Kate Somerville Hydrakate Illuminating SPF 50+ Drops
A sunscreen with 27 ingredients, including spf, vitamin E, and ectoin.
This mineral sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.
Worth noting
Contains EU-listed fragrance allergens, including Lavandula Angustifolia Oil and Citrus Aurantium Dulcis Peel Oil.
We independently verify ingredients, backed by peer-reviewed research. Suggest an update.
What's inside
Ingredients List
Zinc Oxide 24.5%
Cosmetic ColorantC13-15 Alkane
SolventWater
Skin ConditioningEthyl Macadamiate
Skin ConditioningCaprylic/Capric Triglyceride
MaskingPolyhydroxystearic Acid
EmulsifyingPropanediol
SolventPolyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate
EmulsifyingPolyglyceryl-3 Polyricinoleate
EmulsifyingEctoin
Skin ConditioningHydroxyectoin
BufferingIsostearic Acid
CleansingLecithin
EmollientTrisodium Ethylenediamine Disuccinate
Quaternium-90 Bentonite
Lavandula Angustifolia Oil
MaskingCitrus Aurantium Dulcis Peel Oil
MaskingTriethyl Citrate
MaskingTocopherol
AntioxidantMalic Acid
BufferingStearyl Triethoxysilane
Sodium Chloride
MaskingEthylhexylglycerin
Skin ConditioningPhenoxyethanol
PreservativeCI 77491
Cosmetic ColorantCI 77492
Cosmetic ColorantCI 77499
Cosmetic Colorant
Active Ingredients:
Zinc Oxide 24.5%
Inactive Ingredients:
C13-15 Alkane, Water, Ethyl Macadamiate, Caprylic/Capric Triglyceride, Polyhydroxystearic Acid, Propanediol, Polyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate, Polyglyceryl-3 Polyricinoleate, Ectoin, Hydroxyectoin, Isostearic Acid, Lecithin, Trisodium Ethylenediamine Disuccinate, Quaternium-90 Bentonite, Lavandula Angustifolia Oil, Citrus Aurantium Dulcis Peel Oil, Triethyl Citrate, Tocopherol, Malic Acid, Stearyl Triethoxysilane, Sodium Chloride, Ethylhexylglycerin, Phenoxyethanol, CI 77491, CI 77492, CI 77499
Key Ingredients
Benefits
Concerns
Ingredients Explained
Zinc Oxide (ZO) is a mineral broad-spectrum UV filter and the broadest-spectrum filter recognized by the FDA. It covers everything from UVB through to long-wave UVA.
On top of sun protection, it has skin protectant and skin-soothing properties too.
Here's a myth worth busting: mineral filters are usually described as working by "reflecting" or "bouncing" UV off your skin.
That's mostly not true: when researchers actually measured it, ZO and Titanium Dioxide reflect only about 4-5% of UV (less than SPF 2 worth of protection).
The vast majority of the work (~95%) is done by absorption, similar to chemical UV filters. ZO is a semiconductor that absorbs UV photos through its energy band gap.
So the old "physical blocker vs. chemical absorber" framing is really an oversimplification.
Zinc Oxide is one of the most effective broad-spectrum UV filters out there. It protects across UVB, UVA2, and UVA1 with a flat, even absorption curve across the whole UVA-UVB range.
That uniform UVA coverage is its standout feature; titanium dioxide skews more toward UVB as its particle size drops so ZO gives more consistent and extended UVA protection.
It's also very photostable. As an inorganic oxide, ZO doesn't break down in sunlight the way some organic filters can, so it holds up over a day of wear.
This ingredient is gentle and soothing, making it go-to for sunscreens aimed at sensitive skin, rosacea, or ecezma-prone skin, babies, and children.
It's also unlikely to cause the "eye sting" that some sunscreen ingredients are known for, and regulatory agencies broadly consider it non-toxic and safe for topical use.
Beyond sun protection, ZO is also a recognized OTC skin protectant. It forms a breathable barrier that shields skin from moisture and irritation while supporting healing. This is why you'll see it as a classic active in diaper rash creams.
The only downside to ZO is that it can leave a visible white cast, especially on deeper skin tones. This is the main reason mineral sunscreens have historically felt less cosmetically elegant than chemical or hybrid formulas.
Zinc Oxide comes in both non-nano and nano forms. The dividing line is 100nm and anything under is classified as a nanomaterial by the EU.
The nano version scatters less visible light which cuts down white case and gives a lighter, more wearable texture.
Another thing worth understanding about formulation:
Uncoated ZO has some inherent photocatalytic activity. This just means it can generate reactive oxygen species under UV. It's exactly why cosmetic-grade ZO is almost always surface-coated; this coating suppresses that reactivity and improves how the powder disperses and feels.
A well-formulated coated ZO largely sidesteps this issue.
