Aromatherapy

Aromatherapy
A diffuser and a bottle of essential oil.
Alternative therapy
Benefits	Placebo
MeSH	D019341

Aromatherapy uses plant materials and aromatic plant oils, including essential oils, and other aroma compounds for the purpose of altering one's mood, cognitive, psychological or physical well-being.^[1]

It can be offered as a complementary therapy or, more controversially, as form of alternative medicine. Complementary therapy can be offered alongside standard treatment,^[2] with alternative medicine offered instead of conventional, evidence-based treatments.^[3]

Aromatherapists, who specialize in the practice of aromatherapy, utilize blends of therapeutic essential oils that can be issued through topical application, massage, inhalation or water immersion to stimulate a desired response.

There is no good medical evidence that aromatherapy can either prevent or cure any disease, but it might help improve general well-being.^[4]

History

The use of essential oils for therapeutic, spiritual, hygienic and ritualistic purposes goes back to a number of ancient civilizations including the Chinese, Indians, Egyptians, Greeks, and Romans who used them in cosmetics, perfumes and drugs.^[5]

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.^[6] Distilled essential oils have been employed as medicines since the invention of distillation in the eleventh century,^[7] when Avicenna isolated essential oils using steam distillation.^[8]

The concept of aromatherapy was first mooted by a small number of European scientists and doctors, in about 1907. In 1937, the word first appeared in print 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.^[9] In 1910, Gattefossé burned a hand very badly and later claimed he treated it effectively with lavender oil.^[10]

A French surgeon, Jean Valnet, pioneered the medicinal uses of essential oils, which he used as antiseptics in the treatment of wounded soldiers during World War II.^[11]

Modes of application

The modes of application of aromatherapy include:

• Aerial diffusion: for environmental fragrancing or aerial disinfection
• Direct inhalation: for respiratory disinfection, decongestant, expectoration as well as psychological effects
• Topical applications: for general massage, baths, compresses, therapeutic skin care^[12]

Materials

Some of the materials employed include:

• Essential oils: fragrant oils extracted from plants chiefly through steam distillation (e.g., eucalyptus oil) or expression (grapefruit oil). However, the term is also occasionally used to describe fragrant oils extracted from plant material by any solvent extraction. This material includes incense reed diffusers.
• Absolutes: fragrant oils extracted primarily from flowers or delicate plant tissues through solvent or supercritical fluid extraction (e.g., rose absolute). The term is also used to describe oils extracted from fragrant butters, concretes, and enfleurage pommades using ethanol.
• Carrier oils: typically oily plant base triacylglycerides that dilute essential oils for use on the skin (e.g., sweet almond oil).
• Herbal distillates or hydrosols: the aqueous by-products of the distillation process (e.g., rosewater). Common herbal distillates are chamomile, rose, and lemon balm.
• Infusions: aqueous extracts of various plant material (e.g., infusion of chamomile).
• Phytoncides: various volatile organic compounds from plants that kill microbes. Many terpene-based fragrant oils and sulfuric compounds from plants in the genus "Allium" are phytoncides, though the latter are likely less commonly used in aromatherapy due to their disagreeable odors.
• Aroma lamp or diffuser: an electric or candle-fueled device which volatilizes essential oils, usually mixed with water.
• Vaporizer: typically higher oil content plant based materials dried, crushed, and heated to extract and inhale the aromatic oil vapors in a direct inhalation modality.

Theory

Aromatherapy is the treatment or prevention of disease by use of essential oils. Other stated uses include pain and anxiety reduction, enhancement of energy and short-term memory, relaxation, hair loss prevention, and reduction of eczema-induced itching.^[13][14]

Two basic mechanisms are offered to explain the purported effects. One is the influence of aroma on the brain, especially the limbic system through the olfactory system.^[15] The other is the direct pharmacological effects of the essential oils.^[16]

In the English-speaking world, practitioners tend to emphasize the use of oils in massage. Aromatherapy tends to be regarded as a pseudoscientific fraud at worst.^[17]

Choice and purchase

Oils with standardized content of components (marked FCC, for Food Chemicals Codex) are required 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 liquid chromatography (GLC) 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.

Effectiveness

There is some evidence that aromatherapy can help improve general well-being, but no good medical evidence that it can prevent or cure disease.^[4]

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.^[18] Evidence for the efficacy of aromatherapy in treating medical conditions is poor, with a particular lack of studies employing rigorous methodology.^[19][20]

Safety concerns

Aromatherapy carries a risk of a number of adverse effects and this consideration, combined with the lack of evidence of its therapeutic benefit, makes the practice of questionable worth.^[21]

Because essential oils are highly concentrated they can irritate the skin when used in undiluted form.^[22] 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.^[23] 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). Some of the chemical allergies could even be caused by pesticides, if the original plants are cultivated.^[24][25] Some oils can be toxic to some domestic animals, with cats being particularly prone.^[26][27]

A child hormone specialist at the University of Cambridge claimed "... these oils can mimic estrogens" and "people should be a little bit careful about using these products."^[28] The Aromatherapy Trade Council of the UK has issued a rebuttal.^[29] 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.^[30] The New England Journal of Medicine has so far not replied and has not retracted the study.

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.

While some advocate the ingestion of essential oils for therapeutic purposes, licensed aromatherapy professionals do not recommend self-prescription due the highly toxic nature of some essential oils. Some very common oils like eucalyptus are extremely toxic when taken internally. Doses as low as one teaspoon have been reported to cause clinically significant symptoms and severe poisoning can occur after ingestion of 4 to 5 ml.^[31] A few reported cases of toxic reactions like liver damage and seizures have occurred after ingestion of sage, hyssop, thuja, and cedar.^[32] Accidental ingestion may happen when oils are not kept out of reach of children.

