What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Skin ConditioningEthylhexyl Methoxycinnamate
UV AbsorberOctocrylene
UV AbsorberPolymethylsilsesquioxane
C12-15 Alkyl Benzoate
AntimicrobialCaprylic/Capric Triglyceride
MaskingCoco-Caprylate/Caprate
EmollientGlycerin
HumectantBis-Ethylhexyloxyphenol Methoxyphenyl Triazine
Skin ConditioningDiethylamino Hydroxybenzoyl Hexyl Benzoate
UV FilterCetearyl Alcohol
EmollientPotassium Cetyl Phosphate
EmulsifyingIsononyl Isononanoate
EmollientTitanium Dioxide
Cosmetic ColorantZinc Oxide
Cosmetic ColorantGlyceryl Stearate
EmollientPEG-100 Stearate
Butylene Glycol
HumectantScenedesmus Rubescens Extract
Skin ConditioningPhenoxyethanol
PreservativeSaccharide Isomerate
HumectantButyrospermum Parkii Butter
Skin ConditioningSodium Hyaluronate Crosspolymer
HumectantSodium Hyaluronate
HumectantSodium Acetylated Hyaluronate
HumectantHydrolyzed Sodium Hyaluronate
Skin ConditioningSodium Acrylates Copolymer
Lecithin
EmollientXanthan Gum
EmulsifyingTocopheryl Acetate
AntioxidantAloe Barbadensis Leaf Juice
Skin ConditioningVaccinium Myrtillus Fruit Extract
Skin ConditioningHamamelis Virginiana Extract
AntiseborrhoeicCentella Asiatica Extract
CleansingEthylhexylglycerin
Skin ConditioningPropylene Glycol
HumectantChlorphenesin
AntimicrobialPentylene Glycol
Skin ConditioningPolyhydroxystearic Acid
EmulsifyingCitric Acid
BufferingSodium Citrate
BufferingWater, Ethylhexyl Methoxycinnamate, Octocrylene, Polymethylsilsesquioxane, C12-15 Alkyl Benzoate, Caprylic/Capric Triglyceride, Coco-Caprylate/Caprate, Glycerin, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Cetearyl Alcohol, Potassium Cetyl Phosphate, Isononyl Isononanoate, Titanium Dioxide, Zinc Oxide, Glyceryl Stearate, PEG-100 Stearate, Butylene Glycol, Scenedesmus Rubescens Extract, Phenoxyethanol, Saccharide Isomerate, Butyrospermum Parkii Butter, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydrolyzed Sodium Hyaluronate, Sodium Acrylates Copolymer, Lecithin, Xanthan Gum, Tocopheryl Acetate, Aloe Barbadensis Leaf Juice, Vaccinium Myrtillus Fruit Extract, Hamamelis Virginiana Extract, Centella Asiatica Extract, Ethylhexylglycerin, Propylene Glycol, Chlorphenesin, Pentylene Glycol, Polyhydroxystearic Acid, Citric Acid, Sodium Citrate
Water
Skin ConditioningEthylhexyl Methoxycinnamate
UV AbsorberDiethylamino Hydroxybenzoyl Hexyl Benzoate
UV FilterBis-Ethylhexyloxyphenol Methoxyphenyl Triazine
Skin ConditioningOctocrylene
UV AbsorberCaprylic/Capric Triglyceride
MaskingGlycerin
HumectantC12-15 Alkyl Benzoate
AntimicrobialCyclopentasiloxane
EmollientDimethiconol
EmollientScenedesmus Rubescens Extract
Skin ConditioningGlyceryl Stearate
EmollientCeteareth-20
CleansingCeteareth-12
EmulsifyingCetearyl Alcohol
EmollientCetyl Palmitate
EmollientPEG-100 Stearate
Potassium Cetyl Phosphate
EmulsifyingZinc Oxide
Cosmetic ColorantTitanium Dioxide
Cosmetic ColorantDimethicone
EmollientSodium PCA
HumectantSaccharide Isomerate
HumectantSodium Hyaluronate Crosspolymer
HumectantSodium Hyaluronate
HumectantSodium Acetylated Hyaluronate
HumectantHydrolyzed Sodium Hyaluronate
Skin ConditioningErythritol
HumectantChondrus Crispus
MaskingHydrogenated Starch Hydrolysate
HumectantAscophyllum Nodosum Extract
Skin ConditioningAsparagopsis Armata Extract
Skin ProtectingTocopheryl Acetate
AntioxidantBisabolol
AntioxidantCentella Asiatica Extract
CleansingCamellia Sinensis Leaf Extract
AntimicrobialButyrospermum Parkii Butter
Skin ConditioningPanthenol
Skin ConditioningGlycine Soja Seed Extract
Skin ConditioningXanthan Gum
EmulsifyingDisodium EDTA
Polyhydroxystearic Acid
EmulsifyingPhenoxyethanol
