What is a dry oil?
A vegetable oil can thus be described as dry or oily, depending on its ability to penetrate the epidermis.
A dry oil does not leave a greasy film on the skin, it penetrates easily, while providing good skin hydration.
The dry oil thus allows a pleasant application, with an oily feeling to the touch.
There are different dried oils and we must distinguish here dry oils by nature, from those which have become dry by transformation. In the latter case, oils of natural origin are then subjected to a process of transformation of their chemical structure. These include Esterified Oils, whose formula consists of vegetable oil and esters (fatty acid derivatives), which changes their texture.
Esterified oils then become more fluid and light, but are also more stable over time because they are less rancid.
The major drawback of these oils, which are highly processed by industry, is that they lose part of their molecules, in particular the unsaponifiables. They are not as rich in vitamins, sterols, … as virgin oils. Their benefits on the skin are not at all the same, so they are to be distinguished from virgin vegetable oils.
To recognize them, look at the INCI list on the label of your oil. If the terminologies:
– Caprylic / Capric Triglyceride
– Caprylate / caprate
– Oleyl Erucate / Linoleate
– Decyl Oleate
– Dicaprylyl Ether
– Isopropyl Palmitate / myristate
– Isononyl isononanoate
appear, it’s a processed oil.
How do you know if an oil has a dry feel or not?
The oily or dry feeling is directly linked to the fatty acid composition of the oil.
Fatty acids have a greater or lesser affinity with the skin. The more polyunsaturated fatty acids (PUFA) in the oil, the stronger the affinity for the skin and the faster it will penetrate the epidermis.
The 3 fatty acids that are quickly absorbed by the skin are Alpha-linolenic acid (Omega 3), Linoleic acid (Omega 6) and Gamma-linolenic acid (from the Omega 6 family).
It is therefore the vegetable oils mainly composed of omega 3 and omega 6 which are penetrating and qualified as dry oils.
If the sum of these 3 fatty acids exceeds 45%, the mixture will have a dry feel and will be very quickly absorbed.
Take the example of Muscat Rose Oil:
Its composition is as follows:
36% Omega 3
46% Omega 6
14% Omega 9
and 5% Saturated Fat
Its composition in Omega 3 and Omega 6 is equal to 82%, which means that it will penetrate very well into the skin and will have a dry feel.
Conversely, oils rich in monounsaturated fatty acids (MUFA), that is to say Omega 9 and saturated fatty acids (AGS) are fatty oils.
Here are some examples of vegetable oils with a dry or oily feel:
Dry oils: Grapeseed, Muscat rose, Inca inchi, Evening primrose, Borage, Camelina, Flax, or Hemp.
Fatty oils: Avocado, Shea butter, Coconut, Tamanu, or Castor oil.
Note that the notion of dry or fatty oil is completely independent of the comedogenic index. Thus a dry oil can quickly penetrate the skin and therefore be comedogenic, this is the case with Muscat Rose Oil for example. Whereas a fatty oil like avocado is non-comedogenic. You should also take into account the comedogenicity of the oil if you apply it on your face and have a skin prone to blackheads or blemishes.
Why are polyunsaturated fatty acids so well absorbed by the skin?
Simply because they are part of the composition of our stratum corneum. Normally, we provide our skin with the constituents it needs through our diet, which will allow it to regenerate. Except that :
– on the one hand, our diet is often unbalanced and does not provide sufficient quantities of these essential ingredients to the skin
– on the other hand, our organism mobilizes its resources towards the VITAL ORGANS, which are the brain, the heart and the muscles. The skin is then served last.
Which is why it can be in such bad shape. Thus, your skin, lacking these famous fatty acids, will quickly absorb them.
This is why, you can both bring these fatty acids directly to your skin or from the inside with various table oils, such as rapeseed, flax, hazelnut, grape seeds …
What to remember about dry oils:
These oils are particularly rich in Essential Fatty Acids and have excellent qualities for the skin. They have many advantages, since dry oils
– are easily and quickly absorbed by the skin
– reduce the impression of fat from other oils
– suitable for oily skin
– help normalize dry or sensitive skin
– are particularly effective for skin prone to eczema, psoriasis or acne.
Dry oils do not always offer a smooth and soft feeling when applied. Some more “rough” like those of Safflower, Camelina, Hemp, Borage can be associated with a smooth oil (Sweet almond, Coconut, Apricot, Macadamia, Muscat rose) especially in case of very sensitive skin or for babies.
Finally, don’t forget that dry oils are often fragile! This is why they must be stored with great care to limit oxidation. To optimize their conservation and benefit from all the qualities of these oils, it is possible to add a few drops of vitamin E to the bottle, but above all to keep them away from light and heat.