Essential oils are the fragrant oils that are present in many plants. Hundreds of plants yield essential oils that are used as perfumes, food flavorings, medicines, and as fragrant and antiseptic additives in many common products.
Essential oils have been used for thousands of years. The ancient civilizations of Mesopotamia, more than 5,000 years ago, had machines for obtaining essential oils from plants. Essential oils were the primary source of perfumes for the ancient civilizations of Egypt, India, Greece, and Rome. Essential oils have been found in 3,000-year-old tombs in the Pyramids, and early Greek physicians, including Hippocrates, mentioned aromatic plant essences and oil massages for their healing and mood-enhancing qualities. The Romans associated essential oils and their fine aromas with wealth and success. Ayurvedic medicine , the world's oldest healing system, has long recommended essential oil massage as a health treatment for many conditions.
In modern times, essential oils are used in the manufacture of high quality perfumes, as additives in many common products, and in the healing practice of aromatherapy . Aromatherapy was begun in the 1920s by a French chemist named Réné-Maurice Gattefosse, who became convinced of the healing powers of essential oils when he used lavender oil to effectively heal a severe burn on his body. Gattefosse also discovered that essential oils could be absorbed into the bloodstream when applied to the skin, and had medicinal effects inside the body. Another Frenchman, Dr. Jean Valnet, used essential oils during World War II to treat soldiers, and wrote a major book on the topic in 1964 called Aromatherapie. European biochemist, Marguerite Maury, performed thorough studies of how essential oils influence the body and emotions, and popularized essential oil massages as therapy. In the 1990s, aromatherapy was one of the fastest-growing alternative health treatments.
Essential oils are produced using several techniques. Distillation uses water and steam to remove the oils from dried or fresh plants, and the expression method uses machines to squeeze the oil out of plants. Other techniques may use alcohol or solvents to remove essential oils from plant materials.
Essential oils are extremely concentrated. It would take roughly thirty cups of herbal tea to equal the concentration of plant essence in one drop of essential oil. Some essential oils made from rose plants require 4,000 pounds of rose petals to make one pound of essential oil, and are thus very expensive. Lavender is one of the easiest essential oils to produce, because it only takes one hundred pounds of plant material to produce one pound of essential oil. Essential oils are generally very complex chemically, containing many different substances and compounds. Some experts have theorized that essential oils are the lifeblood of a plant, and contain compounds that the plant uses to fight infections and drive away germs and parasites. Scientific research has isolated hundreds of chemicals in essential oils, and has shown many essential oils to have anti-bacterial, anti-fungal, and antiparasitic properties. Some essential oils contain more than 200 identified chemical substances.
Although there are hundreds of essential oils that are used regularly in healing treatments and perfumes, some of the more commonly used essential oils are lavender, chamomile, peppermint, tea tree oil, eucalyptus , geranium, jasmine, rose, lemon, orange, rosemary , frankincense, and sandalwood.
Essential oils are used in several healing systems, including aromatherapy, Ayurvedic medicine, and massage therapy . Essential oils are used for skin and scalp conditions including acne, athlete's foot, burns , cuts, dandruff, eczema , insect bites, parasites, sunburn, warts , and wrinkles. They are recommended for muscle, joint, and circulation problems such as arthritis, high blood pressure, cellulite , aches and pains, and varicose veins . For respiratory problems and infections, various essential oils are prescribed for allergies, asthma, earache , sinus infections, congestion, and colds and flu. Essential oils are also used to improve digestion, promote hormonal balance, and tone the nervous system in conditions including anxiety, depression, sexual dysfunction , and exhaustion.
Essential oils can be used as quick and effective mood enhancers, for increasing energy and alertness or reducing stress and promoting relaxation . Essential oils can be used as perfumes and lotions, and can be used as incense to improve the atmosphere in houses and offices.
In 2002, several reports were made on the benefits of tea tree oil in fighting infections. Although still preliminary, these reports will help pave the way to greater acceptance of essential oils in the mainstream medical community. In the case of tea tree oil, one small study showed its effectiveness in fighting orthopedic (bone, joint, and soft tissue) infections. Another recent study showed promising results for tea tree oil gel in topical treatment of recurrent herpes labialis.
Essential oils work by entering the body in two ways, through the nose and through the skin. The nose is a powerful sense organ, and the sense of smell is connected directly to the limbic system of the brain, which helps control emotions, memory, and several functions in the body. Research has shown that aromas and the sense of smell influence memory recall, moods, and bodily responses such as heart rate, respiration, hormone levels, and stress reactions. Essential oils with their potent aromas can be used to enhance moods, promote relaxation, and increase energy levels.
Essential oils are also absorbed by the skin, and act medicinally once they are absorbed into the body. For instance, eucalyptus oil, long used in common cough and cold remedies, can be rubbed on the chest to break up congestion and mucus inside the lungs. Some essential oils, such as tea tree oil, lavender, and thyme , have natural antiseptics in them, and can be applied to cuts, burns, and sores to disinfect and promote healing.
