Skin science article
Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus Isntree Hyaluronic Acid Watery Sun Gel SPF 50+ PA++++
Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus Isntree Hyaluronic Acid Watery Sun Gel SPF 50+ PA++++ This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. This chemical sunscreen covers the full UV range an
Paula's Choice Resist Youth-Extending Daily Hydrating Fluid SPF 50 Versus Isntree Hyaluronic Acid Watery Sun Gel SPF 50+ PA++++
This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.
This chemical 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
Butylene Glycol
Ethylhexyl Salicylate
Homosalate
Dibutyl Adipate
Niacinamide
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine
Cyclopentasiloxane
Methylene Bis-Benzotriazolyl Tetramethylbutylphenol
Polysilicone-15
Diethylamino Hydroxybenzoyl Hexyl Benzoate
1,2-Hexanediol
Pentylene Glycol
Pinus Pinaster Bark Extract
Ceramide NP
Centella Asiatica Extract
Portulaca Oleracea Extract
Houttuynia Cordata Extract
Olea Europaea Fruit Oil
Ficus Carica Fruit Extract
Sodium Hyaluronate
Ceteth-10
Decyl Glucoside
Propanediol
Astaxanthin
Hyaluronic Acid
Sodium Hyaluronate Crosspolymer
Ascorbyl Propyl Hyaluronate
Hydrolyzed Hyaluronic Acid
Hydroxypropyltrimonium Hyaluronate
Acrylates/C10-30 Alkyl Acrylate Crosspolymer
Sodium Acetylated Hyaluronate
Hydrolyzed Sodium Hyaluronate
Adenosine
Cetyl PEG/PPG-10/1 Dimethicone
Tromethamine
Carbomer
Propylene Glycol
Ethylhexylglycerin
Water, Butylene Glycol, Ethylhexyl Salicylate, Homosalate, Dibutyl Adipate, Niacinamide, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Cyclopentasiloxane, Methylene Bis-Benzotriazolyl Tetramethylbutylphenol, Polysilicone-15, Diethylamino Hydroxybenzoyl Hexyl Benzoate, 1,2-Hexanediol, Pentylene Glycol, Pinus Pinaster Bark Extract, Ceramide NP, Centella Asiatica Extract, Glycerin, Portulaca Oleracea Extract, Houttuynia Cordata Extract, Olea Europaea Fruit Oil, Ficus Carica Fruit Extract, Sodium Hyaluronate, Ceteth-10, Hydrogenated Lecithin, Decyl Glucoside, Propanediol, Tocopherol, Astaxanthin, Hyaluronic Acid, Sodium Hyaluronate Crosspolymer, Ascorbyl Propyl Hyaluronate, Hydrolyzed Hyaluronic Acid, Hydroxypropyltrimonium Hyaluronate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Acetylated Hyaluronate, Hydrolyzed Sodium Hyaluronate, Adenosine, Xanthan Gum, Cetyl PEG/PPG-10/1 Dimethicone, Tromethamine, Carbomer, Propylene Glycol, Ethylhexylglycerin
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.
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.
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).
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.