Smart Custom-Repair Serum (Discontinued)
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Clinique Smart Custom-Repair SerumIngredients explained
Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
A clear, colorless and odorless, highly volatile (meaning it does not absorb into the skin but evaporates from it) liquid that's used as an emollient. It gives a nice non-oily light skin feel and it can improve the slip of the formula without leaving a tacky residue behind.
It's also popular in make-up products as its volatility makes mascaras and foundations last longer. If that would not be enough, it's also an excellent solvent, and it's a regular not only on the ingredients lists of make-ups but also on makeup removers.
Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.
As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity.
As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types).
A super commonly used 5 unit long, cyclic structured silicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel.
It's often combined with the non-volatile (i.e. stays on the skin) dimethicone as the two together form a water-resistant, breathable protective barrier on the skin without a negative tacky feel.
A type of silicone elastomer (rubber-like material with both viscosity and elasticity) whose major function is forming a nice film on the skin.
It is also cosmetically very elegant with a non-tacky, non-oily and smooth skin feel. It also works as a stable delivery system of active materials, has sebum absorption and control properties and upon application, it transforms into a matte appearance with a powdery after feel.
Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.
BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.
It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.
A form of skincare superstar, vitamin C. If you do not know why vitamin C is such a big deal in skincare, we have a really detailed, geeky description that's good to read. :)
So now you know that because pure vitamin C is such a diva (very unstable and hard to formulate) the cosmetic industry is trying to come up with some derivatives that have the badass anti-aging properties of vitamin C (antioxidant protection + collagen boosting + fading hyperpigmentation) but without the disadvantages. This is a hard task, and there is not yet a derivative that is really proven to be better in every aspect, but Ascorbyl Glucoside is one of the best options when it comes to vitamin C derivatives. Let's see why:
First, it's really stable and easy to formulate, so the problems that come with pure vitamin C are solved here.
Second, in vitro (meaning made in the lab, not on real humans) studies show that ascorbyl glucoside can penetrate the skin. This is kind of important for an anti-aging ingredient to do the job, so this is good news, though in-vivo (made on real humans) studies are still needed.
Third, in-vitro studies show that after ascorbyl glucoside is absorbed into the skin it is converted to pure vitamin C (though the rate of conversion is still a question mark). It also shows all the three anti-aging benefits (antioxidant protection + collagen boosting + fading hyperpigmentation) that pure vitamin C does.
Bottom line: ascorbyl glucoside is one of the best and most promising vitamin C derivatives that shows similar benefits to that of pure vitamin C, but it's less proven (in vivo vs. in vitro studies) and the extent of the benefits are also not the same.
A silicone emulsifier that helps water and silicone oils to mix nicely together. It can also be used together with plant oil + silicone oil mixtures.
A clear viscous polymer (a molecule from repeated subunits) liquid that works as a solvent and humectant.
According to manufacturer info, it's recommended for all kinds of washing products (like hand dishwashing detergents or fine-fabric washing powders) and is ideal as a viscosity regulator, detergent booster, and solubilizer.
We don't have description for this ingredient yet.
We don't have description for this ingredient yet.
A traditional Chinese herbal medicine loaded with potent antioxidant and anti-inflammatory flavonoids such as baicalin, baicalein, and wogonin.
If that would not be enough, Skullcap Root is also claimed to have antimicrobial and antifungal properties (also against P.acnes and Malassezia furfur) as well as some skin-brightening activity. A multi-functional skin-goodie.
Cucumber is a nice, non-irritating plant extract that’s known for it’s soothing and emollient properties. It’s not something new to put it on our face: even Cleopatra used it to “preserve her skin”.
It’s commonly believed that cucumber is the answer to puffy eyes, but there is no research confirming this. What research does confirm is that it contains amino acids and organic acids that’s helpful for the skin’s acid mantle. There is also an enzyme (called shikimate dehydrigenase) in the pulp that’s shown to have anti-inflammatory properties.
We have to admit that Algae Extract is not our favorite ingredient name. It does comply with the INCI standard (the official list about how ingredients on the product labels have to be called, the thing we help you to decode here :)), but there are about 20 000 different kinds of algae and an extract from them can be made in another 10 000 ways.