Because essential oils are very strong and concentrated, they should be diluted with base oils before rubbing them directly on the body. Base oils are gentle and inexpensive oils, and common ones include almond, jojoba, grapeseed, sunflower, and sesame oil . Mineral oil is not recommended as a base oil. Essential oils should be diluted to make up 1–3% of a base oil solution, which is one to three drops of essential oil per teaspoon of base oil. For larger quantities, 20 to 60 drops can be added per 100 milliliters of base oil. Only a few essential oils can be rubbed directly on the skin without dilution. These are lavender, tea tree oil, eucalyptus, and geranium, although people with sensitive skin should use them with care.
Allergic reactions are possible with essential oils. People with sensitive skin or allergies should perform a simple skin test when using essential oils for the first time. To do a skin test, one drop of essential oil can be added to a teaspoon of base oil, and a small amount of this solution can be rubbed on a sensitive spot on the skin, such as the soft side of the arm or behind the ear. If no irritation occurs after 24 hours, then the essential oil is non-allergenic.
Essential oils can be used in a variety of ways. They can be added to massage oils for therapeutic massages. Essential oil solutions can be used on the skin, scalp and hair as lotions, conditioners, and perfumes. A few drops of essential oils can be added to bath water or used in the sauna. Essential oil diffusers, lamps, and candles are available which use heat and steam to spread (diffuse) the aroma of essential oils in rooms. Essential oils can be added to hot-and-cold compresses for injuries and aches. Some essential oils, like tea tree, fennel , and peppermint oil, can be combined with a mixture of water and apple cider vinegar and used as mouthwash. For colds and congestion in the lungs or sinuses, essential oils can be inhaled by adding a few drops to a pot of boiling water, and covering the head with a towel over the pot and breathing the vapors.
Consumers should search for essential oils made by reputable manufacturers. Essential oils should be certified to be 100% pure, without chemical additives or synthetic fragrances. The highest quality oils are generally obtained from distillation and cold pressing methods.
Essential oils should not be taken internally, by mouth, rectum or vagina, unless under medical supervision. Essential oils should be kept away from the eyes. If an essential oil gets into the eyes, they should be rinsed immediately with cold water. Essential oils should be used with care on broken or damaged skin.
Some essential oils have not been thoroughly tested and may be toxic. The oils to be avoided include arnica , bitter almond, calamus, cinnamon, clove, mugwort, sage, wintergreen , and wormwood . Pregnant women should avoid these and basil, fennel, marjoram, myrrh , oregano, star anise , and tarragon. In general, any essential oils that have not been tested or lack adequate information should be avoided.
Some essential oils may cause the skin to become photosensitive, or more sensitive to sunlight and more likely to become sunburned. Essential oils that are photosensitizing include bergamot, orange, lemon, lime, grapefruit, and angelica root. These oils should be avoided before exposure to sunlight and ultraviolet light such as in tanning beds. People with sun-related skin problems should avoid these oils.
Those with health conditions should use care with essential oils. Steam inhalation of essential oils is not recommended for asthma sufferers. The essential oils of rosemary, fennel and sage should be avoided by those with epilepsy .
Pregnant and nursing women should use caution with essential oils, because their skin and bodies are more sensitive and some oils may cause adverse reactions. Essential oils should not be used during the first three months of pregnancy , and after that they should only be used when heavily diluted with base oils. Women with histories of miscarriage should not use essential oils during pregnancy at all. Pregnant women should perform skin tests before using essential oils. Essential oils are not recommended for nursing mothers.
Essential oils should be used with care on children. They are not recommended for children under one year of age, and should be heavily diluted with base oils when used as a skin massage or lotion for children.
Essential oils should be stored out of the reach of children. Clean glass containers are the best storage vessels, and should be dark in color to keep sunlight from damaging the oil. Some essential oils can damage wood, varnish, plastic, and clothing, and should be handled with care.
Most readily available essential oils are safe if used in small doses, and side effects are generally rare. Possible side effects include rashes, itching , and irritation on the skin. Allergic reactions include watery eyes, sneezing , and inflammation. Some essential oils may cause nausea, dizziness , or gastrointestinal discomfort when used in excess or by those with allergic reactions. Some essential oils, particularly those derived from citrus fruit plants, can cause increased sensitivity to sunlight and increased risk of sunburn.
Essential oils are not recommended for those taking homeopathic remedies, as essential oils are believed to interfere with their effectiveness. Essential oils are often blended together to enhance their healing effects, and mixtures can be tailored to individual preferences and conditions. Aromatherapists specialize in creating essential oil blends for individuals and health conditions.
Cooksley, Virginia Gennari. Aromatherapy: A Lifetime Guide to Healing with Essential Oils. Englewood Cliffs, New Jersey: Prentice Hall, 1996.
Lawless, Julia. The Illustrated Encyclopedia of Essential Oils. Rockport, Massachusetts: Element, 1995.
Wildwood, Chrissie. The Encyclopedia of Aromatherapy. Rochester, Vermont: Healing Arts Press, 1996.
Walsh, Nancy. "Tea Tree Oil for Infections." Internal Medicine News (July 1, 2002):16–21.
The Aromatic Thymes. 75 Lakeview Parkway, Barrington, Illinois 60010.
American Alliance of Aromatherapy. P.O. Box 750428, Petaluma, California 94975.
Teresa G. Odle
es·sen·tial oil • n. a natural oil typically obtained by distillation and having the characteristic fragrance of the plant or other source from which it is extracted.