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oskia Retinoid Sleep Serum Level 2

Retinoid Sleep Serum Level 2

Gently yet incredibly effective, OSKIA's ultra-lightweight Retinoid treatment formulated with OSKIA's advanced Super-Nutrient Retinoid Complex (retinoid, vitamin C & E and pro-vitamin D3) with high concentrations of cellular nutrients, plus botanical actives and key anti-oxidants to help maintain a firm, plump, youthful and healthy-looking complexion.
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oskia Retinoid Sleep Serum Level 2
Ingredients explained

What-it-does: solvent, emollient

A biodegradable emollient that gives a fresh gliding sensation and a powdery after feel. It works well with all kinds of oils including natural and silicone oils.

A little helper ingredient that can boost the performance and enhance the delivery of active ingredients in a formula. It can penetrate deep layers of the skin helping actives to do the same.

It's especially useful to help active ingredients for self-tanning (DHA), anti-acne or skin-whitening to penetrate deeper and work better.

What-it-does: emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A handy helper ingredient that helps water and oil to mix nicely together, aka emulsifier. It is especially recommended for protective, baby care and general purpose emollient creams. 

It also helps to disperse insoluble particles (think color pigments or zinc/titanium dioxide sunscreen) nice and even in cosmetic formulas. 

We don't have description for this ingredient yet.

What-it-does: emollient, perfuming

A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.

Also-called: Form of Vitamin C, Ascorbyl Isotetrapalmitate, Ascorbyl Tetraisopalmitate, ATIP;Tetrahexyldecyl Ascorbate | What-it-does: antioxidant, skin brightening

Tetrahexyldecyl Ascorbate is a stable, oil-soluble form of skincare big shot Vitamin C. If you do not know, why Vitamin C is such a big deal in skincare, click here and read all about it. We are massive vitamin C fans and have written about it in excruciating detail.

So now, you know that Vitamin C is great and all, but it's really unstable and gives cosmetics companies many headaches. To solve this problem they came up with vitamin C derivatives, and one of them is Tetrahexyldecyl Ascorbate (let's call it ATIP in short).

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It's a really promising candidate (see below), but while reading all the goodness about it in a minute, do not forget that derivatives not only have to be absorbed into the skin but also have to be converted to pure vitamin C (ascorbic acid or AA) and the efficacy of the conversion is often unknown. In addition, vitamin C's three magic properties (antioxidant, collagen booster, skin brightener) are all properly proven in-vivo (on real people), but for the derivatives, it's mostly in-vitro studies or in the case of ATIP, it's in-vitro and done by an ingredient supplier.

With this context in mind let's see what ATIP might be able to do. First, it is stable (if pH < 5), easy to formulate and a joy to work with for a cosmetic chemist.

Second, because it's oil-soluble, its skin penetration abilities seem to be great. So great in fact, that it surpasses the penetration of pure vitamin C threefold at the same concentration and it penetrates successfully into the deeper layers of the skin (that is usually important to do some anti-aging work). There is also in-vitro data showing that it converts to AA in the skin. 

Third, ATIP seems to have all three magic abilities of pure vitamin C: it gives antioxidant protection from both UVB and UVA rays, it increases collagen synthesis (even more than AA) and it has a skin brightening effect by reducing melanogenesis by more than 80% in human melanoma cell cultures.

So this all sounds really great, but these are only in-vitro results at this point. We could find Tetrahexyldecyl Ascorbate mentioned only in one published in-vivo study that examined the anti-aging properties of a silicone formula containing 10% AA and 7% ATIP. The authors theorized that the 10% AA is released slowly from the silicon delivery system and probably stays in the upper layer of the skin to give antioxidant benefits, while ATIP penetrates more rapidly and deeply and gives some wrinkle-reducing benefits. The study was a small (10 patients), double-blind experiment, and the formula did show some measurable anti-aging results. However, it is hard to know how much pure vitamin C or ATIP can be thanked.

Bottom line: a really promising, but not well-proven vitamin C derivative that can be worth a try especially if you like experimenting (but if you like the tried and true, pure vitamin C will be your best bet).

What-it-does: solvent

We don't have description for this ingredient yet.

Also-called: Turmeric Root Extract | What-it-does: antioxidant, soothing, skin brightening, perfuming

Turmeric is the yellow spice you probably know from curry and Indian food. It's also a traditional herbal medicine used in Ayurveda for its bunch of anti-something magic abilities including being anti-inflammatory, antimicrobial, antioxidant and anticarcinogenic. 

