lalin et la siren

Citron Body Scrub

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.

Let’s start with the easy stuff.  The main components are fragrant molecules, including super common linalool (1-19%), benzyl benzoate (2-10%) and several others adding up to a max amount of 37.6% of EU sensitizers. The most expensive Extra grade is the most fragrant (has more benzyl acetate and cresyl methyl ether) and is used in high-end perfumes, while the First and Second grades are less fragrant, and used mainly in cosmetics.   

Other than smelling nice and making cosmetic formulas also smell nice, Ylang Ylang might have some antimicrobial and antioxidant benefits and also works as an insect repellent. Its nice smell is also commonly known as being relaxing and calming (also backed up by a few recent studies), but it is an aromatherapy use case (when inhaled) so this probably does not count much skincare-wise. 

On the other hand, the nice smell also means allergen fragrant components and 37.6% of EU sensitizers counts as quite high and the oil is considered to have high skin sensitization potential. It is a good idea to avoid if your skin is sensitive.