Essential oils are the oldest and some of the most powerful therapeutic agents know to man. They have a millennium-long history of use in healing and in religious ceremony throughout the ancient world, besides their use as fragrance.
They were used to cure every ailment. Such as clove and lemon, were highly valued as antiseptics hundreds of years before the discovery of modern antiseptics.
Aromatics, as they were called, were some of the most prized treasures of the ancient world - they were traded for gold, silver, and even slaves.
It appears that the ancient Egyptians were the first to recognize the therapeutic potential of essential oils. They created fragrances for personal use as well as for ritualistic and ceremonial use in the temples and pyramids. Many mixtures were composed of myrrh oil and honey. Myrrh was most often used for embalming, due to its effectiveness in preventing bacterial growth.
The physicians of Greece came to Egypt to learn about the oils. The Romans used essential oils by diffusing them in their temples and political buildings. They were fond of soaking in oil-scented baths, then receiving a fragrant oil massage.
The ancient Arabian people began to study the chemical properties of essential oils. They developed and refined the distillation process. Europeans began producing essential oils in the 12th century. When the great library was burned in Alexandria during the Dark Ages, much of the knowledge of essential oils and their uses was lost. It was only through the cosmetic and perfume industry that some of the valuable science of aromatherapy began to resurface.
The modern rediscovery of the value of essential oils is attributed to French cosmetic chemist, Ren?-Maurice Gattefoss?, Ph.D. In July of 1910, a lab explosion set him aflame. After extinguishing the flames, he discovered that his hands were quickly developing gas gangrene. But just one rinse with lavender essential oil stopped the horrible process. Healing began the next day. His discovery was quite accidental -- he had plunged his arm into a vessel that he assumed was water. But it actually contained pure lavender oil (Lavendula officinalis). With regular application of lavender oil, the wound healed without a scar. When he investigated the chemistry of the oil, he discovered that some of its chemical components had tremendous healing properties. This incident prompted Dr. Gattefoss? to research the healing compounds of essential oils. His research spurred the clinical use of essential oils.
As a result, French physician, Dr. Jean Valnet, used therapeutic-grade essential oils on patients suffering battlefield injuries during World War II. He was able to save the lives of many soldiers who might otherwise have died, even with antibiotics. After the war, he documented his clinical results in his book, The Practice of Aromatherapy. He also shared his knowledge with his student, Daniel P?no?l, M.D., who later co-authored the first definitive medical textbook on the chemistry and clinical application of essential oils: L'aromath?rapie exactement.
What Are Essential Oils?
Essential oils are highly concentrated natural plant extracts; a drop or two can produce significant results. An entire plant, when distilled, might produce only a single drop of essential oil. That is why their potency is far greater than dried herbs. Pressing or distillation extracts the subtle, volatile liquids (meaning they evaporate quickly) from plants, shrubs, flowers, trees, roots, bushes, and seeds, that make up essential oils.
Essential oils are the life-blood of the plant, protecting it from bacterial and viral infections, cleansing breaks in its tissue and delivering oxygen and nutrients into the cells. In essence, they act as the immune system of the plant. That is why they are so essential to the plant -- without them, plants could not survive.
In the human body, they have a similar action -- such as transporting valuable nutrients to the cells; increasing oxygen intake, and digesting toxic waste in the blood. This is because the three primary elements - carbon, hydrogen and oxygen-are common to both human beings and essential oils. This shared chemistry makes essential oils one of the most compatible of all plant substances with human biochemistry.
Not only that, but the lipid-soluble structure of essential oils and the fact that they have a protein-like structure similar to human cells and tissues makes them even more compatible with human tissue.
Essential oils are very different from vegetable oils (also called fatty oils), such as corn oil, olive oil, peanut oil, etc. Fatty oils are produced by pressing nuts or seeds. They are quite greasy, are not antimicrobial nor help transport oxygen, and will go rancid over time. Essential oils, however, are not greasy nor do they clog the pores like vegetable oils can.
Essential oils are highly complex substances. They are mosaics of hundreds - even thousands - of different natural chemicals. The average essential oil may contain anywhere from 80 to 400 known chemical constituents. Many oils contain even more, occurring in minute quantities - but all contributing to the oil's therapeutic effects. It requires years of study to understand these constituents, their activity and functions.
Different varieties of the same oil can have widely different therapeutic actions, depending on their chemistry. For example, basil high in linalool or fenchol is primarily used for its antiseptic properties. However, basil high in methyl chavicol is more anti-inflammatory than antiseptic. A third type, basil high in eugenol, has both anti-inflammatory and antiseptic effects.
In addition, essential oils can be processed in different ways, which dramatically effects their chemistry and medicinal action. Oils that have been redistilled two or three times are obviously not as potent as oils that have been distilled only once. Also, oils that are subjected to high heat and pressure in processing have an inferior profile of chemical constituents, since excessive heat and temperature fractures and breaks down many of the delicate aromatic compounds within the oil -- compounds that are responsible for much of the therapeutic action of the oil.