Oils both ingested and applied to the skin can potentially have negative interactions with conventional medicine. For example, the topical use of methylsalicylate-heavy oils like sweet birch and wintergreen may cause hemorrhaging in users taking the anticoagulant warfarin.

Adulterated oils may also pose problems depending on the type of substance used.

See also

• Aromachologist
• List of unproven and disproven cancer treatments

References

1. "Aromatherapy". Better Health Channel. Retrieved 2014-08-14.
2. http://www.hindawi.com/journals/ecam/2005/270901/abs/
3. "What are complementary and alternative therapies?".
4. 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 9780944235713.
5. "University of Maryland Medical Center - Aromatherapy". University of Maryland Medical Center. University of Maryland Medical Center. Retrieved 13 August 2014.
6. Dioscorides, Pedanius; Goodyer, John (trans.) (1959). Gunther, R.T., ed. The Greek Herbal of Dioscorides. New York: Hafner Publishing. OCLC 3570794.
7. Forbes, R.J. (1970). A short history of the art of distillation. Leiden: E.J. Brill. OCLC 2559231.
8. Ericksen, Marlene (2000). Healing With Aromatherapy. New York: McGraw-Hill. p. 9. ISBN 0-658-00382-8.
9. Gattefossé, R.-M.; Tisserand, R. (1993). Gattefossé's aromatherapy. Saffron Walden: C.W. Daniel. ISBN 0-85207-236-8.
10. "Aromatherapy". University of Maryland Medical Center. Retrieved 24 October 2010.
11. 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.
12. "Organic Bath Oil". Plaisirs. Retrieved 11 October 2011.
13. Kingston, Jennifer A. (28 July 2010). "Nostrums: Aromatherapy Rarely Stands Up to Testing". The New York Times. Retrieved 29 December 2010.
14. Nagourney, Eric (11 March 2008). "Skin Deep: In Competition for your Nose". The New York Times. Retrieved 29 December 2010.
15. Mathrani, Vandana (17 January 2008). "The Power of Smell".
16. Prabuseenivasan, Seenivasan; Jayakumar, Manickkam; Ignacimuthu, Savarimuthu (2006). "In vitro antibacterial activity of some plant essential oils". BMC Complementary and Alternative Medicine. 6: 39. doi:10.1186/1472-6882-6-39. PMC 1693916. PMID 17134518.
17. Barrett, Stephen. "Aromatherapy: Making Dollars out of Scents". Science & Pseudoscience Review in Mental Health. Scientific Review of Mental Health Practice. Retrieved 21 February 2013.
18. Baggoley C (2015). "Review of the Australian Government Rebate on Natural Therapies for Private Health Insurance" (PDF). Australian Government – Department of Health. Lay summary – Gavura, S. Australian review finds no benefit to 17 natural therapies. Science-Based Medicine. (19 November 2015).
19. van der Watt, Gillian; Janca, Aleksandar (August 2008). "Aromatherapy in nursing and mental health care". Contemporary Nurse. 30 (1): 69–75. doi:10.5555/conu.673.30.1.69 (inactive 2015-01-09). PMID 19072192.
20. Edris, Amr E. (2007). "Pharmaceutical and therapeutic Potentials of essential oils and their individual volatile constituents: A review". Phytotherapy Research. 21 (4): 308–23. doi:10.1002/ptr.2072. PMID 17199238.
21. Posadzki P, Alotaibi A, Ernst E (January 2012). "Adverse effects of aromatherapy: a systematic review of case reports and case series". Int J Risk Saf Med (Systematic review). 24 (3): 147–61. doi:10.3233/JRS-2012-0568. PMID 22936057.
22. Grassman, J; Elstner, E F (1973). "Essential Oils". In Caballero, Benjamin; Trugo, Luiz C; Finglas, Paul M. Encyclopedia of Food Sciences and Nutrition (2nd ed.). Academic Press. ISBN 0-12-227055-X.
23. Cather, JC; MacKnet, MR; Menter, MA (2000). "Hyperpigmented macules and streaks". Proceedings. Baylor University Medical Center. 13 (4): 405–6. PMC 1312240. PMID 16389350.
24. Edwards, J.; Bienvenu, F.E. (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.
25. Adamovic, D.S.; et al. "Variability of herbicide efficiency and their effect upon yield and quality of peppermint (Mentha X Piperital L.)". Retrieved 6 June 2009.
26. The Lavender Cat – Cats and Essential Oil Safety
27. Bischoff, K.; Guale, F. (1998). "Australian Tea Tree (Melaleuca Alternifolia) Oil Poisoning in Three Purebred Cats". Journal of Veterinary Diagnostic Investigation. 10 (2): 208–10. doi:10.1177/104063879801000223. PMID 9576358.
28. "Oils make male breasts develop". BBC News. London. 1 February 2007. Archived from the original on 29 August 2007. Retrieved 2007-09-09.
29. "Lavender & Tea Tree Oil Rebuttle(sic)".
30. 'ATTIA refutes gynecomastia link', Article Date: 21 February 2007
31. "Eucalyptus oil".
32. Millet, Y.; Jouglard, J.; Steinmetz, M. D.; Tognetti, P.; Joanny, P.; Arditti, J. (1981). "Toxicity of Some Essential Plant Oils. Clinical and Experimental Study". Clinical Toxicology. 18 (12): 1485–98. doi:10.3109/15563658108990357. PMID 7333081.

External links

• Aromatherapy and Essential Oils – health professional and patient PDQ (Physician Data Query) summaries from the National Cancer Institute.