named, polymer molecule (big molecule from repeated subunits) is a helper ingredient that's good at emulsifying and stabilizing oils into water-based formulas. It also acts as a thickening and gelling agent that creates nice, non-sticky an…
  13. 13The extract of red seaweed that has nice film-forming, skin smoothing and moisturizing properties.​
  14. 14The manufacturer claims that thanks to biomimetic properties between skin proteins and carrageenans it has a very long-lasting action and can form a "second skin". It also gives a "slow-release" effect to oil-loving active ingredients and measurably…
  15. 15We don't have description for this ingredient yet.
  16. 16A natural moisturizer that’s also in our skin
  17. 17A super common, safe, effective and cheap molecule used for more than 50 years
  18. 18Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  19. 19Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  20. 20High-glycerin moisturizers are awesome for treating severely dry skin
Source · incidecoder.com
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Product index

Related product references

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Comparison edit

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