As for turmeric and skincare, we have good news: studies show that the root extract and its main biologically active component, curcumin can do multiple good things for the skin. Thanks to its anti-inflammatory and antimicrobial activity, it shows some promise for acne-prone skin and a small study from 2013 showed that it might be able to regulate sebum production

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It's also a potent antioxidant and skin-brightening agent so it often shows up in anti-aging and/or radiance-boosting products. 

We don't have description for this ingredient yet.

Also-called: Coenzyme Q10 | What-it-does: antioxidant

Thanks to Nivea, Q10 is a pretty well-known ingredient and the fame and Beiersdorf's (the parent company of Nivea) obsession with it are not for no reason. It's an antioxidant found naturally in human cells where it plays a big role in energy production.

In fact, it's so important for energy production that if taken as an oral supplement it has a caffeine-like effect and if taken at night you will probably not sleep very well (so you should take it in the morning). Q10 supplementation is not a bad idea: it not only gives you energy but research also shows that oral Q10 increases the Q10 level of the skin (of course, it decreases with age like pretty much every good thing in the skin) and may help to reduce wrinkles. If you are not for supplements, dietary sources include fish, spinach, and nuts.

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As for skincare, Q10 comes in the form of a yellow, oil-soluble powder that's shown to absorb into the upper layer of the skin and act there like an awesome antioxidant. It not only has preventative effects but might also be able to reduce the depth of wrinkles, though 0.3% Q10 was used in the study that counts as really high (products containing that much should be very yellow!). 

We don't have description for this ingredient yet.

Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

What-it-does: emollient

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

Also-called: Granactive Retinoid, HPR, Form of Retinoids | What-it-does: cell-communicating ingredient

Hydroxypinacolone Retinoate (HPR) is the newest member of the "royal family of skincare" (see who is who on this cool retinoids family tree), the retinoid family. The queen of the family is the FDA-approved anti-aging superstar, retinoic acid, aka tretinoin and HPR seems to be a gentle but influential sister princess to the queen.

It's a so-called retinoic acid ester, meaning that it's directly related to retinoic acid. If you've already read our description about retinol or retinyl palmitate, you know that the active ingredient our skin cells can interpret is retinoic acid. Other forms of retinoids have to be converted by our metabolic machinery to do something. That's not the case with HPR.  It binds directly to the retinoid receptors of the skin cells to work its skincare magic. 

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The big promise of HPR is that it's similarly active as retinoic acid (no conversion needed, remember) but without the irritation. According to the manufacturer's tests, 24 hours of an occlusive patch with 0.5% HPR resulted in significantly lower irritation than 0.5% retinol.  Also, there was a "dramatic reduction of lines and wrinkles" after applying 0.2% HPR around the eyes twice a day for 14 days.

These results sound sooo promising that we don't blame you if you wanna run out right now and get an HPR formula to slather on your face.  But, before you do, you have to know that the info we have about HPR at the moment is mainly from the manufacturer, whose tests may or may not be accurate or properly designed (such as controlled, double-blind and conducted on an appropriate number of people). 

As HPR is pretty new there isn't that much independent research we could find yet. We found two Italian studies both examining the efficacy of HPR combined with other things (retinol in both cases, and papain in one of them) for the treatment of acne. Both studies found the formulas effective but they contained other things too, so it's hard to judge how well HPR did.

Regarding anti-aging, there is a pretty recent, Estee Lauder sponsored study that compared the in-vitro (not on real human beings but on skin models) collagen-boosting effectiveness of Hydroxypinacolone Retinoate, tretinoin, good old retinol and retinyl palmitate (RP). The results are pretty encouraging showing that  "HPR had greater levels of gene transcription than retinol and RP (RP) at the same concentrations ... however, HPR did not achieve gene transcription levels of ATRA (tretinoin)."  But, a much higher dose might be tolerated from HPR and the highest dose of HPR out-performed tretinoin. Pretty encouraging, though we are very much waiting for a study to confirm all this on real human beings.  

Bottom line: We are really happy to see some innovation happening with retinoids, and we think Hydroxypinacolone Retinoate is a super promising rising star, but it’s not fully proven yet. If you are someone who likes to experiment and try out the newest things, grab your running shoes and try some HPR containing serum now (see product list below :)). If you like the tried and true, however, stick to retinol and tretinoin for now and re-examine the question in a couple of years when (hopefully) more research will be available. 

Are you into Retinoids? Read our shiny description about other members of the retinoid family: 

Also-called: Rosemary Leaf Extract | What-it-does: antioxidant, soothing, antimicrobial/antibacterial

The extract coming from the lovely herb, rosemary. It contains lots of chemicals, including flavonoids, phenolic acids, and diterpenes. Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. 

The leaves contain a small amount of essential oil (1-2%) with fragrant components, so if you are allergic to fragrance, it might be better to avoid it. 

