What Do You Really Want To Know About Aromatherapy?


Tom Hildebrandt










Outline: click on an entry to go to that section

Aromatherapy: Purpose
Essential oils.
Table of Components of Essential Oils:
Aromatherapy: How does it work?
Essential oil's mind/body Effect.
Olfactory system.
Aromatherapy: Effectiveness.
Effective claims-commercial.
Effective claims-esthetic.
Effective claims-clinical.
Aromatherapy: Evidence.
Research.
Aromatherapy-myth or actuality?
Intro.
Smell and aromatherapy.
Perfume, Food and Drug
Make up of essential oils.
Essential oils-practical use
Lavender.
Peppermint oil.
Relaxing effect of many essential oils.
Conclusion on essential oils.
Dangers of aromatherapy
Contact Dermatitis reports.
Problems with research
Conclusion
References



Aromatherapy: Purpose

Definition. Aromatherapy is the use of essential oils to help the mind, body, and soul. It has physiological, emotional, spiritual, and psychological properties

(http://www.dawn21.com/MessageMag/Aromatherapy.html). Today, it is a science that includes three fields: esthetic, commercial, and clinical (http://www.dawn21.com/MessageMag/Aromatherapy.html). Some categorize it as a holistic or alternative science. This is an ongoing debate, and the answer depends on who you are asking. Aromatherapy finds its origin in ancient Iraq; some evidence has been found of its use in Iraq some sixty-thousand years ago (http://www.sentex.net/~aquarius/mags/harts/iss95/aroma.html). In the East, herbal medicine is their tradition. In the year 2000 B.C.E., The Yellow Emperor's Book of Internal Medicine contained 8,160 different formulae. These formulae were mostly herbal compounds, some of which can be related to present day aromatherapy (htpp://www.sentex.net/aquarius/mags/harts/iss95/aroma.html). At the same time India was almost entirely plant based. Indian scriptures listed the use of aromatherapy for liturgical, therapeutic, and pleasurable purposes. As far back as 3000 B.C.E., the Chinese were using aromas with acupuncture and message (htpp://www.sentex.net/~aquarius/mags/harts/iss95/aroma.html). These plant based ideas are what modern day aromatherapy is based on.

Essential oils.



The science of aromatherapy is based on essential oils. These oils are primarily plant hormones which contain carbon, hydrogen, and oxygen (http://www.dawn21.com/MessageMag/Aromatherapy.html ). In life, these elements are fundamental. Essential oils combine the fundamental elements in many "mono- and sesquiterpenic families of hydrocarbons, alcohols, ketones, acids, phenols, esters, and coumarines" (http://shell.glo.be/~jeanmich/mi_eng14.html). A list of the components of essential oils is as follows:

Table of Components of Essential Oils:

Aliphatic Chains:

These are slightly antiseptic and bactericidial, analgesic, expectorant and stimulating.

Sequiterpenes:

Antiseptic, bactericidal, anti-inflammatory, calming and slight hypotensors, some are analgesic and/or spasmomytic.

Diterpenes:

Expectorant, purgative, some are antifungal, and antiviral, some appear to have balancing effect on hormonal system.

Alcohols:

Anti-infective, strongly bacterial, antiviral and stimulating; they are generally nontoxic in use and do not cause skin irritation.

Phenols:

They are antiseptic and bactericidal. They stimulate the both the nervous system and the immune system, they activate the body's own healing process.

Aldehydes:

Antiviral, anti-inflammatory, calming to the nervous system, hypotensors, vasodillators and antipyretic; their negative properties-when used incorrectly-can cause skin irritation and skin sensitivity.

Ketones:

Cicatrizant, lipolytic, mucolytic, and sedative, some are also analgesic, anticoagulant, or stimulant. Organic Acids and Esters Antifungal. anti-inflammatory, antispasmodic, cicatrizant and both calming and tonic, especially to the nervous system. Like alcohol, they are gentle in action, and being free from toxicity they are "user friendly".

Oxides:

The only known well to aromatherapy is 1,8 cineole, otherwise known as eucolyptol; it may also be regarded as bicyclic ether. Eucalyptol is expectorant and mucolytic.

Lactones:

They occur only in the expressed oils and some absolutes because the molecular weight is too great to allow distillation. Lactones are reputed to be mucolytic, expectorant and temperature-reducing, their negative aspects being skin-sensitizing and phototoxicity.

