The Beginner's Guide to Aromatherapy: What is Aromatherapy (Really!)

Apr 08, 2024

Oftentimes when I am at a social event, I am asked what I do. I am sometimes hesitant to say I am an aromatherapist because reactions can vary – amusement, blank looks, and occasionally interest. But I am an aromatherapist and proud to be one, so I hold my head up high and proclaim I AM AN AROMATHERAPIST!

This often leads to the question, “What is aromatherapy anyway”? What I want to do at that point is to have a 30-minute lesson about aromatherapy, but my hosts would probably be showing me the door at the 15-minute mark, so I bite my tongue and try to explain in a sentence or two. This leaves me deeply unsatisfied because it can’t be easily explained.

I often see aromatherapy defined as the art and science of using essential oils to promote and support health and beauty. It does the trick for a short answer but isn’t accurate.

First of all, although they are the most commonly used aromatics in aromatherapy, essential oils are not the only ones. It boils down to the extraction method, which determines the name of the aromatic. Aromatherapy can mean different things to different people depending on how it is used. So please bear with me while I try to explain the nuances of aromatherapy and aromatics. 

  1. Let’s talk about why essential oils are called “essential.” Most plants contain volatile organic compounds (VOCs) which are responsible for many biological (essential) functions. They are also the “essential” source of essential oils, and other aromatics such as hydrolats, absolutes and CO2 extracts.
    • VOCs are responsible for plant communication. VOCs are classified as semiochemicals when they are used in chemical communication.
    • VOCs play crucial roles in plant ecology and physiology.
      • They can be emitted by plants either continuously or in response to various stimuli such as herbivore attacks, pathogen infection, or environmental stressors. For example, they play a role in plant defence against insects by attracting natural enemies of herbivores (herbivores are insects and animals that consume plant material as a major component of their diet.
      • They can also deter or repel predators, enabling the plant to defend itself against herbivores, pathogens, or competing plants. These VOCs can be toxic or repulsive to insects, birds, and mammals, and will readily vary the number of VOCs in their leaves based on how much sunlight they receive and how much herbivory they are facing.
      • Some VOCs (terpenoids) produced by plants have been identified as having microbial activity which helps protect the plant from fungal attacks and other microbes.
      • They can attract pollinators such as bees, butterflies, and birds to facilitate the reproductive success of the plant. Flowers contain the most VOCs. The maximum scent production occurs when the pollen is ripe, and the flower is ready for pollination. VOCs are more concentrated at the time of day when pollinators are abundant. Odour is important for night-flying insects and other animals where there is little visual stimulus. Bat-pollinated flowers usually have a fruity or cabbage-like scent. Insect-pollinated flowers such as ylang ylang are generally very strongly and sweetly scented. Insects are extremely sensitive to small amounts of VOCs, which means that even if the VOCs can’t be detected by humans, the VOCs' message may still be strong enough to attract insects.
      • VOCs communicate with neighbouring plants to collectively respond to threats, such as herbivory and pathogen attacks.
      • VOCs can also compete with neighbouring plants. For example, plants compete for sunlight, water, and nutrients and, like animals, for territory. Competition, like parasitism, disease, and predation, influences the distribution and the number of organisms in an ecosystem. The interactions of ecosystems define an environment. When organisms compete with one another, they create the potential for resource limitations and possible extinctions. Many chaparral shrubs like sage, rosemary, bay and thyme, are naturally adapted to fire-heavy environments and will grow very close together adding to the possibility of spreading fire which can burn out competition of invading plants and allow for their successful resprouting or reseeding.
      • Some VOCs can enhance a plant’s tolerance to high temperatures and environmental stressors to ensure its survival in harsh conditions.

Based on this information, I hope you can understand how “essential” VOCs are to plants.

