Alpha-H

Vitamin A Serum

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.

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 >> 

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.

As for the skin, it's a great hydrating plant oil, that can also reduce inflammation and irritation. It's a superb healing agent that can truly help dry skin, not just on the surface by covering it (and not letting water to evaporate) but by initiating structural changes within the skin. If that's not enough, it also helps skin cell regeneration. 

All in all, a real goodie especially for dry, easily irritated skin.

As Dr. Fulton (the scientist behind both Retin-A and RP) puts it in his patent paper,  "Other esters of vitamin A obtained from, for example, palmitic acid and acetic acid do not have the therapeutic advantages found with vitamin A propionate ..... Presumably, the [Retinyl Palmitate] molecule is so large, it is not able to transdermally reach the necessary part of the skin for activity. Similarly, vitamin A acetate is too small molecularly and therefore easily recrystallizes from any solution.....vitamin A propionate is the appropriate molecular weight and configuration to both remain in a stable solution and to be transdermally delivered to a site where it is active." So while the effectiveness of other retinol esters is highly questionable, Retinyl Propionate seems to be the most effective retinol ester molecule, and it "unexpectedly provides all the benefits of vitamin A acid but minimizes the negative side effects", at least according to Dr. Fulton, the inventor of the molecule. 

We know what you are thinking! This sounds great and all, but what about some proof? Some backup data not from the inventor himself?  We looked into it and found three studies working with Retinyl Propionate.

In a 2007 study by Dr. Draelos, she references a 12-week, double-blind, placebo-controlled clinical trial that compared the effectiveness of 0.15% retinol with 0.3% Retinyl Propionate. Both actives were effective in reducing the appearance of facial wrinkles and hyperpigmentation and the 0.3% RP worked a bit better. 

Another research that was done by Procter & Gamble combined multiple anti-aging actives including niacinamide, peptides and 0.3% of Retinyl Propionate and they compared this regimen with a 0.02% tretinoin regimen. They found that the cosmetic regimen was tolerated better, worked faster and gave comparable results. All this sounds very promising for RP, however, it is hard to know how much the other actives contributed to the positive results. 

Last, but not least there is a study from 1998 that tested a 0.15% Retinyl Propionate cream and after 24 weeks found no statistically significant difference between the effects of the retinyl propionate cream and the placebo preparation for any of the clinical parameters of skin photoaging. However, after 48 weeks, the 0.15% RP worked wonders for actinic keratoses, a rough, scaly patch caused by UV damage (its name contains actinic, but it is not acne, has nothing to do with it (!)).

So, it seems that the minimum effective dose of Retinyl Propionate is larger than 0.15% which is not surprising given that it has to do three conversion steps to reach the active form, retinoic acid. But 0.3% RP (or more, obvs) seems to be an effective dose, and even though the proof is not as solid as it is for retinol itself, if you are looking for a more gentle alternative, or if you are in the mood for experimentation, Retinyl Propionate looks like a noteworthy alternative and the most promising option among retinol esters.

There is also some research showing that citric acid with regular use (think three months and 20% concentration) can help sun-damaged skin, increase skin thickness and some nice hydrating things called glycosaminoglycans in the skin. 

But according to a comparative study done in 1995, citric acid has less skin improving magic properties than glycolic or lactic acid. Probably that’s why citric acid is usually not used as an exfoliant but more as a helper ingredient in small amounts to adjust the pH of a formulation.