Of even greater importance is the fact that some oils are thinned or cut (i.e. adulterated) with synthetic chemicals.
1. Absolutes vs. Concretes
Absolutes are "essences," rather than "essential" oils. They are generally obtained from the extraction of a concrete with alcohol. A concrete is the solid waxy residue derived from hexane extraction of plant material (usually the flower petals). This method of extraction is used for botanicals where the fragrance and therapeutic parts of the plant can only be unlocked using solvents. These are not to be used internally, as traces of petrochemicals remain in the oil. Jasmine and neroli are examples of absolutes.
Expressed oils are pressed from the rind of fruits (usually citrus). Tangerines, grapefruits, lemons and oranges are produced by this method. Technically speaking, these are not "essential oils" - they are expressed oils, but they are highly regarded for their therapeutic properties, none the less. It is best to use only organically grown crops for this method, since pesticide residues, especially highly toxic, oil-soluble carbamate and chloride-based petrochemicals, can become highly concentrated in the oil.
3. Solvent Extraction
Solvent extration involves the use of oil-soluble solvents, such as hexane, dimethylenechloride, and acetone. There is no guarantee that the finished product will be free of solvent residues.
Steam distillation is the oldest and most traditional method of extraction. Plant material is inserted into a cooking chamber, and steam is passed through it. After the steam is collected and condensed, it is processed through a separator to collect the oil. The amount of pressure used, the amount of time the plant material is steamed and the material the steam chamber is constructed of contribute a great deal to the quality of the oil (or lack of).
Historically, there have been three models for using essential oils: the French, the German, and the English methods.
The English traditionally dilute a small amount of essential oil in vegetable oil and massage the body to relax and relieve stress.
The French prefer to ingest (swallow) therapeutic-grade essential oils. Many French practitioners have found that taking the oils internally is highly effective.
The Germans recommend inhalation of the essential oils. There is good reason for this - research has shown that these aromatic compounds can exert strong effects on the brain, especially on the hypothalamus (the hormone command center of the body) and the limbic system (the seat of emotions).
The best method of application depends on the need. In some cases, inhalation might be preferred over topical application if the goal is to induce weight loss or balance mood and emotions. In other cases, topical application would produce better results, as in the case of muscle or spinal injuries. For indigestion, peppermint oil taken orally is very effective. Yet peppermint can also produce the same results when massaged on the stomach. In some cases, all three methods of application (topical, inhalation and ingestion) are interchangeable and may produce similar benefits.
The two most common methods of essential oil application are cold-air diffusing and neat (undiluted) topical application. Healing response is greatly enhanced when essential oils are incorporating into the disciplines of reflexology, Vita Flex, acupressure, acupuncture, auricular techniques, lymphatic massage, spinal touch, and the Raindrop Technique.
The Fragrance Factor
Aromatherapy means to treat with aroma through inhalation (although it also encompasses the topical application of essential oils). Research has shown that we respond to aroma within one to three seconds. Scientists are just beginning to explore how aroma reaches and influences the human brain, emotions and body.
An oil's fragrance is created when vapor evaporates from it. The heavier the molecular weight of the oil, the less volatile it is (the less it will evaporate). Oils with lighter molecular weights, evaporate or 'flash off' quickly. Therefore, the scents of lavender or geranium last only about 20 minutes. Heavier oils such as myrrh, frankincense, sandalwood, and patchouly evaporate slower, and therefore, their scent lasts longer.
As the molecules in a fragrance evaporate into the air and are inhaled, olfactory membranes (protected by the mucous lining of the nose) capture them. These membranes are lined with receptor cells that can be considered hair-like extensions of nerve fibers. Each fragrance molecule fits itself into specific receptor cells, like a puzzle piece. The stimulation by odor molecules causes the receptors to trigger electrical impulses to different parts of the brain. These nerve impulses are transmitted to the limbic system of the brain. The brain then sends more impulses to different parts of the body, depending on type and function.
The limbic system is directly connected to the parts of the brain that control heart rate, blood pressure, breathing, memory, stress levels, and hormone balance. Because of this, essential oils can have profound physiological and psychological effects.
Have you ever noticed that a scent or fragrance can instantly evoke a memory or an emotion on an unconscious level? This is because the sense of smell is the only one of the five senses that is directly linked to the limbic lobe of the brain - the emotional control center. Emotions such as anxiety, depression, fear, anger, as well as joy all emanate from this region.
The limbic lobe can also directly activate the hypothalamus - the "master gland." The hypothalamus functions as the hormonal control center of the body. It releases chemical messengers that affect the production of growth hormones, sex hormones, thyroid hormones, and neurotransmitters.
Essential oils, through their fragrance and molecular structure, can directly stimulate both the limbic lobe and the hypothalamus. In this way, essential oils can exert a profound effect on the body and the mind.