A diffuser and a bottle of essential oil
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Aromatherapy is a pseudoscience based on the usage of aromatic materials, including essential oils, and other aroma compounds, with claims for improving psychological or physical well-being. It is offered as a complementary therapy or as a form of alternative medicine, the first meaning alongside standard treatments, the second instead of conventional, evidence-based treatments.
Aromatherapists, people who specialize in the practice of aromatherapy, utilize blends of supposedly therapeutic essential oils that can be used as topical application, massage, inhalation or water immersion. There is no good medical evidence that aromatherapy can either prevent, treat, or cure any disease. Placebo-controlled trials are difficult to design, as the point of aromatherapy is the smell of the products. There is disputed evidence that it may be effective in combating postoperative nausea and vomiting.
The use of essential oils for therapeutic, spiritual, hygienic and ritualistic purposes goes back to ancient civilizations including the Chinese, Indians, Egyptians, Greeks, and Romans who used them in cosmetics, perfumes and drugs. Oils were used for aesthetic pleasure and in the beauty industry. It was a luxury item and a means of payment. It was believed the essential oils increased the shelf life of wine and improved the taste of food.
Oils are described by Dioscorides, along with beliefs of the time regarding their healing properties, in his De Materia Medica, written in the first century. Distilled essential oils have been employed as medicines since the eleventh century, when Avicenna isolated essential oils using steam distillation.
In the era of modern medicine, the naming of this treatment first appeared in print in 1937 in a French book on the subject: Aromathérapie: Les Huiles Essentielles, Hormones Végétales by René-Maurice Gattefossé, a chemist. An English version was published in 1993. In 1910, Gattefossé burned a hand very badly and later claimed he treated it effectively with lavender oil.
Choice and purchase
Oils with standardized content of components (marked FCC, for Food Chemicals Codex) are required[by whom?] to contain a specified amount of certain aroma chemicals that normally occur in the oil. There is no law that the chemicals cannot be added in synthetic form to meet the criteria established by the FCC for that oil. For instance, "lemongrass essential oil must contain 75% aldehyde to meet the FCC profile for that oil, but that aldehyde can come from a chemical refinery instead of from lemongrass."  To say that FCC oils are "food grade" makes them seem natural when they are not necessarily so.
Undiluted essential oils suitable for aromatherapy are termed 'therapeutic grade', but there are no established and agreed standards for this category.
Analysis using gas chromatography (GC) and mass spectrometry (MS) establishes the quality of essential oils. These techniques are able to measure the levels of components to a few parts per billion. This does not make it possible to determine whether each component is natural or whether a poor oil has been 'improved' by the addition of synthetic aromachemicals, but the latter is often signaled by the minor impurities present. For example, linalool made in plants will be accompanied by a small amount of hydro-linalool, whilst synthetic linalool has traces of dihydro-linalool.
There is no good medical evidence that aromatherapy can prevent or cure any disease. For cancer patients, aromatherapy has been found to lower anxiety and depression symptoms. In 2015, the Australian Government's Department of Health published the results of a review of alternative therapies that sought to determine if any were suitable for being covered by health insurance; aromatherapy was one of 17 therapies evaluated for which no clear evidence of effectiveness was found.
Evidence for the efficacy of aromatherapy in treating medical conditions is poor, with a particular lack of studies employing rigorous methodology. A number of systematic reviews have studied the clinical effectiveness of aromatherapy in respect to pain management in labor, the treatment of post-operative nausea and vomiting, managing challenging behaviors in people who have dementia, and symptom relief in cancer. However, some studies have come to the conclusion that while it does improve the patient's mood, there is no conclusive evidence on how it works with pain management. Studies have been inconclusive because of the fact that no straightforward evidence exists. All of these reviews report a lack of evidence on the effectiveness of aromatherapy.
There is an immense amount of studies exploring the concerns that essential oils are highly concentrated and can irritate the skin when used in undiluted form. Therefore, they are normally diluted with a carrier oil for topical application, such as jojoba oil, olive oil, or coconut oil. Phototoxic reactions may occur with citrus peel oils such as lemon or lime. Also, many essential oils have chemical components that are sensitisers (meaning that they will, after a number of uses, cause reactions on the skin, and more so in the rest of the body). Chemical composition of essential oils could be affected by herbicides if the original plants are cultivated versus wild-harvested. Some oils can be toxic to some domestic animals, with cats being particularly prone.
Most oils can be toxic to humans as well. A report of three cases documented gynecomastia in prepubertal boys who were exposed to topical lavender and tea tree oils. The Aromatherapy Trade Council of the UK issued a rebuttal. The Australian Tea Tree Association, a group that promotes the interests of Australian tea tree oil producers, exporters and manufacturers issued a letter that questioned the study and called on the New England Journal of Medicine for a retraction. Another article published by a different research group also documented three cases of gynecomastia in prepubertal boys who were exposed to topical lavender oil.
