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Ao Reverse Longitude PM Serum-Shot

Ao
Reverse Longitude PM Serum-Shot

Retinal Serum
Uploaded by: timotzara on

Ao Reverse Longitude PM Serum-Shot
Ingredients explained

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. 

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: 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: Sunflower Wax | What-it-does: emollient

A hard wax coming from sunflower that has a high melting point and gives excellent thermal stability to the formulas. Similar to other waxes, it is used to stabilize products and give body to them, or to keep stick type formulas, such as lip balms, solid. 

Retinal - superstar
Also-called: Form of Retinoids, Retinaldehyde | What-it-does: cell-communicating ingredient

If you are reading here, we are pretty sure the words retinoids and retinol ring a bell, but if not, you are seriously missing out, please click here immediately to catch up.  The TL;DR version is that retinoids are the royal family of skincare with tretinoin being the queen, the only FDA-approved ingredient to treat the signs of photoaging. Retinol is like a grandkid, it has to be converted (through two steps) in the skin to become retinoic acid. The conversion means retinol is both less effective and less harsh on the skin. 

So where does our current molecule, Retinal, aka Retinaldehyde fit into the family (btw, here is a nice visual family tree about who is who)?  Remember that retinol needed two conversion steps to become retinoic acid? Yes, you are right, Retinal is the intermediate step between retinoic acid and retinol, meaning it needs only one conversion step to become active in the skin. If we go with our royal family analogy, Retinal is Prince Charles, directly next in line to the throne. 

Once retinal is converted, it becomes retinoic acid and does the same things we detailed in our tretinoin description. In a nutshell, it is everything you expect from an anti-aging superstar such as decreased wrinkles, smoother, firmer and more elastic skin

This sounds good, but how does Retinal compare to retinoic acid? Good question! We found a study (a pretty good one with 125 patients) that compared 0.05% retinal with 0.05% retinoic acid (and vehicle).  They concluded that "at week 18, a significant reduction of the wrinkle and roughness features was observed with both retinaldehyde and retinoic acid." and the difference between the two was not statistically significant. (Interestingly, in both groups, the results were less significant at week 44, so it might be a good idea to have a retinoid break from time to time?) Also, our guy, Retinal was much better tolerated than retinoic acid known for its harshness. 

The good tolerability of retinal was also confirmed by another study that compared retinol (ROL), retinal (RAL) and retinoic acid (RA). They found that "the natural retinoids ROL and RAL do have a good tolerance profile, in contrast with the irritating potential of RA", meaning retinal is an awesome alternative if you have irritation and flaking issues with prescription products, such as Retin-A. 

Last, but not least, we want to mention a pretty big (but subjectively evaluated), Avene (the French pharmacy brand famous for its Retinal products) sponsored study that examined the tolerability and efficacy of a 0.1 Retinal + 6% glycolic acid product in the treatment of acne. The product was added next to the standard anti-acne regimen of 1,709 patients for 90 days and the study concluded that the formula was both very well tolerated as well as effective next to other standard anti-acne medications such as benzoyl peroxide and antibiotics.

Overall, if you are into retinoids, Retinal is a really awesome and well-proven member of the family that is absolutely worth trying. 

Bakuchiol - goodie
Also-called: Sytenol A, Phyto Retinol | What-it-does: cell-communicating ingredient, antioxidant, antimicrobial/antibacterial

At first glance, you could think that Bakuchiol is your average plant extract. It is derived from the seeds of Psoralea Corylifolia, aka Babchi, a plant important in Indian and Chinese medicine. The molecule was first isolated in 1973 and several anti-something properties are known about it: it has anti-inflammatory, antioxidant, anti-tumor, anti-bacterial and hepatoprotective magical abilities like plenty of other Ayurvedic plant extracts.

What makes Bakuchiol a special snowflake is the recent discovery that it behaves on the skin in a way very similar to well-known skincare superstar, retinol. While chemically, it has nothing to do with the vitamin-A family, aka retinoids, comparative gene expression profiling (a fancy way of saying that they compared how retinol and bakuchiol modify the way  skin cells behave and produce important skin proteins such as collagen) shows that retinol and bakuchiol regulate skin cell behavior in a similar way. 

To be more specific, both Bakuchiol and retinol upregulate collagen I, III and IV production and downregulate MMP, the evil collagen attacking enzyme in our skin. This means more collagen stays in our skin and we all know that more collagen equals firmer, more wrinkle-free skin.  A 12-week clinical study using a 0.5% Bakuchiol formula with 17 people using it twice a day confirmed a significant improvement in lines and wrinkles, elasticity, firmness and an overall reduction in photo-damage. Also, the test formula was very well tolerated, without any retinol-like side effects. 

What's more, a 2018 double-blind study with 44 people compared 0.5% Bakuchiol with 0.5% retinol cream and found that "bakuchiol is comparable to retinol in its ability to improve photoaging and is better tolerated than retinol". A super promising result after 12 weeks. 

If you are not a daredevil-type who doesn't want to stop using a super well-proven retinol for a newbie like Bakuchiol, we have good news. The two also work very nicely together and Bakuchiol can actually help to stabilize the otherwise unstable and hard to formulate retinol.

And we are still not done, as Bakuchiol shows not only anti-aging properties but also nice anti-acne effects. 1% Bakuchiol seems to be very effective in itself (57% reduction in acne after 6 weeks treatment) and even better when combined with 2% salicylic acid (67% reduction in acne after 6 weeks). We like that Bakuchiol is such a good team player!  The molecule works against acne in multiple ways: It downregulates 5α-reductase (a sebum-controlling enzyme), it is antibacterial (including P. acnes), anti-inflammatory and it inhibits lipid-peroxidation, an evil oxidative process that is recently thought to be a very early trigger in the acne process. 

