Fatty acids, like all other ingredients, are what their chemistry says.
Cell membranes are crucial to cell life (and health), and fatty acids are crucial to cell membrane structure. Deficiency in essential fatty acids shows as dermatitis. In general, fatty acids are central to the use of energy in the skin and are required to make new skin and maintain function and health.
A fatty acid (example: palmitic acid) has a carboxylic acid attached to a long hydrocarbon chain. 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 (generally composed of two fatty acids linked through glycerol phosphate to one of a variety of polar groups).
The chemical structure makes the function possible. Stearic acid cannot do what linoleic acid can.
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 cell membranes’ fluidity 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.
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, which are needed to synthesize them from the saturated fatty acid stearic acid.
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 (like illness), for example, docosahexaenoic acid (an omega-3 fatty acid) and gamma-linolenic acid (an omega-6 fatty acid). At Skin Actives, we use various plant and algae fatty acids to ensure that our skin has an adequate supply of both essential and conditional essential fatty acids.
Figure: linoleic acid, an essential fatty acid abundant in pitaya oil. Note the position of the double bonds relative to the omega Carbon 1).
Marketing will try to make you forget the chemistry and make your brain think “X is good for me, X is good for nature”. Never trust marketing, you are not their client, you are just “the public”.
Marketing managed to make people think that coconut oil is good for your health. It isn’t. Clinical trials show that, compared with other vegetable oils, coconut oil increases low-density lipoprotein cholesterol —the “bad” kind that ups cardiovascular disease risk—while offering no improvements to weight, blood glucose, or inflammation markers. In fact, coconut oil increases LDL cholesterol, an established cause of atherosclerosis and cardiovascular events.
What about your skin? Coconut oil is good for acne bacteria, but not for you. When you buy a product containing oil, think hard about who you want to benefit, your skin, or the bad bacteria that make teenagers and women of all ages miserable.
If you look at Skin Actives products, you will not find coconut oil.
You will find instead rosehip, pomegranate, and other oils with essential fatty acids, those you need to supplement the fatty acids your body is capable of making. Other oils may not be as good, meaning rich in essential fatty acids, but they are not bad in the sense of clogging your arteries or feeding acne bacteria.
Is coconut all bad? No, it’s “water”, the liquid endosperm, is full of nutrients and vitamins. And if you can have a caipirinha, go for it. Just don’t use the oil.
Don’t trust marketing, trust chemistry.