What Is Aromatherapy? Essential Oils, Carrier Oils, Uses and Safety
Aromatherapy is the use of aromatic plant oils through smell and topical application. It is commonly associated with essential oils, but understanding aromatherapy properly also means understanding carrier oils, fragrance notes, dilution, skin and hair applications, and safe handling.
Essential oils are highly concentrated aromatic materials obtained from different parts of plants. Because of their concentration, they are not used in the same way as ordinary vegetable oils. In topical aromatherapy, they are generally incorporated into a suitable carrier or product base before being applied to the skin or scalp.
If you are completely new to the subject, you can also start with our Aromatherapy Learning Hub for related educational resources.
Aromatherapy works with aromatic plant oils for applications involving fragrance, skin care, hair care, relaxation and other personal-care uses.
Essential oils may come from different plant materials such as flowers, leaves, woods, peels and other aromatic parts of plants.
There are two common ways aromatherapy is used:
Through aroma or inhalation
Through topical application in a suitable base
Aromatherapy is therefore much broader than simply adding a pleasant fragrance to a product. The type of essential oil, the carrier used, the intended application and the way the aroma develops can all influence the final experience.
Essential Oils and Carrier Oils Are Not the Same
One of the most important concepts in aromatherapy is understanding the difference between an essential oil and a carrier oil.
Essential oils are highly concentrated aromatic oils.
Carrier oils form the base into which essential oils can be incorporated for topical application. They help distribute the essential oil over a larger area of the skin or scalp.
Examples of carrier oils discussed in aromatherapy include oils such as sunflower, jojoba and argan oil.
The carrier is not simply an inactive addition. It can influence how rich or light a finished product feels, how suitable it is for a particular skin type and even the overall cost of the product.
How Do You Choose a Carrier Oil?
There is no single carrier oil that is automatically right for every aromatherapy product.
The choice depends on several factors, including:
Skin type
Area of application
How light or rich the product should feel
Whether it is intended for the face, body, hair or massage
Product positioning and cost
The overall sensory feel you want to create
For example, lighter carrier oils may be preferred for some facial applications, while richer oils may be more suitable for dry skin, body products or massage applications.
The source and quality of the carrier oil also matter when choosing ingredients for formulation
Understanding Top, Middle and Base Notes
Essential oils do not all behave the same way after application.
Some aromas are immediately noticeable but disappear relatively quickly. Others become noticeable later and remain for a longer period.
This is where the concept of top, middle and base notes becomes useful.
Top Notes
Top notes are usually noticed first.
Citrus aromas such as lemon are examples of fragrances that can create a strong initial impression but fade relatively quickly.
Middle Notes
Middle notes become more noticeable after the initial top notes begin to soften.
Lavender is an example used when explaining a middle note.
Base Notes
Base notes tend to provide a deeper and more lasting aroma.
Sandalwood is an example of a base note.
Understanding these categories helps explain why an aromatic blend may smell different immediately after application compared with several minutes later.
Why Do Lemon and Orange Fragrances Fade Faster?
Citrus aromas such as lemon and orange are commonly associated with top-note behaviour.
They can smell bright and noticeable when a product is first applied, but the fragrance may not remain as long as deeper notes.
This does not necessarily mean something is wrong with the product. It may simply be part of the natural fragrance behaviour of the aromatic material.
When evaluating an aromatherapy blend or fragranced cosmetic product, it is useful to observe how the aroma develops over time rather than judging it only by the first smell.
Can Essential Oils Be Applied Directly to the Skin?
Essential oils are concentrated materials, so using more does not automatically make an aromatherapy product better.
For topical use, essential oils are generally incorporated into a suitable carrier oil or another appropriate cosmetic base.
Direct use of concentrated essential oils can increase the possibility of skin discomfort such as irritation, redness or burning.
This is why dilution and thoughtful product design are important parts of aromatherapy.
Patch testing is also an important consideration when using aromatic products on the skin.
Aromatherapy for Oily and Acne-Prone Skin
Oily skin and acne-prone skin are related concerns, but they are not necessarily the same thing.
A person can have oily skin without having acne, while acne-prone skin requires its own considerations when selecting aromatic ingredients and carrier oils.
For oily skin, the focus is not simply on removing as much oil as possible. Aromatherapy ingredient selection should consider the actual skin concern and the overall product.
Different essential oils may be selected for different purposes. The carrier oil should also be chosen carefully, particularly when designing facial products.
Why Are Some Citrus Essential Oils Better Used at Night?
Certain citrus essential oils require additional consideration when they are used in products applied to the skin.
Lemon, orange and bergamot are discussed in relation to photosensitivity, which is why nighttime application may be preferred for products containing certain citrus essential oils.
This is especially relevant when creating or selecting aromatherapy products intended for facial or other exposed areas of skin.
Essential Oils for Hair and Scalp Care
Aromatherapy is also widely used in hair and scalp products.
The essential oil should be selected according to the specific concern rather than simply choosing an oil because its aroma is appealing.
Hair and scalp concerns discussed in aromatherapy include:
Greasy scalp
Dandruff
Hair fall and hair-growth support
Dry or damaged hair
General scalp care
Essential oils such as rosemary, tea tree, eucalyptus, cedarwood and patchouli may be considered in different hair and scalp contexts.
Carrier oils such as jojoba and argan can also form part of hair and scalp applications depending on the intended product.
Aromatherapy for Dandruff
Dandruff is one of the scalp concerns commonly discussed in aromatherapy. Essential oils such as tea tree, eucalyptus and other aromatic oils may be considered depending on the scalp concern and the type of product being created.
The essential oil is only one part of the formulation. The carrier or product base and the way the product is intended to be used on the scalp are also important considerations.
Aromatherapy for Hair Loss
Aromatherapy is also used in hair and scalp routines intended to support concerns related to hair fall and the scalp environment.
Essential oils such as rosemary are commonly discussed in this context, while the choice of carrier oil and the overall hair-care product also influence how the aromatherapy application is used.
Understanding the specific hair or scalp concern helps in selecting oils more thoughtfully rather than choosing an essential oil only because of its fragrance.
Learn Aromatherapy in More Detail
These guides are designed to help you understand individual aromatherapy concepts one topic at a time, from essential oils and carrier oils to fragrance notes, skin applications, hair care and storage.