So, Algae Extract can be anything from La Mer's "Miracle Broth" to a simple brown algae extract that helps to smooth the hair. The official description in the Europiean Cosmetic Ingredient listing is this: "an extract of various species of Algae; Extract of the Seaweed, Fucus vesiculosus, Furaceae". Its official functions include being a humectant (helps skin to attract water), emollient (makes skin feel smooth and nice) and skin conditioner (a catchall phrase for saying it does something good for the skin).
A 2015 research paper on the potential of uses of algae in cosmetics summarizes that algae are rich sources of biologically active metabolites including antioxidants, anti-inflammatory agents, alginates, polysaccharides, and carotenoids. Currently, algae extracts are mostly used as moisturizing and thickening agents, but algae also have great potential to combat skin aging, pigmentation as well as working as an antimicrobial.
We have also browsed through Prospector to see what manufacturers say about their algae. There is, for example, an algae extract trade-named Lanablue that comes from blue-green algae (green algae is rare, less than 1% of the total macroalgae in the world) and is claimed to have retinoid like effects (i.e. reduce wrinkles, smooth skin) but without the side effects (though it seems now that the INCI name of Lanablue was changed to Aphanizomenon Flos-Aquae Extract).
There is another algae extract from another manufacturer that comes from red algae (much more common, about 40% of total macroalgae worldwide) and is claimed to have not only moisturizing but also skin smoothing and densifying effects.
Here is a brown algae extract (the most common type, about 59% of macroalgae), also just called Algae Extract on the product label that is simply claimed to be a free radical scavenger, aka antioxidant. These were just three random examples from three manufacturers all called Algae extract even though they all come from different algae with different claims.
Anyhow, the point is this; there are tons of different types of Algae Extracts out there. Unless the brand tells you what they use, it's impossible to know for sure. The most probable scenario for the Alge Extract is that it works as a moisturizer and emollient and it might have some additional anti-aging properties.
We don't have description for this ingredient yet.
When it comes to grape and skincare, the seed extract and the seed oil steals most of the show. The reason for that is that the seed contains the majority of the skin goodies, the antioxidant superstar polyphenols.
The fruit also contains some, but it's less potent. However - according to manufacturer info - the fruit extract is not only an antioxidant, but it's also a soothing, moisturizing and nourishing agent.
We don't have description for this ingredient yet.
It's a plant extract that comes from wheat germ. Used as skin- and hair conditioner and skin protectant.
Contains gluten, if you are allergic.
- A natural moisturizer that’s also in our skin
- A super common, safe, effective and cheap molecule used for more than 50 years
- Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
- Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
- High-glycerin moisturizers are awesome for treating severely dry skin
We don't have description for this ingredient yet.
You probably know yeast from the kitchen where you put it into milk with a little sugar and then after a couple of minutes brownish bubbles form. That is the fungi fermenting the sugar.
As for skin care, yeast contains beta-glucan that is a great soothing ingredient and also a mild antioxidant. The yeast extract itself is a silky clear liquid that has some great moisturizing, skin protecting and film-forming properties on the skin.
If you see a cosmetic product that claims that it has "Botox-like effect" then two things are almost certain: one, the product overpromises and two, it contains Argireline.
So this one is the famous peptide that's marketed by its manufacturer as the "Botox in a jar". The basis for this claim is that it targets the same wrinkle forming mechanism (wrinkles caused by facial muscle movement) as Botox, but the way it works is very different. In addition, the extent to which it can prevent muscles from contracting (and to smooth wrinkles) is very different (otherwise why would anyone use still Botox?).
The manufacturer did several studies to prove that Argireline really works and it does (just not as well as Botox). In-vivo (made on real people) tests showed that using 10% Argireline solution around the eyes for 15 days decreased wrinkles depth by 17%, while a 5% Argireline formula applied for 28 days did almost the same with a decrease in wrinkle depth by 16.26%. A Spanish University also did some research and found that Argireline increased the level of skin moisturization and decreased both the depth and width of wrinkles "significantly".
