What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Homosalate 5%
Skin ConditioningEthylhexyl Salicylate 5%
UV AbsorberZinc Oxide 9.3%
Cosmetic ColorantWater
Skin ConditioningCyclopentasiloxane
EmollientPolyhydroxystearic Acid
EmulsifyingDimethicone
EmollientCoconut Alkanes
EmollientStearic Acid
CleansingLecithin
EmollientAloe Barbadensis Leaf Juice
Skin ConditioningIsohexadecane
EmollientIsododecane
EmollientMagnesium Sulfate
Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone
Skin ConditioningTriethoxysilylethyl Polydimethylsiloxyethyl Hexyl Dimethicone
Skin ConditioningPolysilicone-11
Coco-Caprylate/Caprate
EmollientDimethicone/PEG-10/15 Crosspolymer
Dipropylene Glycol
HumectantSodium Citrate
BufferingTocopherol
AntioxidantCetearyl Olivate
Sorbitan Olivate
EmulsifyingSodium Hyaluronate
HumectantPhenoxyethanol
PreservativeHydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
Emulsion StabilisingSqualane
EmollientPolysorbate 60
EmulsifyingSorbitan Isostearate
EmulsifyingCaprylyl Glycol
EmollientEthylhexylglycerin
Skin ConditioningHexylene Glycol
EmulsifyingPhosphatidylcholine
EmulsifyingMannitol
HumectantGlycerin
HumectantMethylpropanediol
SolventCaprylic/Capric Triglyceride
MaskingEctoin
Skin ConditioningPalmitic Acid
EmollientHaematococcus Pluvialis Extract
AntioxidantTetrahexyldecyl Ascorbate
AntioxidantPanthenol
Skin ConditioningPhenylpropanol
MaskingVanilla Planifolia Fruit Extract
Skin ConditioningSilica
AbrasiveDimethicone/Vinyl Dimethicone Crosspolymer
Skin ConditioningAcetyl Zingerone
AntioxidantCamellia Sinensis Leaf Extract
AntimicrobialSodium Benzoate
MaskingPotassium Sorbate
PreservativeOctyldodecanol
EmollientSorbitan Oleate
EmulsifyingCI 77491
Cosmetic ColorantCI 77492
Cosmetic ColorantHomosalate 5%, Ethylhexyl Salicylate 5%, Zinc Oxide 9.3%, Water, Cyclopentasiloxane, Polyhydroxystearic Acid, Dimethicone, Coconut Alkanes, Stearic Acid, Lecithin, Aloe Barbadensis Leaf Juice, Isohexadecane, Isododecane, Magnesium Sulfate, Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone, Triethoxysilylethyl Polydimethylsiloxyethyl Hexyl Dimethicone, Polysilicone-11, Coco-Caprylate/Caprate, Dimethicone/PEG-10/15 Crosspolymer, Dipropylene Glycol, Sodium Citrate, Tocopherol, Cetearyl Olivate, Sorbitan Olivate, Sodium Hyaluronate, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Squalane, Polysorbate 60, Sorbitan Isostearate, Caprylyl Glycol, Ethylhexylglycerin, Hexylene Glycol, Phosphatidylcholine, Mannitol, Glycerin, Methylpropanediol, Caprylic/Capric Triglyceride, Ectoin, Palmitic Acid, Haematococcus Pluvialis Extract, Tetrahexyldecyl Ascorbate, Panthenol, Phenylpropanol, Vanilla Planifolia Fruit Extract, Silica, Dimethicone/Vinyl Dimethicone Crosspolymer, Acetyl Zingerone, Camellia Sinensis Leaf Extract, Sodium Benzoate, Potassium Sorbate, Octyldodecanol, Sorbitan Oleate, CI 77491, CI 77492
Ethylhexyl Methoxycinnamate 5.5%
UV AbsorberEthylhexyl Salicylate 3.5%
UV AbsorberTitanium Dioxide 4%
Cosmetic ColorantZinc Oxide 3%
Cosmetic ColorantWater
Skin ConditioningCyclopentasiloxane
EmollientHydrogenated Starch Hydrolysate
HumectantCaprylic/Capric Triglyceride
MaskingCetearyl Olivate
Butylene Glycol
HumectantGlycerin
HumectantSorbitan Olivate
EmulsifyingDimethicone
EmollientAloe Barbadensis Leaf Juice
Skin ConditioningIsodecyl Neopentanoate
EmollientDiisopropyl Sebacate
EmollientSorbitan Stearate
EmulsifyingTetrahexyldecyl Ascorbate
AntioxidantGlyceryl Stearate
EmollientTocopherol
AntioxidantAllantoin
Skin ConditioningLauryl Lactate
EmollientSqualane
EmollientYeast Extract
Skin ConditioningPlankton Extract
Skin ConditioningBetula Alba Bark Extract
MaskingCamellia Sinensis Leaf Extract
AntimicrobialPalmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine
Skin ConditioningSilica
AbrasiveLecithin
EmollientCetyl Alcohol
EmollientPEG-100 Stearate
SurfactantHydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
Emulsion StabilisingPolysorbate 60
EmulsifyingPalmitoyl Tripeptide-5
Skin ConditioningEpigallocatechin Gallate
AntioxidantUbiquinone
AntioxidantSimmondsia Chinensis Meal Extract
EmollientGlyceryl Isostearate
EmollientTetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate
Skin ConditioningTocopheryl Acetate
AntioxidantPolyhydroxystearic Acid
EmulsifyingBoron Nitride
AbsorbentPhenoxyethanol
PreservativeChlorphenesin
AntimicrobialHydroxyethylcellulose
Emulsion StabilisingXanthan Gum
EmulsifyingMagnesium Chloride
Triethoxycaprylylsilane
Sorbic Acid
PreservativeBenzoic Acid
MaskingIron Oxides
CI 77491
Cosmetic ColorantCI 77492
Cosmetic ColorantCI 77499
Cosmetic ColorantEthylhexyl Methoxycinnamate 5.5%, Ethylhexyl Salicylate 3.5%, Titanium Dioxide 4%, Zinc Oxide 3%, Water, Cyclopentasiloxane, Hydrogenated Starch Hydrolysate, Caprylic/Capric Triglyceride, Cetearyl Olivate, Butylene Glycol, Glycerin, Sorbitan Olivate, Dimethicone, Aloe Barbadensis Leaf Juice, Isodecyl Neopentanoate, Diisopropyl Sebacate, Sorbitan Stearate, Tetrahexyldecyl Ascorbate, Glyceryl Stearate, Tocopherol, Allantoin, Lauryl Lactate, Squalane, Yeast Extract, Plankton Extract, Betula Alba Bark Extract, Camellia Sinensis Leaf Extract, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Silica, Lecithin, Cetyl Alcohol, PEG-100 Stearate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Polysorbate 60, Palmitoyl Tripeptide-5, Epigallocatechin Gallate, Ubiquinone, Simmondsia Chinensis Meal Extract, Glyceryl Isostearate, Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate, Tocopheryl Acetate, Polyhydroxystearic Acid, Boron Nitride, Phenoxyethanol, Chlorphenesin, Hydroxyethylcellulose, Xanthan Gum, Magnesium Chloride, Triethoxycaprylylsilane, Sorbic Acid, Benzoic Acid, Iron Oxides, CI 77491, CI 77492, CI 77499
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Aloe Barbadensis Leaf Juice comes from leaves of the aloe plant. Aloe Barbadensis Leaf Juice is best known for helping to soothe sunburns. It is also anti-inflammatory, moisturizing, antiseptic, and can help heal wounds.
Aloe is packed with good stuff including Vitamins A, C, and E. These vitamins are antioxidants, which help fight free-radicals and the damage they may cause. Free-radicals are molecules that may damage your skin cells, such as pollution.
Aloe Barbadensis Leaf Juice also contains sugars. These sugars come in the form of monosaccharides and polysaccharides, folic acid, and choline. These sugars are able to help bind moisture to skin.
It also contains minerals such as calcium, 12 anthraquinones, fatty acids, amino acids, and Vitamin B12.
Learn more about Aloe Barbadensis Leaf JuiceCamellia Sinensis Leaf Extract (tea extract) is one of the most well-researched plant extracts in skincare with an impressive resume.
Black tea, green tea, and oolong tea are all harvested from the Camellia Sinensis plant.
Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.
In lab-grown skin models, this translated to younger, healthier, and stronger skin.
There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.
Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.
A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.
The quality of the extract matters a lot here:
Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.
Human Repeated Insult Patch Testing showed no irritation or sensitization at use concentrations (0.86% in leave-on products and up to 30% as leaf water).