We don't have description for this ingredient yet.

Also-called: Sunflower Oil Unsaponifiables | What-it-does: soothing, skin-identical ingredient, emollient

The unsaponifiable part of sunflower oil. It's the small part of the oil that resists saponification, the chemical reaction that happens during soap making.

If you want to understand saponification more, here is a short explanation (if not, we understand, just skip this paragraph): Oils are mostly made up of triglyceride molecules (a glycerin + three fatty acids attached to it) and during the soap making process a strong base splits the triglyceride molecule up to become a separate glycerin and three soap molecules (sodium salts of fatty acids). The fantastic Labmuffin blog has a handy explanation with great drawings about the soap-making reaction. 

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So, the triglyceride molecules are the saponifiable part of the oil, and the rest is the unsaponifiable part. In the case of sunflower oil, it's about 1.5-2% of the oil and consists of skin nourishing molecules like free fatty acids (fatty acids not bound up in a triglyceride molecule, it contains mainly (48-74% according to its spec) barrier building linoleic acid), tocopherol (vitamin E) and sterols.

According to manufacturer's info, it's an oily ingredient that not only simply moisturizes the skin but also has great lipid-replenishing and soothing properties. The clinical study done by the manufacturer (on 20 people) found that a cream with 2% active increases skin moisturization by 48.6% after 1 hour, and 34.2% after 24 hours. Applied twice daily for 4 weeks, the study participants had a major improvement in skin dryness, roughness, and desquamation (skin peeling) parameters.

Also-called: Sunflower Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

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Our intro did get pretty big after all (sorry for that), so let's get to the point finally: sunflower oil - similar to other plant oils - is a great emollient that makes the skin smooth and nice and helps to keep it hydrated. It also protects the surface of the skin and enhances the damaged or irritated skin barrier. Leslie Bauman notes in Cosmetic Dermatology that one application of sunflower oil significantly speeds up the recovery of the skin barrier within an hour and sustains the results 5 hours after using it.

It's also loaded with fatty acids (mostly linoleic (50-74%)  and oleic (14-35%)). The unrefined version (be sure to use that on your skin!) is especially high in linoleic acid that is great even for acne-prone skin. Its comedogen index is 0, meaning that it's pretty much an all skin-type oil

Truth be told, there are many great plant oils and sunflower oil is definitely one of them.

Also-called: Huile Vegetale, Olus Oil;Vegetable Oil | What-it-does: emollient

We don't have description for this ingredient yet.

Lecithin - goodie
What-it-does: emollient, emulsifying

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

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • 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 at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

Also-called: Aqua | What-it-does: solvent

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. 

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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. 

What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi. 

It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.

You may also want to take a look at...

what‑it‑does solvent | emollient
A biodegradable emollient that gives a fresh gliding sensation and a powdery after feel. [more]
what‑it‑does solvent | viscosity controlling
A helper ingredient that can boost the performance and enhance the delivery of active ingredients. It can penetrate deep layers of the skin helping actives to do the same. [more]
what‑it‑does emulsifying
irritancy, com. 0, 1-2
A handy helper ingredient that helps water and oil to mix nicely together. [more]
what‑it‑does emollient | perfuming
A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.
what‑it‑does antioxidant | skin brightening
A stable, oil-soluble form of Vitamin C, that might have (in-vitro results) all the magic abilities of pure vitamin C (antioxidant, collagen booster, skin brightener). [more]
what‑it‑does solvent
what‑it‑does antioxidant | soothing | skin brightening | perfuming
Turmeric Root Extract that has nice anti-inflammatory, antioxidant and skin-brightening properties. [more]
what‑it‑does antioxidant
Q10 - an antioxidant found naturally in human cells where it plays an important role in energy production. As for skincare, it works as an awesome antioxidant that might also be able to reduce wrinkle depth. [more]
what‑it‑does viscosity controlling
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does emollient
A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [more]
what‑it‑does cell-communicating ingredient
The newest member of the retinoid family. Its big promise is that it's similarly active as retinoic acid but without the irritation. For now, it's a very promising but not properly proven active both for anti-aging and acne treatment. [more]
what‑it‑does antioxidant | soothing | antimicrobial/antibacterial
Rosemary leaf extract - Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. [more]
what‑it‑does soothing | skin-identical ingredient | emollient
The small (1.5-2%) part of sunflower oil that resists soap making. It contains valuable skin-nourishing molecules like vitamin E, sterols and fatty acids. It's also claimed to have lipid-replenishing and soothing properties. [more]
what‑it‑does emollient
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does emollient
what‑it‑does emollient | emulsifying
It's quite the multi-tasker: an emollient and water-binding ingredient but also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.  [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [more]