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First Aid Beauty Hydrating Sunscreen Milk SPF 45 Versus Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50

First Aid Beauty Hydrating Sunscreen Milk SPF 45 Versus Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 This chemical sunscreen covers most of the UV range, lighter on the deep UVA that drives aging. This hybrid sunscreen covers the full UV

First Aid Beauty Hydrating Sunscreen Milk SPF 45 Versus Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50

This chemical sunscreen covers most of the UV range, lighter on the deep UVA that drives aging.

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%

Homosalate 7%

Ethylhexyl Salicylate 5%

Octocrylene 9%

Water

Glycerin

Butyloctyl Salicylate

C12-15 Alkyl Benzoate

Pongamia Glabra Seed Oil

Undecane

Betaine

Silica

Colloidal Oatmeal

Glycine Soja Seed Extract

Tridecane

Ethyl Ferulate

Glycine Soja Oil

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Polyglyceryl-4 Laurate

Hydroxyacetophenone

Arachidyl Alcohol

Polyglyceryl-6 Laurate

1,2-Hexanediol

Caprylyl Glycol

Pongamia Pinnata Seed Extract

Behenyl Alcohol

Cellulose Gum

Polyglyceryl-3 Diisostearate

Arachidyl Glucoside

Aloe Barbadensis Leaf Juice

Sodium Phytate

Tocopherol

Oryza Sativa Germ Extract

Oryza Sativa Extract

Sodium Dilauramidoglutamide Lysine

Dunaliella Salina Extract

Haematococcus Pluvialis Extract

Citric Acid

Inulin

Xanthan Gum

Cellulose

Fructose

Glucose

Butyl Methoxydibenzoylmethane 3%, Homosalate 7%, Ethylhexyl Salicylate 5%, Octocrylene 9%, Water, Glycerin, Butyloctyl Salicylate, C12-15 Alkyl Benzoate, Pongamia Glabra Seed Oil, Undecane, Betaine, Silica, Colloidal Oatmeal, Glycine Soja Seed Extract, Tridecane, Ethyl Ferulate, Glycine Soja Oil, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Polyglyceryl-4 Laurate, Hydroxyacetophenone, Arachidyl Alcohol, Polyglyceryl-6 Laurate, 1,2-Hexanediol, Caprylyl Glycol, Pongamia Pinnata Seed Extract, Behenyl Alcohol, Cellulose Gum, Polyglyceryl-3 Diisostearate, Arachidyl Glucoside, Aloe Barbadensis Leaf Juice, Sodium Phytate, Tocopherol, Oryza Sativa Germ Extract, Oryza Sativa Extract, Sodium Dilauramidoglutamide Lysine, Dunaliella Salina Extract, Haematococcus Pluvialis Extract, Citric Acid, Inulin, Xanthan Gum, Cellulose, Fructose, Glucose

Butyl Methoxydibenzoylmethane 2%

Ethylhexyl Methoxycinnamate 7.5%

Octocrylene 2%

Dimethicone

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

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

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.

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.

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).

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. 03Disodium Cocoamphodiacetate is a surfactant and helps cleanse skin. It is created from the fatty acids of coconut oil.
  4. 04Surfactants help rinse oil, dirt, and other pollutants easily from skin. It has a faint fruit-like scent.
  5. 05Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  6. 06Topically, glycerin does several things at once:
  7. 07Your 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.
  8. 08Aquaporin-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.
  9. 09This 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.
  10. 10Just know very high concentrations (>40%) can feel tacky in low humidity.
  11. 11Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  12. 12Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  13. 13It 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.
  14. 14On 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.
  15. 15Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  16. 16You'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.
  17. 17Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  18. 18Safety-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.
  19. 19Adverse 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.
  20. 20Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.
Source · skinsort.com
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Comparison edit

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