How facial oils help your skin – or not!

By Dr. Hannah Sivak | November 27, 2020

Oil is a viscous liquid at ambient temperatures and is both hydrophobic (does not mix with water) and lipophilic (mixes with other oils, literally “fat loving”).

Oils have a high carbon and hydrogen content; most are unsaturated lipids that are liquid at room temperature. Because they are non-polar, oils do not easily adhere to other substances, making them useful as lubricants, so oils are applied to hair to give it a lustrous look, to prevent tangles and roughness.

Don’t get confused: essential oils are not oils!

The word “oil” comes from the word for olive; in fact, common oils are all derived from living beings, plants mostly. Even what we call “mineral oil” is derived from ancient life forms like algae or zooplankton; at the time when petroleum was discovered this was unknown, hence the term “mineral”. The mineral oil used in cosmetics is a specific fraction distilled from crude petroleum. So, new or old, the oils we use are products of life.

The most common oils are those also used in foods (sunflower, maize, olive), but you will also see shea and tucuma butter, coconut oil, palm oil, pumpkin, wheat germ, and many others. The fatty acid composition varies between plant oils, making some more useful than others.

Lipid vs. oil

Lipid is the chemical term for fatty acids, steroids and similar chemicals often found in the oils produced by living things, while oil refers to a mixture of chemicals. Natural oils may also contain chemicals other than lipids, including proteins or waxes (a class of compounds with oil-like properties that are solid at common temperatures) and alkaloids.

The main component of oils is triglycerides. Other common components are phytosterols, polyphenols, squalene, and terpenoids.

Figure: a triglyceride. The fatty acids esterifying glycerol can be different, like here, with linoleic and oleic fatty acids.

Fatty acids

We, humans, use fatty acids as a significant source of energy during metabolism, and as a starting point for the synthesis of phospholipids, the main category of lipid molecules used to construct biological membranes. Cell membranes are crucial to cell life (and health), and fatty acids are crucial to cell membrane structure. Fatty acids, in general, are central to the use of energy in the skin and are required to make new skin and maintain function and health.

An essential fatty acid is one that humans and other animals must obtain from food because the body requires them for good health, and we can’t synthesize them. During evolution, we lost the enzymes desaturases 12 and 15 needed to synthesize them from the saturated fatty acid stearic acid. The chemical structure makes the function possible. Stearic acid cannot do what linoleic acid can because we don’t have the enzymes that can change stearic acid into linoleic acid.

Fatty acids can differ in several ways

The number of carbons in the chain.
Whether they have unsaturated bonds
Number and carbon position of the double (unsaturated) bond (the ω refers to the place of the double bond relative to the #1 carbon in the chain).
The configuration of the unsaturated bond, e.g., cis vs. trans. Why? A “cis” bond bends the chain in space and is very important for the fluidity of cell membranes and response to temperature.

Note: in Nature, you will not usually find “trans” bonds. For this, you have to look at synthetic, hydrogenated fats (look but don’t eat!). Whose idea was it to hydrogenate vegetable oils to make margarine? And who decided that they were healthier than butter? Marketing people.

Only two fatty acids are known to be essential for humans: alpha-linolenic acid, an omega-3 fatty acid) and linoleic acid, an omega-6 fatty acid. Some fatty acids become essential only under particular conditions, e.g. docosahexaenoic acid (an omega-3 fatty acid) and gamma-linolenic acid (an omega-6 fatty acid). At Skin Actives, we use a variety of plant and algae fatty acids to ensure that our skin has an adequate supply of both essential and conditional essential fatty acids.

How to choose an oil

In skincare, oils have become an object of advertising hype just like other ingredients. This would not matter very much except that different oils can have very different effects on your skin.

How to choose a good oil for your skin?

Think about nourishing your skin and NOT the acne bacteria.
Are you looking to alleviate a skin condition like eczema?
What matters to your skin is the fatty acid composition and NOT how pretty the name of the plant might be.
An oil may contain some beneficial impurities, but some impurities may impart a strong odor. I prefer to use purified oils and to add extras as needed.
You will be using minute amounts of oil, choose the type according to your skin needs and not the price
Some oils, like palm oil, may have a high environmental cost, try to avoid them.
Some ω-6 polyunsaturated fatty acids, and their incorporation into membrane phospholipids may favor inflammation. Other fatty acids, such as ω-3 polyunsaturated fatty acids, may decrease inflammation. More evidence is needed before we take this factor into account for formulation.

Special oils for special jobs

Massage stretch marks with Rosehip oil, which by itself will help at prevention and at healing them and has the advantage that you can use it without any worries during pregnancy and lactation.

Taking care of your skin can also help you feel (and get) better sooner. If you take a relaxing bath, apply some rosehip oil afterward so that your skin does not get dry. The skin will feel more comfortable, and you will heal better

It’s a mystery to me why coconut oil became a fad, with highly saturated fatty acids the acne bacteria love it! It is also very bad for your health, it increases LDL cholesterol, an established cause of atherosclerosis and cardiovascular events.

Silicones: skincare products containing silicones are often called “oil-free”. They are oil-free in the sense that silicones can’t be used by the skin, an advantage if you don’t want to feed that acne bacteria but at the same time, these polymers of siloxane will not provide nutrition to the skin or scalp.