Essential Oils, Carrier Oils, Macerated Oils: What They Are & How To Tell The Difference

What is an essential oil? What about a carrier oil? Or a macerated oil?

​All of these oil types can come from the same plant but work completely differently.
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Using any oil the wrong way could make it ineffective or even dangerous. So here's exactly how to tell an essential oil from a carrier oil, and a base oil from an infused oil or macerated oil.

​What are essential oils, carrier oils and macerated oils?

Ever tried calendula oil in your hair?

Hmmm... would that be the essential oil or the macerated oil?

When we call all oils from the same plant by the same name, things can get confused very quickly.

Even when they come from the same plant, the oil type makes all the difference. Essential oils are very different from carrier oils, which are very different from macerated oils or infused oils. Here's how to tell the difference and get the best out of each type of oil.

What are essential oils?

Essential oils are concentrated, aromatic oils derived from plants. They're also called plant essences and can come from pretty much any part of the plant, from the flowers, to the leaves, the fruits, stems, twigs, barks, seeds, roots... you get the picture.
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Used for over 6000 years, they played a big role in medicine until the modern focus on single component drugs began, in the late 19th century. These days, essential oils are making a huge comeback. As alternative health becomes mainstream, both within self-care and conventional medicine, knowledge and interest in these powerful plant extracts is growing.

There are over 3000 known essential oils. Image by Kelly Sikkema.

Over 3000 essential oils have been found and there are now hundreds of scientific studies confirming the anti-inflammatory, antimicrobial, growth-stimulating, soothing and antioxidant properties they've traditionally been used for - all of which make them a great option for your haircare regimen.

How are essential oils made?

They're usually extracted from plants by (steam) distillation or pressure. In fact, if an oil isn't extracted either of those ways, then it's not really an essential oil:

​According to the International Organization for Standardization, better known as ISO,  'essential oils' is a term reserved for plant oils obtained either "by distillation with water or steam, or from the epicarp of citrus fruits by a mechanical process, or by dry distillation".

Essential oils can be extracted from the peel of citrus fruits. Miguel Maldonado.

​While solvents are sometimes used to extract more delicate oils which can't be distilled, technically the oil this produces isn't really an essential oil.

​How to use essential oils

When it comes to haircare, essential oils are usually used for scalp care. Several of them help hair grow faster or thicker. Others deal with itchy scalps, dandruff and various skin complaints that affect the scalp.
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To use most essential oils on your scalp, you'll need to dilute them first in a carrier oil (see below) since they're so concentrated. With a handful of exceptions, you should never use essential oils without diluting them first. As powerful as these essences are, most are effective at pretty low concentrations, like 1-3%, so there's no need to use a whole lot anyway.

​Once your essential oil is safely diluted, just take some in your fingers and massage it into your scalp. You can leave it in a few hours to overnight and then wash out in the morning, or if you have dry hair that likes oils, you can leave it in (if your hair hates oils, don't do this).

Why essential oils are called essential oils

This is a big point of confusion - and one of the reasons why so many people think essential oils and carrier oils are the same thing (they're not).

Essential oils aren't called 'essential' because they are actually essential for our survival the way essential fatty acids (found in abundance in carrier oils) are. They get their name because they contain 'the essence of the plant'; they are a very concentrated extract of the powerful substances that the herb they're distilled or expressed from holds.

Several essential oils have been shown to boost hair growth. Image by Nayara Dinato.

The actual term 'essential oils' is credited to a guy called Paracelsus von Hohenheim. Back in the days where plant remedies were a part of mainstream medicine, von Hohenheim called the effective component of a medicine (often a herb back then) "the Quintaessential" - hence the name.
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Essential oils are chemically different to carrier oils

Essential oils are extremely complex substances, which contain anywhere from 20-100 different compounds, each at different concentrations. Unlike carrier oils, which are mostly just saturated and unsaturated fatty acids, essential oils can contain alcohols, aldehydes, ethers, ketones, terpenes and several other organic compounds.
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Also unlike carrier oils, which tend to stick to being liquids, essential oils' composition also makes them very volatile, which is why their distinct scents float so easily out of the bottle and can quickly fill a room.

Essential oils can be dangerous if used the wrong way

Using many of these oils straight is a quick way to cause irritation, contact dermatitis, a chemical burn or worse - especially if you're not trained in their use. With few exceptions you should never use an essential oil undiluted.

Overuse or incorrect use of some oils can be extremely dangerous. After all, just because essential oils are natural doesn't mean they're always safe, particularly if you use them against guidelines.
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Always check to see if your oil of choice is appropriate, especially if you are pregnant or suffer from high blood pressure or allergies. 

What's the best essential oil to use for your hair:

There are hundreds of essential oils which have documented benefits for haircare. They include:

Rosemary: Used to fight hair loss, increase growth and decrease scalp irritation

Jujube: used to stimulate hair growth and thicken hair

​Peppermint: Used to stimulate hair growth and calm itchiness

Rosemary. Image by Areumlim.

​What is a carrier oil?