We feel that this description is becoming very long so we will just mention that Bakuchiol also seems to positively regulate hydration-related genes such as Aquaporin 3 and also shows some melanin-inhibiting properties

Overall, we think Bakuchiol is an awesome molecule with lots of promise both for anti-aging and anti-acne. But the proof compared to the well-established superstars is far from solid, so in a skincare routine, we would rather add Bakuchiol next to retinol than straight up replace it. Unless you are a gimme-the-newest-shiny-thing-under-the-sun-type. 

Astaxanthin - goodie
What-it-does: antioxidant

An oil-loving, red-orange colored pigment that is becoming more and more well-known as a potent antioxidant.

If being an orange-colored pigment reminds you of beta-carotene from carrots, that is no coincidence: astaxanthin also belongs to the chemical group called carotenoids known for giving yellow, orange, or red color to plants. Our guy comes mostly from microalgae, a well-known and often used source is Haematococcus Pluvialis

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. 

What-it-does: antioxidant, deodorant

We don't have description for this ingredient yet.

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic 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).

Also-called: Jojoba Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0-2

Jojoba is a drought resistant evergreen shrub native to South-western North America. It's known and grown for jojoba oil, the golden yellow liquid coming from the seeds (about 50% of the weight of the seeds will be oil).  

At first glance, it seems like your average emollient plant oil: it looks like an oil and it's nourishing and moisturizing to the skin but if we dig a bit deeper, it turns out that jojoba oil is really special and unique: technically - or rather chemically - it's not an oil but a wax ester (and calling it an oil is kind of sloppy). 

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.

Also-called: Sweet Almond Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1-3

The emollient plant oil that comes from almonds. Similar to other plant oils, it is loaded with skin-nourishing fatty acids (oleic acid - 55-86% and linoleic acid 7-35%) and contains several other skin goodies such as antioxidant vitamin E and vitamin B versions. 

It's a nice, basic oil that is often used due to its great smoothing, softening and moisturizing properties. It's also particularly good at treating dry brittle nails (source).

A superabsorbent polymer (big molecule from repeated subunits) that has crazy water binding abilities. Sometimes its referred to as "waterlock" and can absorb 100 to 1000 times its mass in water. 

As for its use in cosmetic products, it is a handy multi-tasker that thickens up water-based formulas and also has some emulsifying and emulsion stabilizing properties. 

What-it-does: chelating

It’s one of those little helper ingredients that makes sure the product stays the same over time. No color change or anything like that. 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. 

What-it-does: solvent, moisturizer/humectant, perfuming | Irritancy: 0 | Comedogenicity: 0

A nice odorless liquid used mainly as a superior solubilizer and efficacy booster for cosmetic active ingredients such as skincare bigshot vitamin C, self-tanning active DHA or the anti-acne gold standard, benzoyl peroxide

Other than that it can also be used in hair care products where it gives a longer-lasting and more uniform coloring. According to a manufacturer, it might even prevent the formation of split ends.

Also-called: Geogard 111A | What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi and has only milder effect against bacteria. 

It is Ecocert and Cosmos approved, works quite well at low concentrations (0.1-0.6%) and is popular in natural products.

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically.

No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. Has to be combined with some other nice preservatives, like potassium sorbate to be broad spectrum enough.  

In high amounts, it can be a skin irritant, but don’t worry, it’s never used in high amounts.

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

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 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 emollient
A hard wax coming from sunflower that has a high melting point and gives excellent thermal stability to the formulas. Similar to other waxes, it is used to stabilize products and give body to them, or to keep stick type formulas, such as lip balms, solid.  [more]
what‑it‑does cell-communicating ingredient
If you are reading here, we are pretty sure the words retinoids and retinol ring a bell, but if not, you are seriously missing out, please click here immediately to catch up.  The TL;DR version is that retinoids are the royal family of skincare with tretinoin being the queen, the only FDA-approved ingredient to treat the signs of photoaging. [more]
what‑it‑does cell-communicating ingredient | antioxidant | antimicrobial/antibacterial
At first glance, you could think that Bakuchiol is your average plant extract. It is derived from the seeds of Psoralea Corylifolia, aka Babchi, a plant important in Indian and Chinese medicine. [more]
what‑it‑does antioxidant
An oil-loving, red-orange colored pigment known for being a potent antioxidant. [more]
what‑it‑does antioxidant
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does emollient
irritancy, com. 0, 0-2
Jojoba oil - a wax ester (chemically not a real oil), that's very similar to human sebum. It's uniquely excellent at helping the skin with its protective barrier and helping it to stay moisturized. [more]
what‑it‑does emollient
irritancy, com. 0, 1-3
The emollient plant oil that comes from almonds. Similar to other plant oils, it is loaded with skin-nourishing fatty acids (oleic acid - 55-86% and linoleic acid 7-35%) and contains several other skin goodies such as antioxidant vitamin E and vitamin B versions. It's a nice, basic oil that is often used due  [more]
what‑it‑does viscosity controlling | emollient
A big polymer (a molecule from repeated subunits) with crazy water binding abilities. Used as a thickening and emulsion stabilizing agent. [more]
what‑it‑does chelating
It’s one of those little helper ingredients that makes sure the product stays the same over time. No color change or anything like that. 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.  [more]
what‑it‑does solvent | moisturizer/humectant | perfuming
irritancy, com. 0, 0
A nice odorless liquid used mainly as a superior solubilizer and efficacy booster for cosmetic active ingredients such as vitamin C or benzoyl peroxide. [more]
what‑it‑does preservative
A preservative that works mainly against fungi and has only milder effect against bacteria. Popular in natural products.  [more]
what‑it‑does preservative | perfuming | solvent | viscosity controlling
It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically. No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. [more]