Zinc Oxide is commonly used anywhere from 10% up to the regulatory maximum in sunscreens (25%).
Mineral-only broad-spectrum products often land in the 15-25% range to hit higher SPF and UVA values. Keep in mind SPF performance depends heavily on particle size, dispersion, and the rest of the formula, and not just the percentage.
As an OTC skin protectant like diaper creams, ZO typically runs higher at roughly 10-40%.
This ingredient is generally easy to work with and doesn't photodegrade.
The only thing to know is that uncoated ZO can be a bit reactive in a formula.
Under UV, it can break down sensitive ingredients like other actives or UV filters. This is another reason coated versions are standard. ZO can also react with very acidic ingredients or throw off stability of some creams. A good formula will get around this with the right coatings and dispersion.
The EU's Scientific Committee on Consumer Safety has concluded that ZO nanoparticles "can be considered to not pose any risk of adverse effects in humans after application on healthy, intact or sunburnt skin".
You might hear that ZO is "toxic"; this is because an in-vitro (test tube) study suggested micronized ZO had potential phototoxicity. In vivo (human) investigations have disputed this and the results have come back reassuring.
So does ZO penetrate skin? The short answer is no, not in any way that matters.
The most relevant evidence comes from real-world human studies: in one, volunteers applied ZO nanoparticle sunscreen hourly for six hours and daily for five days. The advanced imaging showed the particles stayed on the surface and never reached the living epidermis, and no cellular toxicity was found.
Other in-vivo and ex-vivo work agree; ZO nanoparticles don't cross the stratum corneum, even on flexed, massaged, or barrier-impaired skin.
A small amount of solubilized zinc ions can dissolve off the particles and enter the upper skin. But the quantities are tiny compared to the zinc already naturally present in your body, and studies haven't found this to cause local toxicity.
The sunscreen bans you've heard of (like Hawaii's) are aimed at two chemical filters, Oxybenzone and Octinoxate. ZO itself it not banned and is often recommended instead.
So far, there's no solid evidence that any form of ZO harms reefs. It is an ongoing and active area of study, and worth keeping an eye on.
If you're traveling somewhere with these rules, a non-nano mineral sunscreen is the safe bet.
Learn more about Zinc OxideC13-15 Alkane is a group of alkanes with 13 to 15 carbon atoms in the alkyl chain.
It is a solvent and texture enhancer. Solvents are used to keep ingredients together in a product. They can help dissolve ingredients to stable bases or help evenly distribute ingredients throughout the product.
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!
Learn more about WaterEthyl Macadamiate isn't fungal acne safe.
Caprylic/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 ingredient’s 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 TriglyceridePolyhydroxystearic 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 AcidPropanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
It’s often used to:
Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
Learn more about PropanediolThis ingredient is a water-in-oil emulsifier and is sometimes known by its trade name, Isolan GPS. It helps create stable emulsions by bridging oil and water phases without adding a greasy feel.
Common usage levels sit between 2-5% for this ingredient.
Polyglyceryl-3 Polyricinoleate is a plant-derived emulsifier made by combining glycerin and ricinoleic acid.
It works well for giving buttery lip balms and low-viscosity water-in-oil emulsions a non-greasy and pleasant skin feel.
Typical concentrations range from 0.1-3%.
This ingredient is mild and non-irritating in nature.
Because it is derived from ricinoleic acid, this ingredient may not be fungal acne safe. Ricinoleic acid is an unsaturated fatty acid that the Malassezia yeast can metabolize.
Learn more about Polyglyceryl-3 PolyricinoleateEctoin is a compound found naturally in some species of bacteria. It can be synthetically created for skincare use.
This ingredient is an osmolyte; Osmolytes help organisms survive osmotic shock (it protects them from extreme conditions). It does this by influencing the properties of biological fluids within cells.
When applied to the skin, ectoin helps bind water molecules to protect our skin. The water forms a sort of armor for the parts of our skin cells, enzymes, proteins, and more.
Besides this, ectoin has many uses in skincare:
A study from 2004 found ectoin to counteract the damage from UV-A exposure at different cell levels. It has also been shown to protect skin against both UV-A, UV-B rays, infrared light, and visible light.
Studies show ectoin to have dual-action pollution protection: first, it protects our skin from further pollution damage. Second, it helps repair damage from pollution.
In fact, ectoin has been shown to help with:
Fun fact: In the EU, ectoin is used in inhalation medication as an anti-pollution ingredient.
Ectoin is a highly stable ingredient. It has a wide pH range of 1-9. Light, oxygen, and temperature do not affect this ingredient.
The chemical name for this ingredient is Tetrahydromethylpyrimidine Carboxylic Acid.
Learn more about EctoinHydroxyectoin can help to reduce redness.
Isostearic Acid is a fatty acid and a structural cousin of stearic acid. It is an emulsifier.
