Capric/caprylic triglycerides, fractionated coconut oil, liquid coconut oil, MCT oil.

It goes by many names, but this ingredient as just as many uses as it does aliases. Those who are following a ketogenic diet or are bodybuilders will be very familiar with its touted benefits for the body, but little is said about how amazing it can be when applied topically. For simplicity's sake I will be referring to it as MCTs or MCT oil.

What is MCT oil?

MCT stands for Medium Chain Triglycerides. I'll go more into detail about what a triglyceride is in other posts about oils and soapmaking, but for now all you need to know is that triglycerides are the main component of animal and vegetable fats. They are also found in the blood, and you may have heard this term before if you've had lab work done to check your cholesterol.

In order to understand why MCT oil is such a versatile ingredient in skincare, we need to examine it under a microscope. Like all lipids, MCT oil is comprised of fatty acids. The 'medium chain' in MCT oil refers to the length of the carbon chain of these fatty acids. Typically they contain fatty acids with carbon chain lengths of 6-10.

Here is an example of caprylic acid, a fatty acid with a carbon chain length of 8 (C8). Each vertex in the molecular structure represents a carbon atom:

The typical composition of MCT oil consists of caproic acid (C6), caprylic acid (C8), and capric acid (C10).

Fun fact: The fatty acids in MCT oil are prefixed with the Latin word 'capra' which means 'goat'. This is because when in free fatty acid form (i.e not tied up in a triglyceride bond) they give off a smell that is reminiscent of goats. Gross :). MCTs are also present in goat milk, an ingredient used often in soapmaking to give soap skin nourishing properties.

Is Fractionated Coconut Oil The Same as MCT Oil?

While many use fractionated coconut oil (FCO) and MCT oil interchangeably, in the most literal sense, no, they are not the same. Coconut oil is the most common source of MCTs, but significant concentrations are also found in palm kernel oil, butter, and goat's milk [3,9]. As such, they can be synthesized from these sources as well as coconut oil. FCO and MCT oil are only synonymous if the MCTs are extracted from coconut oil.

Furthermore, FCO can sometimes contain small amounts of longer chain fatty acids. This isn't always a bad thing, but if you're looking to use MCT oil to treat a  fungal skin condition, it is important that the MCT oil you get is as pure as possible. I'll explain why a bit later.

How and why is it different from unrefined coconut oil?

Right away we can see that coconut oil and MCT oil are very different by sight, smell, and taste. Unrefined coconut oil is solid at room temperature, appears white or pale yellow, and it has the aroma and flavor of coconuts. By contrast, MCT oil is a clear liquid at room temperature and has very little taste, smell, or color to speak of.

A hint as to why this is comes from one of MCT oil's many names: fractionated coconut oil. In its raw form, coconut oil contains many other fatty acids besides MCTs. The typical profile of coconut oil is also comprised mainly of lauric acid, myristic acid, stearic acid, and palmitic acid [2].

These other fatty acids have longer carbon chains and are solid at room temperature.

During the refining process to create MCT oil, these longer chain fatty acids are removed and the oil becomes 'fractionated', since only a fraction of the original fatty acid profile remains.

What makes MCT oil good for the skin?

Easy Absorption

The same reason MCTs are such good fuel for those on keto and bodybuilders are what makes them such great skin conditioning agents. The shorter length of MCTs fatty acids are more easily absorbed by the body than some other fats [7,4,5]. This is what makes MCT oil easily absorbed by the skin as and gives it a lightweight, non-greasy feel.

Pure MCTs are also highly shelf stable and less prone to rancidity than other vegetable oils.

Hypoallergenic

Due to its highly refined nature, MCTs are considered hypoallergenic for many people. Some who have allergies to other coconut derived ingredients find that they don't have problems with MCT oil because the allergenic components of coconut oil have been removed.

Treats Various Skin Conditions

This is probably my favorite reason for using MCT oil in my daily routine and in my products. MCTs are great at soothing inflammation caused by conditions like eczema, fungal acne, dandruff, and seborrheic dermatitis. This is because many who have these conditions have an overgrowth of a yeast called malassezia in certain areas of the body which can cause itching, flaking, acne, and general suffering. This fungus is able to feed on fatty acids found in the skin, the fatty acids in almost all animal and vegetable oils, AND ingredients derived from those fatty acids like common emulsifiers.

The catch here is that malassezia is a bit of a picky eater, and it can only feed on fatty acids that have a carbon chain length between 11-24 [1]:

MCTs are outside of this range, so the yeast can't feed on it and cause problems. MCTs are one of only three oils that won't feed the yeast. The other two are mineral oil and squalane.

I have a personal vendetta against this yeast because I've always had horrible dandruff. I tried almost everything on the market and it wasn't until I came across F.C's blog, SimpleSkincareScience that I learned about malassezia and what it feeds on. I finally understood why everything I tried only made the problem worse. Most products advertised to fight dandruff contain ingredients that malassezia can feed on.

Antimicrobial

Some types of fungus found on the skin consume fatty acids as a source of carbon [8]. As mentioned above, these fungi can cause dandruff, dermatitis, fungal acne, and other problems. Because MCTs carbon chains are so short, these fungi are unable to feed on them. Studies comparing lauric acid and capric acid have shown that both are anti inflammatory and exhibit inhibitory effects against p. acnes, a bacteria known to cause acne [6]. 

Great Carrier Oil

Given MCT oil's non-greasy, non-pore clogging, non-oxidizing, non-allergy inducing, non-yeast feeding, colorless, odorless properties, it shouldn't be a surprise this stuff makes a great carrier oil. If you're looking to dilute essential oils or make an herb infused oil to level up your cooking, MCT oil is a great choice.

Fun fact: the Green Tea extract used in my products is a homemade herbal infusion of green tea leaves and MCT oil

And that's it! Subscribe to my newsletter to stay up to date on more ingredient spotlight posts!

Sources:

1. A Study of the Fatty Acid Metabolism of the Yeast Pityrosporum ovale

2.Fatty acid profiles of virgin coconut oil

3. Medium Chain Triglyceride Oil Consumption as Part of a Weight Loss Diet Does Not Lead to an Adverse Metabolic Profile When Compared to Olive Oil

4. Short- and medium-chain fatty acids in energy metabolism: the cellular perspective

5. The application of medium-chain fatty acids: edible oil with a suppressing effect on body fat accumulation

6. Anti-bacterial and anti-inflammatory properties of capric acid against Propionibacterium acnes: a comparative study with lauric acid

7. The Use of Medium-Chain Triglycerides in Gastrointestinal Disorders

8. Carbonic anhydrases from pathogens

9. Fatty Acid Profile of Milk - A Review