This means, Acetyl Hexapeptide-8 does have some ability to smooth wrinkles (but not as well as Botox - sorry, if we sound like a broken record). Also, we have to agree with TruthInAging, that it's not a collagen builder and not a preventer of structural aging (think vitamin C, AHAs or retinol); it's just a quick fix. If you are looking for one, this could be your thing. If you are more of a "let's treat this aging thing properly" type, then it's probably not your thing.
A six amino acid peptide that is claimed to improve firmness and skin tone. Its amino acid sequence is Val-Gly-Val-Ala-Pro-Gly that is also called the "spring fragment" and is repeated six times in the important skin protein, elastin molecule.
The manufacturer made a double-blind, one-month long clinical study on 10 women and found that twice a day application of 4% Biopeptide El improved skin firmness by 33% and skin tone by 20%.
Protein fragments, aka peptides and growth factors derived from milk (whey). It is claimed to boost the production of important extracellular matrix components (the gooey stuff between the skin cells) such as hyaluronic acid, collagen I and fibronectin. The in-vivo (made on people) tests showed reduced wrinkles and improved firmness within two weeks by using 0.5% of Whey Protein.
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula.
We don't have description for this ingredient yet.
It's one of the important lipids that can be found naturally in the outer layer of the skin. About 25% of the goopy stuff between our skin cells consists of cholesterol. Together with ceramides and fatty acids, they play a vital role in having a healthy skin barrier and keeping the skin hydrated.
Apart from being an important skin-identical ingredient, it's also an emollient and stabilizer.
We don't have description for this ingredient yet.
- It's one of the gold standard ingredients for treating problem skin
- It can exfoliate skin both on the surface and in the pores
- It's a potent anti-inflammatory agent
- It's more effective for treating blackheads than acne
- For acne combine it with antibacterial agents like benzoyl peroxide or azelaic acid
A light, velvety, unique skin feel liquid that is a good solvent and also makes the skin feel nice and smooth (aka emollient). It's often used in makeup products mixed with silicones to give shine and slip to the product. It's also great for cleansing dirt and oil from the skin as well as for taking off make-up.
We don't have description for this ingredient yet.
We don't have description for this ingredient yet.
Hello, our favorite molecule that helps us wake up in the morning and then keeps us going through the day. As a super well-known stimulant from coffee, tea and plenty of other soft drinks, Caffeine needs no introduction. So we will skip right to the part where we talk about what the hell it does in so-so many cosmetic products.
Looking at the research, we were surprised to find how versatile Caffeine is. It is a small, water-loving molecule with pretty good skin penetration abilties. Once in the skin, it has nice antioxidant properties, meaning that it reduces the formation of evil free radicals and it might even be useful in preventing UV-induced skin cancers.
A well-known thing about Caffeine is that it improves the microcirculation of the blood vessels. Though conventional wisdom and anecdotal evidence says that this property is helpful for dark under-eye circles and puffy eyes, we have to mention that the double-blind research we have found about a 3% caffeine gel concluded that "the overall efficacy of the selected caffeine gel in reducing puffy eyes was not significantly different from that of its gel base." But you know, the proof is in the pudding.
Another thing Caffeine is used for in body care products is its anti-cellulite effects. In theory, it can speed up the lipolysis process (the "fat burning" by our cells) and stimulate the draining lymph system that might lead to the improvement of cellulite. But here again, the evidence that it actually makes a measurable, let alone visible, improvement on actual human beings is limited (we could find only some animal skin studies or caffeine being combined with other actives).
Last, but not least, we have to write about caffeine and hair growth. The theory is that it can inhibit the activity of the 5-α-reductase enzyme that plays an important role in hair loss and allows a renewed growth phase of the hair. We have found some recent and promising research to back this up. A 2017 study compared a 0.2% caffeine liquid with a 5% Minoxidil (an FDA approved active to treat baldness) solution and found that "a caffeine-based topical liquid should be considered as not inferior to minoxidil 5% solution in men with androgenetic alopecia", or English translation means that the caffeine liquid was pretty much as good as the FDA-approved Minoxidil stuff. Not bad!
Overall, we think that caffeine is a very versatile and biologically active ingredient. Even though some of its effects are more hyped up than backed up, it is still a nice to have on many ingredient lists.
It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version.
According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E.