PreservativeEthylhexylglycerin
Skin ConditioningCitric Acid
BufferingParfum
MaskingSodium Citrate
BufferingWater, Ethylhexyl Methoxycinnamate, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Octocrylene, Caprylic/Capric Triglyceride, Glycerin, C12-15 Alkyl Benzoate, Cyclopentasiloxane, Dimethiconol, Scenedesmus Rubescens Extract, Glyceryl Stearate, Ceteareth-20, Ceteareth-12, Cetearyl Alcohol, Cetyl Palmitate, PEG-100 Stearate, Potassium Cetyl Phosphate, Zinc Oxide, Titanium Dioxide, Dimethicone, Sodium PCA, Saccharide Isomerate, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydrolyzed Sodium Hyaluronate, Erythritol, Chondrus Crispus, Hydrogenated Starch Hydrolysate, Ascophyllum Nodosum Extract, Asparagopsis Armata Extract, Tocopheryl Acetate, Bisabolol, Centella Asiatica Extract, Camellia Sinensis Leaf Extract, Butyrospermum Parkii Butter, Panthenol, Glycine Soja Seed Extract, Xanthan Gum, Disodium EDTA, Polyhydroxystearic Acid, Phenoxyethanol, Ethylhexylglycerin, Citric Acid, Parfum, Sodium Citrate
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
You might know this ingredient as Tinosorb S or Bemotrizinol. It is a UV filter that covers both UVA and UVB rays.
This ingredient has two peak UV absorption peaks ( 310 and 340 nm) and is able to absorb both UV-A and UV-B rays. This ingredient works by preventing UV rays from reaching and damaging your skin.
On top of that - it is highly photostable and helps prevent the photodegration of other sunscreen ingredients such as avobenzone.
Tinosorb S is allowed in the EU, Australia, and Asia. It is close to being approved by the FDA and we'll hopefully get this ingredient in the U.S. by late 2026.
Fun fact: Tinosorb S is the most effective UV absorber at maximum concentration (measured by SPF) permitted in the EU.
This ingredient is oil-soluble, so your oil-cleansers will take this right off at night.
Learn more about Bis-Ethylhexyloxyphenol Methoxyphenyl TriazineThis ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.
Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).
In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).
Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
Learn more about Butyrospermum Parkii ButterC12-15 Alkyl Benzoate is made up of Benzoic Acid and long chain alcohols. It has a low molecular weight.
C12-15 Alkyl Benzoate is an emollient and texture enhancer. Due to its solubility, it is often used in sunscreens to help evenly distribute active ingredients.
As an emollient, C12-15 Alkyl Benzoate helps soften and hydrate your skin. Emollients create a film on your skin that traps moisture within.
This ingredient has been reported to cause eye irritation.
Learn more about C12-15 Alkyl BenzoateThis ingredient is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping the skin prevent moisture loss.
It helps thicken a product's formula and makes it easier to spread by dissolving clumping compounds.
Caprylic Triglyceride is made by combining glycerin with coconut oil, forming a clear liquid. Though it behaves like an oil, it is not technically one due to its chemical composition. It is very stable, resistant to oxidation, and unlikely to go rancid. In practice, that translates to a long shelf life and a consistently elegant skin feel.
While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Be sure to patch test if you have concerns.
Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
Learn more about Caprylic/Capric TriglycerideCentella Asiatica Extract (Centella) is derived from an herb native to Southeast Asia. It is famous for its anti-inflammatory and soothing properties.