While some advocate the ingestion of essential oils for therapeutic purposes, licensed aromatherapy professionals do not recommend self-prescription due to the highly toxic nature of some essential oils. Some very common oils like eucalyptus are extremely toxic when taken internally. Doses as low as 2 mL have been reported to cause clinically significant symptoms and severe poisoning can occur after ingestion of as little as 4 mL. A few reported cases of toxic reactions like liver damage and seizures have occurred after ingestion of sage, hyssop, thuja and cedar oils. Accidental ingestion may happen when oils are not kept out of reach of children. As with any bioactive substance, an essential oil that may be safe for the general public could still pose hazards for pregnant and lactating women.
Oils both ingested and applied to the skin can potentially have negative interactions with conventional medicine. For example, the topical use of methyl salicylate-heavy oils like wintergreen may cause bleeding in users taking the anticoagulant warfarin.
- "Aromatherapy". Better Health Channel. Archived from the original on 27 February 2012. Retrieved 14 August 2014.
- Kuriyama, Hiroko; Watanabe, Satoko; Nakaya, Takaaki; Shigemori, Ichiro; Kita, Masakazu; Yoshida, Noriko; Masaki, Daiki; Tadai, Toshiaki; Ozasa, Kotaro; Fukui, Kenji; Imanishi, Jiro (2005). "Immunological and Psychological Benefits of Aromatherapy Massage". Evidence-Based Complementary and Alternative Medicine. 2 (2): 179–184. doi:10.1093/ecam/neh087. PMC 1142199. PMID 15937558.
- "Alternative therapies and cancer - Cancer Information". Macmillan Cancer Support. 17 April 2014. Archived from the original on 3 October 2014. Retrieved 21 August 2019.
- Lee, Myeong Soo; Choi, Jiae; Posadzki, Paul; Ernst, Edzard (March 2012). "Aromatherapy for health care: An overview of systematic reviews". Maturitas. 71 (3): 257–260. doi:10.1016/j.maturitas.2011.12.018. PMID 22285469.
- Ades TB, ed. (2009). "Aromatherapy". American Cancer Society Complete Guide to Complementary and Alternative Cancer Therapies (2nd ed.). American Cancer Society. pp. 57–60. ISBN 978-0-944235-71-3.
- Hines S, Steels E, Chang A, Gibbons K (March 2018). "Aromatherapy for treatment of postoperative nausea and vomiting". Cochrane Database Syst Rev. 3: CD007598. doi:10.1002/14651858.CD007598.pub3. PMC 6494172. PMID 29523018.
- "University of Maryland Medical Center - Aromatherapy". University of Maryland Medical Center. University of Maryland Medical Center. Retrieved 13 August 2014.
- Dioscorides, Pedanius; Goodyer, John (trans.) (1959). Gunther, R.T. (ed.). The Greek Herbal of Dioscorides. New York: Hafner Publishing. OCLC 3570794.[page needed]
- Forbes, R.J. (1970). A short history of the art of distillation. Leiden: E.J. Brill. OCLC 2559231.[page needed]
- Ericksen, Marlene (2000). Healing With Aromatherapy. New York: McGraw-Hill. p. 9. ISBN 0-658-00382-8.
- Gattefossé, R.-M.; Tisserand, R. (1993). Gattefossé's aromatherapy. Saffron Walden: C.W. Daniel. ISBN 0-85207-236-8.[page needed]
- "Aromatherapy". University of Maryland Medical Center. Retrieved 24 October 2010.
- Valnet, J.; Tisserand, R. (1990). The practice of aromatherapy: A classic compendium of plant medicines & their healing properties. Rochester, VT: Healing Arts Press. ISBN 0-89281-398-9.[page needed]
- Fadul, Jose (2014). Encyclopedia of Theory and Practice in Psychotherapy and Counseling. Lulu Press Inc. p. 48. ISBN 978-1-312-34920-9. Retrieved 27 November 2019.
- Adams, Robert P. (2007). Identification of Essential Oil Components by Gas Chromatography/Mass Spectrometry.
- Barrett, S. "Aromatherapy: Making Dollars out of Scents". Science & Pseudoscience Review in Mental Health. Scientific Review of Mental Health Practice. Retrieved 21 February 2013.
- PDQ. "Aromatherapy With Essential Oils". National Cancer Institute. National Cancer Institute.
- Baggoley C (2015). "Review of the Australian Government Rebate on Natural Therapies for Private Health Insurance" (PDF). Australian Government – Department of Health. Archived from the original (PDF) on 26 June 2016. Retrieved 12 December 2015. Lay summary – Gavura, S. Australian review finds no benefit to 17 natural therapies. Science-Based Medicine (19 November 2015).