An amino acid sugar that can be found in the skin and does there good and important things. One of them is that it's a precursor for the biosynthesis of superstar moisturizer, hyaluronic acid. So acetyl glucosamine itself is also an important skin-identical ingredient and natural moisturizing factor.
But that is not all, acetyl glucosamine has two other great properties proved by double-blind clinical trials. First, it's a promising ingredient against wrinkles: 2% can improve wrinkles, particularly in the eye area.
Second, the same amount can also fade - always stubborn - brown spots. (Do not expect magic, though - the photos from the study show the difference after 8 weeks of daily use. The difference is visible, but not that big. It's always good to have realistic expectations. :)) Combined with skincare superstar niacinamide the duo is synergistic and is more effective at improving hyperpigmentation, so if you are after the skin-lightening benefit look out for products that contain both.
It’s a handy multi-tasking ingredient that gives the skin a nice, soft feel. At the same time, it also boosts the effectiveness of other preservatives, such as the nowadays super commonly used phenoxyethanol.
The blend of these two (caprylyl glycol + phenoxyethanol) is called Optiphen, which not only helps to keep your cosmetics free from nasty things for a long time but also gives a good feel to the finished product. It's a popular duo.
We don't have description for this ingredient yet.
We don't have description for this ingredient yet.
Synthetic Fluorphlogopite is the synthetic version of the super commonly used mineral, Mica. The advantage of being synthetic is that it has a more consistent quality, fewer impurities and an even lower heavy metal content than Mica (not that Mica's heavy metal content is high). It is also more transparent and has improved light reflection.
The two main use cases for Synthetic Fluorphlogopite is being used neat as a superior "filler" or skin tone enhancer or it can also serve as a base for multi-layered, composite pigments such as pearl effect pigments where it is coated with one or more layers of metal oxide, most commonly titanium dioxide.
We don't have description for this ingredient yet.
It's a little helper ingredient that helps to set the pH of the products to be right. It has an alkaline pH and can neutralize acidic ingredients.
A common little helper ingredient that helps water and oil to mix together, aka emulsifier.
The number at the end refers to the oil-loving part and the bigger the number the more emulsifying power it has. 20 is a weak emulsifier, rather called solubilizer used commonly in toners while 60 and 80 are more common in serums and creams.
It’s the - sodium form - cousin of the famous NMF, hyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here. The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.
As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution".
In spite of this, if you search for "hyaluronic acid vs sodium hyaluronate" you will find on multiple places that sodium hyaluronate is smaller and can penetrate the skin better. Chemically, this is definitely not true, as the two forms are almost the same, both are polymers and the subunits can be repeated in both forms as much as you like. (We also checked Prospector for sodium hyaluronate versions actually used in cosmetic products and found that the most common molecular weight was 1.5-1.8 million Da that absolutely counts as high molecular weight).
What seems to be a true difference, though, is that the salt form is more stable, easier to formulate and cheaper so it pops up more often on the ingredient lists.
If you wanna become a real HA-and-the-skin expert you can read way more about the topic at hyaluronic acid (including penetration-questions, differences between high and low molecular weight versions and a bunch of references to scientific literature).
We don't have description for this ingredient yet.
It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life.
It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.
Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.
The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >>
A vitamin C derivative that's created by combining ascorbic acid (pure vitamin C) with a molecule called 3-APPA (it stands for 3-aminoproply dehydrogen phosphate). If you do not know what the big deal about vitamin C is, you are missing out, and you have to click here and read all the geeky details about it.
So now, you know that vitamin C is awesome. It's proven to have antioxidant, collagen-boosting and skin-brightening magic abilities, but the problem is that it's really really unstable. To solve the stability issue, the cosmetic industry is coming up with derivatives and Aminopropyl Ascorbyl Phosphate (AAP) is a newish version created by a Korean company.
According to the manufacturer, AAP is a water soluble, stable derivative that has both anti-wrinkle and whitening effects. They conducted an in-vivo (made on real people) study with 33 participants and found that the test formula, with just 0.5% AAP, "significantly" reduced hyperpigmentation (age spots) after 8 weeks (by 29-33%). They also measured a "dramatic" decrease in the total number of wrinkles, about 23% after 8 weeks. (If that's dramatic, we are not sure. Also, be patient because after 4 weeks, the wrinkle reduction was only a couple of percent.)