The branched structure of this ingredient enhances fluidity and gives it a lighter, less greasy feel compared to other fatty acids. It helps improve texture and consistency because it prevents oil and water phases from separating.
This ingredient is sourced from plant-based oils like soybean or rapeseed.
Clinical studies found no signs of irritation from this ingredient.
Since Isostearic Acid is an 18-carbon fatty acid, it is in the range that Malassezia can feed on. This ingredient may not be fungal acne safe.
You might have seen sources that this ingredient is comedogenic. The original comedogenic testing on rabbit ear actually tested the ester, Isopropyl Isostearate and not Isostearic acid itself. There has been no comedogenic testing done on this ingredient, but it may be worth patch testing if you have acne-prone skin.
Learn more about Isostearic AcidLecithin 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 LecithinTrisodium Ethylenediamine Disuccinate is used to help stabilize a product.
It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.
We don't have a description for Quaternium-90 Bentonite yet.
Lavandula Angustifolia Oil is more commonly known as lavender essential oil. It is considered a fragrancing ingredient.
Lavender imparts a famous scent. While the smell is lovely, this ingredient and may sensitize skin in topical products. This is because about 85% of the oil is made up of linalool and linalyl acetate.
When exposed to air, these two compounds become strong allergens. This ingredient exhibits cytotoxicity at low concentrations; amounts of 0.25% have been shown to damage skin cells.
A study from Japan found this ingredient caused lavender sensitivity after widespread exposure.
Lavender essential oil has some antimicrobial, antibacterial, and anti-inflammatory properties. However, the cons of this ingredient may outweight the pros.
More research is needed to confirm lavender essential oil's effects when used in aromatherapy.
Lavandula Angustifolia is known as the English Lavender and famous for creating purple fields in Provence, France.
Learn more about Lavandula Angustifolia OilCitrus Aurantium Dulcis Peel Oil is oil from the peel of an orange fruit.
Limonene and linalool make up the majority of oils from citrus peels. Limonene has a "citrus" fragrance. Citrus peels also contain flavonoids, which have anti-inflammatory properties.
Citrus peel is also a rich source of flavonoids. Flavonoids are natural antioxidants and help protect your skin against damage. Flavonoids are a group of compounds naturally found in vegetables and fruits.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about Citrus Aurantium Dulcis Peel OilTriethyl Citrate comes from citric acid. It has masking, perfuming, and solvent properties. As a solvent, this ingredient helps disperse ingredients evenly in skincare.
One manufacturer claims this ingredient can:
According to perfume manufacturers, this ingredient is almost odorless but has a mild fruity, wine and plum scent. It can be used to mask the scent of other ingredients.
This ingredient can be plant-sourced or synthetic; it can naturally be found in cabbage and white wine.
Learn more about Triethyl CitrateTocopherol 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 TocopherolMalic Acid is an acid with both AHA and BHA properties, but is considered an AHA because its AHA properties are stronger.
It can be naturally found in unripe fruit and especially apples (its name from the latin word "malum", meaning apple!).
Like other AHAs, malic acid gently removes the top layer of dead skin cells to reveal smoother, brighter skin underneath.
Though it’s considered milder and less potent than glycolic or lactic acid, it can help improve:
Due to its larger molecular structure, it penetrates the skin more slowly and is often used in combination with other AHAs to enhance their overall effectiveness.
Malic acid often plays a role in balancing a product’s pH and is usually included in small amounts (around 1-2%) as a supporting exfoliant.
As with all exfoliating acids, you should wear sunscreen daily when using malic acid to protect your newly resurfaced skin.
Fun fact: Malic acid is the compound responsible for the tart flavor of apples and other sour fruits.
While research on malic acid is limited compared to glycolic or lactic acid, it’s still a safe and mild exfoliant.
Read more about some other popular AHA's here:
Learn more about Malic AcidWe don't have a description for Stearyl Triethoxysilane yet.
Chances are, you eat sodium chloride every day. Sodium Chloride is also known as table salt. This ingredient has many purposes in skincare: thickener, emulsifier, and exfoliator.
You'll most likely find this ingredient in cleansers where it is used to create a gel-like texture. As an emulsifier, it also prevents ingredients from separating.
You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.
You might see this ingredient used in scrubs as a primary exfoliating ingredient.
Learn more about Sodium ChlorideEthylhexylglycerin 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 EthylhexylglycerinPhenoxyethanol 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.
Learn more about PhenoxyethanolCi 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 77492Ci 77499 is also hydrated iron III oxide. It is created from mixing red and black iron oxides. This helps give shades of darkness to a product.
Iron III oxides are classified as inorganic chemicals for coloring.
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Where it's from
Kate Somerville is a American brand
50 SPF Rating
With an SPF rating of 50, this product protects against 98.0% of UVB rays
Often compared with
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The data we've presented on this page has been verified by a member of the SkinSort Team.
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