Coummarines and Forocoummarines:

Coummarines are anticoagulant hypotensors, they are also uplifting yet sedative. Forocoummarines are known mainly for their phototoxicity. Some are anti viral and anti fungal.
The information for this table was taken from htpp://shell.globe/~jeanmich/mi_eng14.html:




Essential oils are found in the spaces between plant cells (http://www.sentex.net/~aquarius/mags/harts/iss95/aroma.html). This only applies to about 20% of all plants. Essential oils are released by the plant to deal with stress. They, also, act as the plants immune system, and they are what the plant uses to heal its body (http://www.sentex.net/~aquarius/mags/harts/iss95/aroma.html). There are many ways to obtain essential oils from plants; for example, steam distillation, cold pressing, chemicals, or fat-absorption

(http://claim.goldrush.com/~jayde/at.html). The most popular one is steam distillation. This process is what the major industries use to manufacture essential oils. It is said the reason for the expense of essential oils is the fact that they are hard to obtain in high quantity

(http://www.halcyon.com/kway/details.htm). For example, it takes 440 pounds of fresh lavender to produce two and a half pounds of lavender essential oil (http://www.halcyon.com/kway/details.htm).




Aromatherapy: How does it work?


Essential oil's mind/body effect.



Essential oils can be delivered to the body in two ways. They enter through the skin, as in massage, or through the nose, as in aromatherapy. The main body system used in aromatherapy is the olfactory system

(http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpapper.html). The olfactory system is how we smell. It is related to the emotional part of our brain

(http://www.holistic.com/essays/aromat01.html). The technical name for this system is the limbic system (http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpaper.html). This effects both the endocrine and hormonal systems through the hypothalamus (http://www.holistic.com/essays/ar0mat01.html). In massage, the oils seep through the skin and into "extra cellular liquids" (htpp://www.holistic.com/essays/aromat01.html). From there they reach the blood or lymph and are carried to the place of need in the body (htpp://www.holistic.com/essays/aromat01.html). Massage is sometimes related to aromatherapy because of its use of essential oils.

There is a "twin pronged" effect described when discussing essential oil (http://www.dawn21.com/MessageMag/Aromatherapy.html). This effect involves the distinction of body and mind. Although aromatherapy is said to have a nondualistic working method, there are two distinct ways that essential oils work. If the origin of the problem is in the psyche, it uses neuroendocrine functions to deliver a response to the body. If the origin of the disease is in the body, it works through physiological functions to deliver a response to the mental or emotional levels of the psyche (http://www.dawn21.com/MessageMag/Aromatherapy.html). The real emphasis in aromatherapy is in the smell, or psyche to body, working method. The other working methods, such as massage, are not considered true aromatherapy, but they are closely related.

Olfactory system.



"Aroma", fundamentally, is associated with smell. Since aromatherapy is a science that uses the sense of smell to create a desired effect, it must use the olfactory system to get a desired response. This system is found in the nose. Within the nose there are "hair-like" branches that come out of sensorial neurons (http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpaper.html). These branches come together to form the olfactory nerve. This nerve sends impulses to the brain which stimulates a reaction that causes the sense of smell. The nerve receives the "smell" in gaseous state through the nose. The "smell" must be both water and lipid soluble. The olfactory nerve is mucous covered (http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpaper.html). This is the reason for water solubility. The hairs on the olfactory nerve have a largely lipid, plasma membrane. For a "smell" to make contact with the hairs it must dissolve through the membrane; thus, it must be lipid soluble (http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpaper.html). The nerve stimulates the brain and a response occurs. Knowing what essential oils stimulate what responses is the art of aromatherapy.


Aromatherapy: Effectiveness.


Effective claims-commercial.



The division of aromatherapy that is commercial has many claims of what this science can do for you. The people who endorse aromatherapy tend to use the word "natural" when referring to the science (http://www.sentex.net/~aquarius/mags/harts/iss95/aroma.html). The basic claims deal with fighting of disease, managing depression and stress, relieving headaches and muscular tension. When dealing with any retailer, you'll find a list of essential oils and their specific healing qualities. There will, also, be a list of devices used to turn the oil into an aroma. Most aromatherapy retailers combine massage with aromatherapy to appeal to a larger audience. This is due to the use of essential oils that can work through aroma or message. When dealing with these retailers, it is important to look for evidence. They always claim that these oils can heal you, but they rarely consider proof of their claims. They hide this lack of proof through mention of the ancient arts or some sort of historical justification. Some retailers will, actually, offer evidence of studies, but the references are often vague. Aromatherapy is a rapidly growing commercial industry. Its applications can be seen in the perfume industry

(http://dspace.dial.pipex.com/town/square/aaj84/index.htm). For example, Estee Lauder's product line, Origins, claims to use aromatherapy (http://dspace.dial.pipex.com/town/square/aaj84/index.htm). The commercial side of aromatherapy is based on money. There are applications of "environmental fragrancing" in everything from the workplace to subliminal fragrancing of printed magazines (htpp://www.dawn21.com/MessageMag/Aromatherapy.html). This is just the commercial side of the industry.