Learn more about Camellia Sinensis Leaf ExtractCaprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.
Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that 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. Just 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 ingredientâs final chemical composition and not its marketing name or source.
This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.
Learn more about Caprylic/Capric TriglycerideCetearyl Olivate is a plant-derived emulsifier and texture enhancer. It helps keep the oil and water phases from separating so your formulas stay stable.
You'll likely see it combined with Sorbitan Olivate (together sold as the trade name Olivem 1000). This combination generates a liquid crystal structure that closely resemble the lipid organization of the stratum corneum.
These "skin-like" liquid crystals improve skin barrier integrity and promote the delivery of actives into the skin.
This ingredient is well-tolerated and has no significant sensitization data.
Because it is derived from the fatty acids in olive oil, this ingredient may not be fungal acne safe.
Learn more about Cetearyl OlivateCi 77491 is also hydrated iron III oxide. It's sole purpose is to give a red/pink hue to products.
Iron III oxides are classified as inorganic chemicals for coloring.
Synthetically created Ci 77491 is considered safer than those naturally found. This is because the synthetically created version may contain less impurities. Iron oxides are generally non-toxic and non-allergenic.
Learn more about CI 77491CI 77492 is also hydrated iron III oxide. It's sole purpose is to give a yellow hue to products.
Iron III oxides are classified as inorganic chemicals for coloring.
Synthetically created CI 77492 is considered safer than those naturally found. This is because the synthetically created version may contain less impurities. Iron oxides are generally non-toxic and non-allergenic.
Learn more about CI 77492Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.
Since D5 is volatile, it does its thing and then evaporates off the skin quickly.
The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics
There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.
Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.
The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.
Learn more about CyclopentasiloxaneDimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
What it does:
Dimethicone comes in different viscosities:
Depending on the viscosity, dimethicone has different properties.
Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.
Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.
Learn more about DimethiconeEthylhexyl 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.
Learn more about Ethylhexyl SalicylateGlycerin (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 GlycerinThis 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.
Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.
Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:
It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.
Learn more about LecithinPhenoxyethanol 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 AcidPolysorbate 60 is used to help stabilize products. It is a surfactant and emulsifier. These properties help keep ingredients together in a product. Surfactants help reduce surface tension between ingredients with different states, such as liquids and solids. Emulsifiers help prevent oils and waters from separating.
Polysorbate 60 is sorbitol-based and created from the ethoxylation of sorbitan. Ethoxylation is a chemical reaction used to add ethylene oxide. Sorbitan is a the dehydrated version of sorbitol, a sugar found in fruits.
In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.
Polysorbates are commonly used in medicine and foods.
Learn more about Polysorbate 60Silica, 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.
Learn more about SilicaSorbitan Olivate is created from the fatty acids in olive oil and sorbitol.
This ingredient is an oil in water emulsifier. It helps stabilize a product by preventing oils and waters from separating. Sorbitan Olivate also helps hydrate the skin.
This ingredient is also known as part of Olivem 1000, with Cetearyl Olivate being the other part.
According to a manufacturer, this ingredient helps preserve the natural microbiome of skin. Having a healthy microbiome helps keep our skin healthy and protects against harmful bacteria.
Please note, having a healthy microbiome is different from fungal acne; a healthy microbiome includes small amounts of yeast that normally live on your skin without causing problems.
Fungal acne happens when one type of yeast (Malassezia) grows out of control. This is usually because it's feeding on certain oils or fatty acids. Due to the olive oil base, this ingredient may not be fungal acne safe.
Learn more about Sorbitan OlivateSqualane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).
It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.
This is due to how structurally similar it is to what your skin already produces.
Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.
Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.
No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).
Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.
This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.
Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.
Read more about squalene with an "e".
Though squalane is often called an oil, itâs technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.
The term âoil-freeâ isnât regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.
Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.
A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.
The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.
Learn more about SqualaneTetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.
THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).
Because itâs oil-soluble, THD dives deep into your skinâs fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.
Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when itâs stressed from pollution or sun.
Want to fade dark spots or tackle hyperpigmentation? Youâll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.
A note on THD: Itâs has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).
While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.
THD is pretty stable, but itâs still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!
Read more about other types of Vitamin C:
Learn more about Tetrahexyldecyl AscorbateTocopherol 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.
Learn more about TocopherolWater. 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 WaterZinc 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