- van der Watt, G; Janca, A (2008). "Aromatherapy in nursing and mental health care". Contemporary Nurse. 30 (1): 69–75. doi:10.5172/conu.6184.108.40.206. PMID 19072192.[permanent dead link]
- Edris, AE (2007). "Pharmaceutical and therapeutic Potentials of essential oils and their individual volatile constituents: A review". Phytotherapy Research. 21 (4): 308–323. doi:10.1002/ptr.2072. PMID 17199238.
- Smith CA, Collins CT, Crowther CA (2011). "Aromatherapy for pain management in labour". Cochrane Database Syst Rev (7): CD009215. doi:10.1002/14651858.CD009215. PMID 21735438.
- Forrester LT, Maayan N, Orrell M, Spector AE, Buchan LD, Soares-Weiser K (February 2014). "Aromatherapy for dementia". Cochrane Database Syst Rev (2): CD003150. doi:10.1002/14651858.CD003150.pub2. PMID 24569873.
- Shin ES, Seo KH, Lee SH, Jang JE, Jung YM, Kim MJ, Yeon JY (2016). "Massage with or without aromatherapy for symptom relief in people with cancer". Cochrane Database Syst Rev (6): CD009873. doi:10.1002/14651858.CD009873.pub3. PMID 27258432.
- Lakhan, Sheafer, Tepper, Shaheen, Heather, Deborah (2016). "The Effectiveness of Aromatherapy in Reducing Pain: A Systematic Review and Meta-Analysis". Pain Research and Treatment. 2016: 13.CS1 maint: multiple names: authors list (link)
- Posadzki P, Alotaibi A, Ernst E (2012). "Adverse effects of aromatherapy: a systematic review of case reports and case series". Int J Risk Saf Med. 24 (3): 147–161. doi:10.3233/JRS-2012-0568. PMID 22936057.
- Manion, Widder, Chelsea, Rebecca (May 2017). "Essentials of essential oils". American Journal of Health-System Pharmacy. 74 (9).
- Grassman, J; Elstner, E F (1973). "Essential Oils". In Caballero, Benjamin; Trugo, Luiz C; Finglas, Paul M (eds.). Encyclopedia of Food Sciences and Nutrition (2nd ed.). Academic Press. ISBN 0-12-227055-X.[page needed]
- Cather, JC; MacKnet, MR; Menter, MA (2000). "Hyperpigmented macules and streaks". Proceedings. Baylor University Medical Center. 13 (4): 405–406. doi:10.1080/08998280.2000.11927714. PMC 1312240. PMID 16389350.
- Edwards, J; Bienvenu, FE (1999). "Investigations into the use of flame and the herbicide, paraquat, to control peppermint rust in north-east Victoria, Australia". Australasian Plant Pathology. 28 (3): 212. doi:10.1071/AP99036.
- Adamovic, DS. "Variability of herbicide efficiency and their effect upon yield and quality of peppermint (Mentha X Piperital L.)". Retrieved 6 June 2009.
- Bischoff, K; Guale, F (1998). "Australian Tea Tree (Melaleuca Alternifolia) Oil Poisoning in Three Purebred Cats". Journal of Veterinary Diagnostic Investigation. 10 (2): 208–210. doi:10.1177/104063879801000223. PMID 9576358.
- American College of Healthcare Sciences. "Essential Oil". American College of Healthcare Sciences. Accredited Online Holistic Health College. Retrieved 13 April 2019.
- Henley DV, Lipson N, Korach KS, Bloch CA (2007). "Prepubertal gynecomastia linked to lavender and tea tree oils". N. Engl. J. Med. 356 (5): 479–485. doi:10.1056/NEJMoa064725. PMID 17267908.
- "Lavender & Tea Tree Oil Rebuttle(sic)".
- 'ATTIA refutes gynecomastia link', Article Date: 21 February 2007
- Diaz A, Luque L, Badar Z, Kornic S, Danon M (2016). "Prepubertal gynecomastia and chronic lavender exposure: report of three cases". J. Pediatr. Endocrinol. Metab. 29 (1): 103–107. doi:10.1515/jpem-2015-0248. PMID 26353172.
- "Eucalyptus oil". International Programme on Chemical Safety (UPCS).
- Millet, Y; Jouglard, J; Steinmetz, MD; Tognetti, P; Joanny, P; Arditti, J (1981). "Toxicity of Some Essential Plant Oils. Clinical and Experimental Study". Clinical Toxicology. 18 (12): 1485–1498. doi:10.3109/15563658108990357. PMID 7333081.
- Wilson, Debra Rose. "About Wintergreen Essential Oil". www.healthline.com. Healthline Media.