Centella is rich in antioxidants and amino acids, such as Madecassic Acid and Asiaticoside.
Studies show the compounds in centella help with:
The combination of all these properties makes centella effective at soothing, hydrating, and protecting the skin.
Other great components of centella include Vitamin A, vitamin C, several B vitamins, and Asiatic Acid.
Fun fact: Centella has been used as a medicine and in food for many centuries. As a medicine, it is used to treat burns, scratches, and wounds.
Learn more about Centella Asiatica ExtractCetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
It plays several roles in a formula:
Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.
This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
Learn more about Cetearyl AlcoholCitric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
In skincare formulas, citric acid can:
While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
Read more about some other popular AHA's here:
Learn more about Citric AcidDiethylamino Hydroxybenzoyl Hexyl Benzoate (DHHB) is a chemical UV-A absorber. It is formulated for high UVA protection (320-400 nm).
DHHB is well-liked for:
DHHB has been approved by the EU, Japan, Taiwan, and South America for use up to 10%. Unfortunately, it has not been approved for use in the US or Canada due to slow regulatory processes.
This ingredient is soluble in oils, fats, and lipids.
Learn more about Diethylamino Hydroxybenzoyl Hexyl BenzoateEthylhexyl Methoxycinnamate is an organic compound that provides UVB protection. It often goes by the more common name of octinoxate. It is created from methoxycinnamic acid and 2-ethylhexanol.
Ethylhexyl Methoxycinnamate absorbs UVB rays with wavelengths between 280-320 nm. UV absorbers protect your skin by using chemical reactions to convert UV rays into heat and energy.
UVB (290-320 nm) rays emit more energy than UVA rays. They are capable of damaging DNA, causing sunburns and are thought to be linked to skin cancer.
The state of Hawaii has banned sunscreens containing octinoxate due to its potential impact on coral reefs. More research is needed to bridge gaps in this research. The European Union allows higher levels of octinoxate in sunscreens than the US and Australia.
Ethylhexyl Methoxycinnamate is oil soluble. It is not stable and may lose efficacy when exposed to sunlight.
Learn more about Ethylhexyl MethoxycinnamateEthylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
The 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 to patch test if you are unsure.
Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
Learn more about EthylhexylglycerinGlycerin (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.
Learn more about GlycerinGlyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.
Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.
This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.
A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.
Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.
Fun fact: The human body also creates Glyceryl Stearate naturally.
Learn more about Glyceryl StearateThis ingredient is created by putting sodium hyaluronate through hydrolysis.
You might know this as 'mini' or 'ultra low-molecular weight' hyaluronic acid. The small molecule size means it is able to travel deeper in the skin.
According to studies, low molecular-weight hyaluronic acid can:
One study from 2011 found ultra-low weight HA to show pro-inflammatory properties. Another study from 2022 found it to downregulate UV-B induced inflammation.
Hydrolysis is a process of changing a molecule using water or enzymes.
This ingredient is water-soluble.
Learn more about Hydrolyzed Sodium HyaluronateOctocrylene protects skin from sun damage. It absorbs UV-B with peak absorption of 304 nm. It is a common sunscreen ingredient and often paired with avobenzone, a UVA filter. This is because octocrylene stabilizes other sunscreen ingredients by protecting them from degradation when exposed to sunlight. Octocrylene is a photostable ingredient and loses about 10% of SPF in 95 minutes.
Octocrylene also acts as an emollient, meaning it helps skin retain moisture and softens skin. It is oil-soluble and hydrophobic, enhancing water-resistant properties in a product.
Those who are using ketoprofen, a topical anti-inflammatory drug, may experience an allergic reaction when using octocrylene. It is best to speak with a healthcare professional about using sunscreens with octocrylene.
The EU allows a maximum of these concentrations:
Learn more about OctocrylenePeg-100 Stearate is an emollient and emulsifier. As an emollient, it helps keep skin soft by trapping moisture in. On the other hand, emulsifiers help prevent oil and water from separating in a product.
PEGS are a hydrophilic polyether compound . There are 100 ethylene oxide monomers in Peg-100 Stearate. Peg-100 Stearate is polyethylene glycol ester of stearic acid.
Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.
It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.
Polyhydroxystearic Acid is a vegetable-derived soft wax made from castor oil. It's an emulsion stabilizer, thickener, and film former.
You'll likely see it in sunscreens because it helps disperse pigments and UV-reflecting minerals like titanium dioxide and zinc oxide evenly.
Depending on the concentration, it can drastically change the texture of a product from pasty solid (like lipstick) to sprayable liquid.
The CIR Expert Panel for Cosmetic Ingredient Safety has concluded this ingredient to be safe in cosmetics. The highest reported use concentration is 14.2% in lipsticks.
Learn more about Polyhydroxystearic AcidPotassium Cetyl Phosphate is the potassium salt of a mixture. This mixture consists of the esters from phosphoricacid and cetyl alcohol.
Potassium Cetyl Phosphate is an emulsifier and cleansing agent. Emulsifiers help stabilize a product. It does this by preventing certain ingredients from separating.
As a cleansing agent, Potassium Cetyl Phosphate helps gather oils, dirts, and pollutants from your skin. This makes it easier to rinse them away with water.
Learn more about Potassium Cetyl PhosphateSaccharide Isomerate comes from sugars found in corn. It is a skin hydrator.
The structure of this ingredient can be altered to be more similar to the carbohydrates found in our skin. This ability to mimic our skin gives it hydrating properties.
Specifically, saccharide Isomerate is a humectant. Humectants draw moisture from the air to our skin.
Research shows Saccharide Isomerate to be an effective moisturizer.
Learn more about Saccharide IsomerateWe don't have a description for Scenedesmus Rubescens Extract yet.
Sodium Acetylated Hyaluronate is a type of Hyaluronic Acid.
Hyaluronic Acids help moisturize, soothe, and protect the skin.
Read about common types of Hyaluronic Acid here:
Learn more about Sodium Acetylated HyaluronateSodium Citrate is the sodium salts of citric acid. In skincare, it is used to alter pH levels and acts as a preservative.
Its main functions are to maintain the pH of a product and neutralize metal ions.
The acidity of our skin is maintained by our glands and skin biome; normal pH level of skin is slightly acidic (~4.75-5.5).
Being slightly acidic allows our skin to create an "acid mantle". This acid mantle is a thin barrier that protects our skin from bacteria and contaminants.
Learn more about Sodium CitrateSodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.
In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.
Interestingly, the size of the molecule affects its behavior:
Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.
Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.
You'll typically see concentrations between 0.1-2% for this ingredient.
Learn more about Sodium HyaluronateSodium Hyaluronate Crosspolymer is a crosslinked version of sodium hyaluronate. This just means it's linked into a 3D mesh network that lets it be more stable and sit on skin as a cohesive, gel-like film rather than sinking into skin.
A 2016 human skin study found crosslinked HA increased epidermal water content by 7.6% over the control group and reduced transepidermal water loss by 27.8%.
A follow-up clinical trial found that a topical crosslinked HA serum applied after fillers, microneedling, or chemical peels was well-tolerated and enhanced skin quality at 14 / 28 days.
More recent research suggests that concentrations as low as 0.03% can act as a penetration enhancer for other skincare actives.
Learn more about Sodium Hyaluronate CrosspolymerTitanium dioxide is a mineral UV filter widely used in sunscreens and cosmetics.
It is one of only two UV filters officially classified as “mineral” by regulatory agencies, the other being zinc oxide.
Titanium dioxide provides broad-spectrum protection mostly in the UVB and UVAII range, with some protection in the UVAI range.
While its UVA protection isn’t as strong as zinc oxide’s, the difference is minor.
A common myth is that mineral UV filters reflect UV light. However, modern research shows titanium dioxide absorbs UV radiation like chemical filters (~95% absorption & 5% reflection).
Thanks to its non-irritating nature, titanium dioxide is suitable for sensitive, acne-prone, or redness-prone skin. It is unlikely to cause "eye sting" like other sunscreen ingredients.
A major drawback of this ingredient is its white cast and thick texture. This is why mineral sunscreens often leave a white cast and are less cosmetically elegant than chemical/hybrid sunscreens.