  1. What types of aromatics are used in aromatherapy? Essential oils are the most common aromatic used in aromatherapy. All essential oils are extracted from the plant material either by distillation or expression.
    • Steam distillation This method involves passing steam through the plant material, which causes the oil glands containing VOCs to burst open, releasing the volatile compounds. The steam carrying the volatile compounds is then condensed back into liquid form, separating the essential oil from the water. Since essential oils are not water-soluble, they float on top of the condensed water and can be easily collected. Steam distillation is suitable for extracting essential oils from a wide range of plant materials, including flowers, leaves, and seeds, and it's particularly effective for plants with delicate aromatic compounds.
    • Hydrodistillation is like steam distillation except that the plant material is fully immersed in the water. Water distillation is a slow process that favours those essential oils which are not damaged by extensive contact with hot water.
    • Expression, or cold pressing, is an extraction method specifically tailored for extracting essential oils from citrus fruit peels. By avoiding the use of heat, this method helps maintain the integrity of the delicate aromatic compounds present in citrus oils. Expression is especially suitable for obtaining citrus essential oils because it prevents the degradation of the volatile compounds by heat and ensures that the resulting essential oils retain their characteristic aroma and therapeutic properties.
  2. Other methods of extraction include:
    • Solvent Extraction is a very gentle process which tends to create less “rearrangement” of the volatile organic compounds compared with distillation methods. When compared to distillation, solvent-extracted oils tend to have a richer fragrance. In this type of distillation, a pure, volatile solvent is used. In this process not only are the essential oil components of the plant extracted, but also the non-volatile constituents such as waxes and plant dyes. These are referred to as concretes. To produce an absolute, the concrete is gently warmed, and alcohol is mixed in (usually ethanol). During the heating and stirring process, the concrete breaks into minute globules. Since the aromatic molecules are more soluble in alcohol than in the wax the separation of the two is very easy. However, along with the aromatic molecules a certain amount of wax also becomes dissolved, and this is generally removed by agitating and freezing the solution at very low temperatures (about -30 F). The wax then solidifies and separates from the oil. When the wax solidifies and is separated from the oil the result is an absolute which is the most concentrated form of natural fragrance and most closely resembles the plant from which it came. Absolutes can still contain some waxes and pigments along with other constituents from the plant but are mostly comprised of aromatic oil.
    • CO2 Extraction uses liquid carbon dioxide as a solvent on the natural plant matter to dissolve the oil content. CO. Liquid carbon dioxide makes an excellent solvent since the extraction is done at such a low temperature and the process is very fast. Afterwards, the CO2 is brought back to natural pressurization, the CO2 evaporates back into its gaseous state and what is left is the resulting oil. Oils extracted by the CO2 (carbon dioxide) method are commonly called CO2 Extracts. 

Lastly, what is aromatherapy? There is not a black-and-white answer to this question because it depends upon how the aromatics are being used. For example, some just use it for relaxation, others use it strictly for skincare (beauty) and still others use aromatics clinically. Regardless of how the aromatics are being used, they are not always an innocuous substance. It is critical that users, whether hobbyists or seasoned aromatherapists understand that essential oils and other aromatics need to be treated with respect and knowledge. They are not just nice smelly stuff.

Most people who don’t understand aromatherapy use far too much of whatever aromatic they are working with. They may also use them inappropriately e.g., drops of lemon in water. Overall, when essential oils and other aromatics are used correctly, they are safe; however, there are exceptions depending on the oil, the amount used, the person or the condition. Some essential oils and other aromatics can affect allopathic medicine. For example, they can alter the efficacy of certain antibiotics; some chemical constituents found in aromatic extracts can even affect certain chemotherapy drugs. Knowledge is power.

As you can see, aromatherapy and aromatics are complex subjects. Even a 30-minute lesson isn’t long enough to explain why to use aromatherapy, when to use aromatic substances, when not to use any aromatic substances or certain aromatic substances, and how much and how often the aromatic substance should or can be used.

Aromatherapy is a legitimate profession, practised by educated and dedicated practitioners who understand all of the nuances involved to maintain integrity for the profession of aromatherapy. These practitioners are making a difference in people's lives and health. Aromatherapy should not be used in place of allopathic medicine but as a complementary partner to ensure each person receives the best possible care.

Article by: Colleen Thompson, Cert Ed, MIFPA, RA®, EOT®, CA

For over 25 years, Colleen Thompson has been a passionate and highly respected aromatherapy educator. She has owned 3 aromatherapy stores and a holistic spa, and she founded Essence of Thyme in 1995, where she mentors budding aromatherapists from all over the world, helping them create their own thriving aromatherapy businesses.

About Essence of Thyme College of Holistic Studies

Essence of Thyme College of Holistic Studies offers 300- and 630-hour professional aromatherapy certification programs that help you grow a successful, fulfilling career by specializing and creating your market niche. Professional Level Certification prepares graduates to become aromatherapy consultants, launch product lines or retail businesses, or provide services as an adjunct to existing holistic health specializations. Master Level Certification and electives are ideal for certified aromatherapists seeking higher education or a path to clinical aromatherapy practice.

All Essence of Thyme programs focus on aromatherapy product development and advanced formulation, evidence-based research, spa and business management, international industry regulatory guidelines, and sustainability and conservation of essential oil and carrier oil-bearing plants.

Our comprehensive, evidence-based programs meet or exceed the criteria set forth by 5 international professional aromatherapy associations. Learn more about our aromatherapy certification programs.


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