Effective claims-esthetic.

The claims of esthetic aromatherapy are purely pleasurable. The commercial industry has also taken advantage of this side of aromatherapy. Esthetic aromatherapy mainly deals with meditation. It relies on perfumes, ointments, diffusers, and ointments (http://www.dawn21.com/MessageMag/Aromatherapy.html). It intends to make you happy or help you relax in use with meditation (http://www.dawn21.com/MessageMag/Aromatherapy.html). Some oils claim to be aphrodisiacs. This is related to the "happiness" effect of aromatherapy and is put under the category of esthetic aromatherapy (http://www.halcyon.com/kway/details.htm). Both esthetic and commercial aromatherapy refer to the lists of essential oils and their uses for the claims they make.


Effective claims-clinical.

Clinical aromatherapy claims preventative and curative properties of essential oils. It, unlike commercial and esthetic aromatherapy, is a science. It is the only one that uses fact through studies to back its claims. It is, just now, becoming an practice like herbal medicine (http://www.dawn21.com/MessageMag/Aromatherapy.html). It uses aromatherapy and massage to treat disease and psychological problems. There is interest in aromatherapy by psychologists which may be a reason for its increased study in the last decade. All the information about aromatherapy is coming out of this field(htpp://www.dawn21.com/MessageMag/Aromatherapy.html). Its claims are limited but there is evidence of the scent of lemon making people more alert and more productive in the workplace (http://dspace.dial.pipex.com/town/square/aaj84/index.htm). When considering aromatherapy, it may be helpful to look into a clinical aromatherapist's research.

List of essential oils and their uses. The uses of essential oils sum up the claims of the entire science of aromatherapy. Here are just a few of them in the following table:

Essential oils and their uses:

Sweet basil:

Invigorates body and spirit: helps refresh the mind allowing concentration, especially when tired. It has a sweet liquorice-like fragrance. Warning do not use when pregnant

Bergamot:

Relaxes and refreshes and is good for confidence building. Uplifts the spirit and emotions with delicious fresh and invigorating citrus fragrance. Useful for caring for oily and blemished skin. Lovely citrus aroma. Warning Do not apply to the skin before going out into the sun - It can increase the susceptibility of the skin to severe burning.

Cedarwood Virginia:

Soothes and harmonizes. Recognized as a therapeutic oil from ancient times. An astringent oil useful for protection and caring for oily and blemished skin, and as an inhalant relieves mucoussy coughs and colds. Helps combat cellulite, use in wardrobe to repel moths. It makes a pleasant warm and woody room fragrance, the Tibetans use it as temple incense. Warning Use Cedarwood during pregnancy only in moderation

Eucalyptus:

Powerful antiseptic, widely used in baths and massage during cold season. Blend oil in chest rubs and use in a vaporizer to keep air germ free in sick room

Frankincense:

Also known as "Olibanum". Soothes, warms and aids meditation. It has been used for centuries, and burnt on alters and in temples. "Creates a 'spiritual' atmosphere". Comforting oil, by slowing down breathing and controlling tension it helps to focus the mind. Excellent for toning and caring for mature/aging skin. (claimed to have rejuvenating qualities[the Egyptians used it to rejuvenation face-masks]).

Geranium:

A balancing oil for the mind and body. A fresh, floral and sweet smelling oil it relaxes, restores and maintains stability of the emotions. An astringent oil excellent for all skin types. Used in skin care products for both its fragrance and cleansing properties. Useful insect repellent. For massage where there is cellulite and treating eczema and psoriasis.