To improve white cast and spreadability, micronized or nano-sized titanium dioxide is often used.
There are ongoing concerns surrounding nano-titanium oxide's impact on marine ecosystems.
There is no conclusive evidence that any form of titanium oxide (or any other sunscreen ingredients) will cause harm to marine ecosystems or coral reefs. The science is still developing but many consumers are keeping a close eye on this issue.
Please note, many destinations have reef-safety sunscreen rules. For instance, the U.S. Virgin Islands advises all visitors to use non-nano mineral sunscreens.
Nano mineral sunscreens once raised safety concerns about absorption into skin.
Extensive research has shown that they do not penetrate healthy or damaged skin; they remain safely on the surface and the top layer of dead skin (stratum corneum).
You'll likely find titanium dioxide bundled with alumina, silica, or dimethicone. These ingredients help make titanium dioxide highly photostable; this prevents it from interacting with other formula components under UV light.
Learn more about Titanium DioxideTocopheryl Acetate is AKA Vitamin E. It is an antioxidant and protects your skin from free radicals. Free radicals damage the skin by breaking down collagen.
One study found using Tocopheryl Acetate with Vitamin C decreased the number of sunburned cells.
Tocopheryl Acetate is commonly found in both skincare and dietary supplements.
Learn more about Tocopheryl AcetateWater. 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!
Learn more about WaterXanthan 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.
Learn more about Xanthan GumZinc Oxide is a mineral broad-spectrum UV filter; it is the broadest UVA and UVB reflector approved by the FDA. It also has skin protectant and skin soothing properties.
Zinc oxide is one of the most effective broad-spectrum UV filters. It protects against UVB, UVAII, and UVAI. In comparison to its counterpart titanium dioxide, zinc oxide provides uniform and extended UVA protection.
Another great benefit? This ingredient is highly photostable so it won't degrade easily under sunlight.
A common myth is that mineral UV filters are widely believed to primarily reflect UV light.
However, modern research shows titanium dioxide absorbs UV radiation like chemical filters (~95% absorption & 5% reflection).
Zinc oxide has great skin soothing properties so you'll likely find this in sunscreens formulated for sensitive skin or babies/children. It is unlikely to cause "eye sting" like other sunscreen ingredients.
Regulatory agencies consider zinc oxide to be non-toxic and safe. It has also been shown to not penetrate the skin.
Unfortunately, this ingredient does leave a visible white cast. This is why mineral sunscreens are often less cosmetically elegant than chemical or hybrid ones.
In cosmetics, zinc oxide can be found in both non-nano and nano-sized forms. The nano version is used to reduce white cast and improve the texture of sunscreen formulas.
There are ongoing concerns surrounding nano-zinc oxide's impact on marine ecosystems and whether it can be absorbed into skin.
Regarding marine ecosystems and coral reefs, there is no conclusive evidence that any form of zinc oxide (or any other sunscreen ingredients) will cause harm. The science is still developing but many consumers are keeping a close eye on this issue.
Please note, many destinations have reef-safety sunscreen rules. For instance, the U.S. Virgin Islands advises all visitors to use non-nano mineral sunscreens.
There has also been some stir about whether micronized or nano zinc oxide has potential photoxicity and absorption through the skin/lungs.
An in-vitro (done in a test tube or petri dish) study demonstrated micronized zinc oxide to have potential phototoxicity. There's no need to fret; the EU Commission's Scientific Committee on Consumer Safety has stated, "The relevance of these findings needs to be clarified by appropriate investigations in vivo." Or in other words, further studies done on living organisms are needed to prove this.
Current research shows zinc oxide nanoparticles do not penetrate intact or sunburned skin. They either remain on the surface or in the outermost layer of dead skin (stratum corneum).
Zinc oxide is one of only two classified mineral UV filters with titanium dioxide being the other one.
Fun fact: Zinc has been used throughout history as an ingredient in paint and medicine. An Indian text from 500BC is believed to list zinc oxide as a salve for open wound. The Ancient Greek physician Dioscorides has also mentioned the use of zinc as an ointment in 1AD.
Learn more about Zinc Oxide