As for published studies on AAP, we found hardly anything. We found one done by Estee Lauder that briefly mentions AAP as an antioxidant that adds additional UV protection to sunscreen formulas. Another one done by Oriflame reviewed skin-whitening ingredients and also briefly mentioned AAP as a skin-lightening active.
Overall, there is not much data on Aminopropyl Ascorbyl Phosphate, but it does seem like a promising derivative with antioxidant, anti-wrinkle and skin-brightening properties. If you are into vitamin C derivatives and are happy to experiment, it's worth a go.
A kind of polymer (big molecule from repeated subunits) that helps to create beautiful gel-like textures. It's also a texturizer and thickener for oil-in-water emulsions. It gives products a good skin feel and does not make the formula tacky or sticky.
It works over a wide pH range and is used between 0.5-1.2%.
A smallish polymer molecule (created from repeated units of Polyethylene glycol, aka PEG) that's used as a solubilizer and viscosity control agent.
It is a clear, colorless liquid that is water-soluble and water-binding (aka humectant) and can help to solubilize sparingly-water soluble things (e.g. vanilla, perfumes) into water-based formulas. Thanks to its water-binding ability, it also prevents the drying out of formulas, especially when combined with the fellow hygroscopic agent, sorbitol.
A very common ingredient that can be found in all cell membranes. In cosmetics it's quite the multi-tasker: it's an emollient and water-binding ingredient but it's also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.
Similar to other glycols, it's a helper ingredient used as a solvent, or to thin out thick formulas and make them more nicely spreadable.
Hexylene Glycol is also part a preservative blend named Lexgard® HPO, where it helps the effectiveness of current IT-preservative, phenoxyethanol.
A kind of polymer (big molecule from repeated subunits) that helps to thicken up and stabilize products. It usually comes to the formula as part of some thickener complex. For example, coupled with isohexadecane and polysorbate 80, the trio helps to create soft and supple textures.
The unfancy name for it is lye. It’s a solid white stuff that’s very alkaline and used in small amounts to adjust the pH of the product and make it just right.
For example, in case of AHA or BHA exfoliants, the right pH is super-duper important, and pH adjusters like sodium hydroxide are needed.
BTW, lye is not something new. It was already used by ancient Egyptians to help oil and fat magically turn into something else. Can you guess what? Yes, it’s soap. It still often shows up in the ingredient list of soaps and other cleansers.
Sodium hydroxide in itself is a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totally harmless.
Far from the tin cans you find in the supermarket, Tin Oxide is mostly used when dealing with so-called effect pigments, tricky composite pigments that can do color travel (change color depending on the viewing angle) or give multiple color effect.
It's often found alongside Mica (as a base material) and Titanium Dioxide (as a coating) to give a glossy, pearlescent effect. Together, they make up a trademarked technology called RonaFlair Blanace from the German manufacturer Merck. According to their info, this combination can balance out undesirable tones in the skin, making it a popular choice for brightening products and highlighters.
Other than that, CosIng (the official EU INCI database) lists its uses as being a bulking agent (to increase the volume of products), as well as a physical exfoliant or an opacifying agent, but being part of composite effect pigments is a much more common use case.
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.
It is typically used in tiny amounts, around 0.1% or less.
We don't have description for this ingredient yet.
It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.
It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic.
Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10).
It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.
Ci 19140 or Tartrazine is a super common colorant in skincare, makeup, medicine & food. It’s a synthetic lemon yellow that's used alone or mixed with other colors for special shades.
FDA says it's possible, but rare, to have an allergic-type reaction to a color additive. As an example, it mentions that Ci 19140 may cause itching and hives in some people but the colorant is always labeled so that you can avoid it if you are sensitive.
A common colorant that gives products a nice red color.
Titanium Dioxide is one of the two members of the elite sunscreen group called physical sunscreens (or inorganic sunscreens if you’re a science geek and want to be precise).
Traditionally, UV-filters are categorized as either chemical or physical. The big difference is supposed to be that chemical agents absorb UV-light while physical agents reflect it like a bunch of mini umbrellas on top of the skin. While this categorization is easy and logical it turns out it's not true. A recent, 2016 study shows that inorganic sunscreens work mostly by absorption, just like chemical filters, and only a little bit by reflection (they do reflect the light in the visible spectrum, but mostly absorb in the UV spectrum).