Jasmine Absolute:

Emotionally warming. Relaxes, soothes, uplifts and helps self confidence. Good for stress and general anxiety. Perfect skincare oil, excellent for hot, dry skin. Sensual properties and reputedly an Aphrodisiac!. Only needs to be used in small quantities. Exquisite perfume. A vast quantity of blossoms, which must be gathered at night when their scent is at their highest, are required to produce only a few drops of oil, so it is a very expensive oil,

Juniper:

Tones and stimulates. an antiseptic and astringent oil for bath and massage where there is cellulite. Restores psychic purity. Fresh woody aroma. Has a cleansing effect on the body, used in many masculine perfumes, after shaves and colognes, and has a calming effect on the emotions. Reputed to strengthen the immune system. {And don't forget the Gin} Warning Juniper should not be used when pregnant.
The information for this table was taken directly from a company trying to sell "aromatherapy". The liberties of punctuation and grammar were taken by the company involved. The information from this table can be found at http://www.demon.co.uk/murderon/fragrant/aroma2.html





This list of essential oils shows roots in clinical, esthetic, and commercial aromatherapy. Upon examination of the properties of these oils, you will find that they talk of meditation, perfume and colognes, and antifungal and antibacterial qualities. These are examples of the three branches of aromatherapy. Pay attention to the wording. It is slanted to make the products seem effective; also, note the historical reference for justification. This table shows what you will find if you look for the effects of aroma.

Aromatherapy: Evidence.


Research.

Much of the research is still in process. There are several institutes that are currently investigating the properties of essential oils. The two that I found are Monell Chemical Senses Center, in Philadelphia, and Sloan Kettering Memorial Cancer Center, in New York (http://dspace.dial.pipex.com/town/square/aaj84/index.htm). Of interest to psychologists, The Sloan Kettering Memorial Cancer Center conducted a study that proved that the smell of vanilla helped patients cope with stress (http://dspace.dial.pipex.com/town/square/aaj84/index.htm). There is also a study by of a group of scientists, headed by Dr. Walter J. Freeman, P.I., that is investigating the effects of neuroactive chemicals on the brain (http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpaper.html). Included in this study is the investigation of patterns of activity in the olfactory bulb as it relates to ongoing motivated behavior (http://www.leesummit.k12.mo.us/projects/aromatherapy/researchpaper.html). Many of the antiseptic and antibacterial properties of essential oils were studied by Chamberland in 1887 and Dr. Jean Valnet in 1963 (http://shell.glo.be/~jeanmich/mi_eng15.html). There, of course, were many more researchers of these oils, but there isn't much mention of them on the Internet. They are probably the originators of the claims behind aromatherapy. As far as the claims of the retailers, they claim that experience in the field leads to proof. Among the many words that are used over and over again to describe the effects of aromatherapy are relaxing, uplifting, emotionally stimulating, soothes and warms, cleanses, and sensual. These words are used without justification, but they are affective in making aromatherapy sound appealing. Along with these descriptions are many physiological claims. These include curing headaches and forms of chronic pain as well as many claims of killing bacteria and repelling insects. The truth of these claims is not within the words of retailers but in the research of scientists.

Aromatherapy-myth or actuality?


Intro.

The practice of aromatherapy is spreading like wildfire. In a time of advertising and fast money, is aromatherapy another quick money scheme that doesn't work or is it an affective form of therapy that has scientific evidence to back its claims? With the increase use of alternative medicine in western culture, the popularity of aromatherapy has grown. This alternative therapy is based on the use of essential oils for therapeutic reasons. There are many allegations that individual companies claim to be true, but there base for these claims are not strong. Most involve personal testimonies, and very few use actual scientific research. In fact, most of the studies that involve aromatherapy are done on the essential oils that aromatherapy uses. The research doesn't have the aim to prove or disprove aromatherapy, only study the properties of essential oils. This is important, considering the fact that essential oils are used in the cosmetic and message industry. Despite the cosmetic or massage based slant in the research discussing aromatherapy, there is hope in the search for the truth behind this popular alternative medicine. Most of this research is recent and there are currently studies that have an aromatherapeutic slant. However, these studies are not always ready to be published, and it is not possible to claim these studies as proof of the effectiveness of aromatherapy yet. For this reason, a search of the existing research was done and the findings are reported below. Due to the obscurity of some of the journals, mention of cited studies is given to help establish a firmer understanding of the research that has been done.


Smell and aromatherapy.

Before a look into actual aromatherapy is done, the "how" part of aromatherapy must be discussed. The mechanics of smell are a well researched and a non controversial topic. The mechanics of aromatherapy are based on these same mechanics. Within the study of mechanics of smell, there is research that pertains to aromatherapy. The book, Odor Sensation and Memory, cites studies done by Rovesti and Colombo (1973) that suggest some essential oils are sedatives and others have stimulant properties (Engen, Trygg 54-56). These properties can be used to "manipulate interpersonal relations and cure psychiatric problems" (Engen, Trygg 54-56). There are several other studies that back claims similar to this one, but the actual studies are published in obscure journals. These studies are some of the few that suggest research into the behavior changes through aroma of essential oils. They show evidence of the aroma affecting the brain in the case of essential oils. These studies, obscure as well, will only be mentioned and not used as evidence (Engen, Trygg p.54-55). The effect of aroma on the brain and use for therapeutic purposes is something that has renewed interest. Health has named a number of ongoing, unpublished, or inaccessible research that is related to this topic (Freifield, K p. 59-63, 84-85). To avoid bias, these studies are not mentioned, but, if interested, it may be helpful to look at the cited articles in this text for further reference. All in all, the mechanics of aromatherapy haven't been effectively studied, but its basis is sound and research linking the mechanics to the "aroma" of aromatherapy is becoming more common and available.


