Kronans apotek

True Age Retinol Serum

So what the heck is a wax ester and why is that important anyway? Well, to understand what a wax ester is, you first have to know that oils are chemically triglycerides: one glycerin + three fatty acids attached to it. The fatty acids attached to the glycerin vary and thus we have many kinds of oils, but they are all triglycerides. Mother Nature created triglycerides to be easily hydrolyzed (be broken down to a glycerin + 3 fatty acid molecules) and oxidized (the fatty acid is broken down into small parts) - this happens basically when we eat fats or oils and our body generates energy from it.

Mother Nature also created wax esters but for a totally different purpose. Chemically, a wax ester is a fatty acid + a fatty alcohol, one long molecule. Wax esters are on the outer surface of several plant leaves to give them environmental protection. 25-30% of human sebum is also wax esters to give us people environmental protection. 

So being a wax ester results in a couple of unique properties: First, jojoba oil is extremely stable. Like crazy stable. Even if you heat it to 370 C (698 F) for 96 hours, it does not budge. (Many plant oils tend to go off pretty quickly). If you have some pure jojoba oil at home, you should be fine using it for years. 

Second, jojoba oil is the most similar to human sebum (both being wax esters), and the two are completely miscible. Acne.org has this not fully proven theory that thanks to this, jojoba might be able to "trick" the skin into thinking it has already produced enough sebum, so it might have "skin balancing" properties for oily skin.

Third, jojoba oil moisturizes the skin through a unique dual action: on the one hand, it mixes with sebum and forms a thin, non-greasy, semi-occlusive layer; on the other hand, it absorbs into the skin through pores and hair follicles then diffuses into the intercellular spaces of the outer layer of the skin to make it soft and supple.

On balance, the point is this: in contrast to real plant oils, wax esters were designed by Mother Nature to stay on the surface and form a protective, moisturizing barrier and jojoba oil being a wax ester is uniquely excellent at doing that.

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.  

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).

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. 

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: 

• Retinyl Propionate: the most promising retinol ester out there
• Retinyl Retinoate: a super interesting retinol-retinoic acid hybrid molecule
• Tretinoin: the FDA-proven, well-known active ingredient
• Retinol: the good old vitamin A molecule
• Retinyl Palmitate: a super common, but our least fav member of the retinoids

So Astaxanthin's main thing is being an antioxidant. You can take it as a supplement or slather it on your skin, it works both ways. A mouse skin study from 2012 found that a liposomal Astaxanthin formula prevented UV‐induced skin damage in multiple ways: UV-induced skin thickening, collagen reduction, and melanin formation were all hindered or prevented when the skin was pretreated with the Astaxanthin formula. 

Another study from 2012 examined the cosmetic benefits of Astaxanthin and found that combining oral supplementation (6mg/day) and topical application for 8 weeks in 30 volunteers showed improvements in skin wrinkle (crow’s feet), age spot size (cheek), elasticity (crow’s feet), skin texture (cheek) and moisture content of the skin (cheek).  If that would not be enough, a 2017 mouse study found our carotenoid molecule to be effective in speeding up wound healing.

Overall, Astaxanthin is an up and coming antioxidant nice to spot on any ingredient list. 

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.

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.

Chemically speaking, it is an unsaturated (has double bonds) hydrocarbon (contains only carbon and hydrogen) molecule, that can undergo oxidation. On the pro side, this means that squalene can act as an antioxidant (while its no-double-bond version sister, squalane cannot), but on the con side, squalene is less stable and has a shorter shelf life.

This is probably the main reason why its no-double bond and hence more stable sister, squalane shows up more often on ingredient lists. Read about squalane here >>