Carrier oils, also called plain oils or base oils, are usually vegetable oils, obtained from the seed of the plant. Their chemical composition is much less complex than essential oils.  As noted above, each oil is  mainly a mixture of saturated and unsaturated fatty acids, without high levels of aromatic compounds - the main ingredient in essential oils. The lack of aromatic compounds is why most carrier oils have the same, plain fatty smell.

How are carrier oils made?

Carrier oils are usually made from the seed or husk of a plant. They can be expeller-pressed - where high pressure is used to remove the oil from the plant without the need for heat. That's how 'virgin' oils are made. Otherwise, they can be distilled using heat.

​Traditionally, most carrier oils are made by boiling the oil-containing plant material until the water evaporates and oil remains. This is the basis of the distillation process used to make commercial carrier oils, too.
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How do you use carrier oils?

Their lack of potent compounds like alcohols, terpenes, or aldehydes means it's safe to use carrier oils undiluted, and it also makes them great for diluting essential oils. In fact, this is why they're called carrier oils; in aromatherapy it's these oils' job to 'carry' the powerful essential oils - by diluting and spreading them - so they can do their work safely, without damaging the skin or causing other injury.
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Carrier oils are also called base oils for pretty much the same reason; they can be used as a base for adding other ingredients that can't be applied in such high concentrations, or that need to be in oil form in order to be used.

Olive oil is one of the most popular carrier oils. Image by Mareefe.

​You can use carrier oils for your hair as is, or mix them with essential oils or macerated oils to create your own custom blend. They can be used as pre-shampoo treatments, scalp oils or simply as a leave in or sealant, to add shine and smoothness to your hair and help lock in moisture. To avoid greasiness, apply a few drops at a time if you plan on leaving your oil in. 
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Are carrier oils safe?

Most carrier oils are categorised as GRAS; generally regarded as safe. Because of this, there isn't a safety limit on how much you can use at one time, unlike with essential oils. Most carrier oils are edible too, as long as they're food grade. Barring contamination, the only major safety risk with these oils comes if you have an allergy to the plant the oil is made from. In that case, it will likely be unsafe for you to use it.

​What's the best carrier oil to use?

There are several carrier oils which are popular for haircare. They include:

Olive oil: This carrier oil is used to add shine and strength to the hair.

Coconut oil: One of the few oils that can penetrate the hair shaft, coconut oil is proven to strengthen hair.
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Castor oil: Used for centuries in African, Asian and Caribbean cultures as a hair growth oil and to darken the hair, castor oil is a great sealing oil, too.

What are macerated oils?

Macerated oils - also called infused oils or oil infusions - are carrier oils infused with one or more herbs. Since they're based on herbs, macerated oils often have similar properties to essential oils extracted from the same parts of the same plants, though they are much less potent.

How are macerated oils made?

Macerated oils are made by taking plant matter (this can be the whole plant, or just the leaves, roots, or petals) and soaking them in a carrier oil, sealing the container and allowing the properties of the plant to infuse into the oil.

​This process happens slowly, over the course of a week or even months. It can also be done very quickly - in a matter of hours - by using a double boiler.

The longer they infuse, the more powerful the macerated oil will be. If you're using a double boiler, you can strengthen the maceration by repeatedly removing used up plant material and replacing it with new material for the oil to absorb.

Macerated oils are made by soaking fresh or dried herbs or flowers in a carrier oil. Image by Silviarita.

​How do you use macerated oils?

Macerated oils can be applied directly to the skin, scalp and hair. You don't need to dilute them, though it's OK to do so if you want to create your own bespoke mixtures.

Macerated oils can make great overnight treatments for hair and scalp. The best way to use them is applied liberally onto your hair, then massaged into your scalp and covered up with plastic wrap and then a headscarf or bonnet to prevent spillages.

Wash it out in the morning for stronger, smoother hair and an energised scalp. If you have an itchy scalp, you can make a macerated oil using herbs that benefit your scalp. Apply a few drops to your scalp and massage in. Don't use too much if you plan on leaving it in as most macerated oils have a strong herbal odour.
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Are macerated oils safe?

Macerated oils are safe as long as the carrier oil they are made with isn't rancid or contaminated, and the herb that they are infused with isn't toxic, spoiled or allergy-inducing. If you have a medical scalp issue, you should be very careful with scalp oils and only use them according to your doctor or trichologist's advice.
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What's the best macerated oil to use for my hair?

Several macerations are popular for their haircare benefits. They include:

Calendula: Typically made by infusing olive oil with marigold flowers, calendula oil is widely used for eczema, dry skin, dry scalp and hair growth.

Rosemary: Rosemary herb, fresh or dried is infused into oil (usually olive). The oil is used for combating hair loss, boosting growth and calming inflammation, rashes and dry, itchy skin.
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Monoi de Tahiti: One of the most famous oil infusions in the world, Monoi de Tahiti is made by steeping gardenia flowers in coconut oil. A traditional Polynesian oil, it has the same international protection as champagne, so authentic Monoi de Tahiti can only come from Tahiti.

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Natural Extracts? It's All In The Ingredients

Can You Use Oil On Protein Sensitive Hair?