Anyway, it doesn't matter if it reflects or absorbs, Titanium Dioxide is a pretty awesome sunscreen agent for two main reasons: it gives a nice broad spectrum coverage and it's highly stable. Its protection is very good between 290 - 350 nm (UVB and UVA II range), and less good at 350-400 nm (UVA I) range. Regular sized Titanium Dioxide also has a great safety profile, it's non-irritating and is pretty much free from any health concerns (like estrogenic effect worries with some chemical filters).
The disadvantage of Titanium Dioxide is that it's not cosmetically elegant, meaning it's a white, "unspreadable" mess. Sunscreens containing Titanium Dioxide are often hard to spread on the skin and they leave a disturbing whitish tint. The cosmetic industry is, of course, really trying to solve this problem and the best solution so far is using nanoparticles. The itsy-bitsy Nano-sized particles improve both spreadability and reduce the whitish tint a lot, but unfortunately, it also introduces new health concerns.
The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, "to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens". The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.
All in all, Titanium Dioxide is a famous sunscreen agent and for good reason, it gives broad spectrum UV protection (best at UVB and UVA II), it's highly stable, and it has a good safety profile. It's definitely one of the best UV-filter agents we have today, especially in the US where new-generation Tinosorb filters are not (yet) approved.
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| what‑it‑does | solvent |
| what‑it‑does | emollient | solvent |
| what‑it‑does | emollient |
| irritancy, com. | 0, 1 |
| what‑it‑does | emollient | solvent |
| what‑it‑does | moisturizer/humectant | solvent |
| irritancy, com. | 0, 1 |
| what‑it‑does | antioxidant | skin brightening |
| what‑it‑does | emulsifying |
| what‑it‑does | moisturizer/humectant | solvent |
| what‑it‑does | perfuming |
| what‑it‑does | emollient |
| what‑it‑does | soothing | antioxidant | antimicrobial/antibacterial | moisturizer/humectant |
| what‑it‑does | soothing | emollient |
| what‑it‑does | emollient | moisturizer/humectant |
| what‑it‑does | soothing | antioxidant | moisturizer/humectant |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | cell-communicating ingredient | moisturizer/humectant |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | antioxidant |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | emulsifying | surfactant/cleansing |
| irritancy, com. | 0, 0 |
| what‑it‑does | skin-identical ingredient | emollient |
| irritancy, com. | 0, 0 |
| what‑it‑does | exfoliant | anti-acne | soothing | preservative |
| what‑it‑does | emollient | solvent |
| what‑it‑does | emollient |
| what‑it‑does | abrasive/scrub |
| what‑it‑does | antioxidant | perfuming |
| what‑it‑does | emulsifying |
| what‑it‑does | antioxidant |
| irritancy, com. | 0, 0 |
| what‑it‑does | skin-identical ingredient | skin brightening |
| what‑it‑does | moisturizer/humectant | emollient |
| what‑it‑does | viscosity controlling |
| what‑it‑does | antioxidant |
| what‑it‑does | viscosity controlling |
| what‑it‑does | buffering |
| what‑it‑does | emulsifying | surfactant/cleansing |
| irritancy, com. | 0, 0 |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | skin-identical ingredient | emollient |
| irritancy, com. | 0, 1 |
| what‑it‑does | antioxidant | skin brightening |
| what‑it‑does | viscosity controlling |
| what‑it‑does | moisturizer/humectant | solvent |
| what‑it‑does | emollient | emulsifying |
| what‑it‑does | solvent | emulsifying | perfuming | surfactant/cleansing |
| irritancy, com. | 0-1, 0-2 |
| what‑it‑does | viscosity controlling |
| what‑it‑does | buffering |
| what‑it‑does | colorant | abrasive/scrub | viscosity controlling |
| what‑it‑does | chelating |
| what‑it‑does | antioxidant |
| what‑it‑does | preservative |
| what‑it‑does | colorant |
| what‑it‑does | colorant |
| what‑it‑does | sunscreen | colorant |