Perfume, Food and Drug


Research of plants-analysis.

There is no significant research dealing with the aromatherapy side of plant research. The research that exists is mostly on essential oils. These oils are studied in the form of there components. Of course, there happen to be hundreds of components involved in essential oils. The studies that involve essential oils as themselves are dealing with specific properties. These studies do not necessarily back up the same claims when these oils are used in aromatherapy, but they do offer suggestions on the properties of the oils. These studies are examples of the kinds of studies that may be manipulated into proof of aromatherapy. When considering these studies, remember they were done by either the FDA or the perfume industry. Because of this, they do not intend to prove or disprove aromatherapy.

Antibacterial qualities.

The evidence of the antibacterial qualities of essential oils are cited references of published material in obscure journals. The 1949-50 Report on Essential Oils, Aromatic Chemicals and Related Materials cites a study by Schroeder and Messing (1949) that shows the antibacterial qualities of cinnamon, pine, and Australian tea oil (Schimmel & Co. Inc. p.55-56). There are similar studies of the antiseptic effects involving lemongrass oil by Bose, Bhima, and Subrahamyan (1949) and the effectiveness of sage oil on oral bacteria by Brieskorn (1950) is also mentioned. It is accepted that there are antibacterial qualities to essential oils. My search revealed that the material found is mentioned in other studies as well as these and appears to be accepted by most researchers. It is safe to say that essential oils have antibacterial properties, but this does not justify the claims of aromatherapy retailers.



Make up of essential oils.


The make up of essential oils is not a mystery. There are countless studies that show the make up of these oils. Table 1 shows some of the make up of a few oils backed by research. Table one, however, suggests a chemical slant to aromatherapy. The chemical side of this research is very broad. Studies on these chemicals are numerous, but none of them give proof to aromatherapy.


Table 1: Essential Oils and Their Constituents

Sweet Basil: contains 80-85% methyl chavicol & small amounts of cineol, linalool and d-a-pinene (Schimmel report p.4)
Bergamot contains 54.2% oxygenated constitutes and bisabolene, B-caraophyllene, and a bicyclic sesquiterpene named bergamotene (Schimmel report p.4-5)
Cedarwood Virginia 15 constitutes: some are Myrcene, terpinolene, tar, acyclic ketone, sesquiterpene, caryophyllene, and fin hydrocarbon (Schimmel report p.6-7)
Eucalyptus contains citronellol, aledehyde, terpenic oil, citronella, and cineol (Schimmel report p. 9-10)
Frankincense no reference found
Geranium contains citronellol, ketones, and esters (Guenther, v. iv p.698)
Jasmine Absolute contains ester, benzyl benzoate, indole, and methyl anthranilate (Guenther, v. v p.328)
Juniper no reference found



This table does not represent the complete make up of the individual essential oils. However, the information can lead to another angle of research that may support the claims of aromatherapy. The individual components of the oils have properties themselves. These properties may be sources for claims of aromatherapy. Research on this topic may give further insight into the claims of aromatherapy. But because of it's indirect affect on the claims of aromatherapy, a thorough examination of the research was not included.


Essential oils-practical use


Lavender.

The most researched and used essential oil is lavender. It has many applications, and many studies that back up its properties. For example, the National Cancer Institute shows the effects of lavender on cancer. These studies were not officially cited in the Journal of the National Cancer Institute article in which they were mentioned. To look further into the truth of this claim consider the University of Wisconsin, Madison, study on the effects of lavender and rats. According to Journal of the National Cancer Institute, the research shows that lavender prevented tumors from developing and caused "complete transgression of advanced mammary tumors" in rats(Ziegler, J. p. 1102). It is known that Lavender contains perilly alcohol which is used in treatment of cancer, but this alcohol alone has side effects (Ziegler, J. p. 1102). It is the purpose of the studies mention to develop a lavender treatment that has no side effects (Ziegler, J. p. 1102).

The anti-carcinogen effects of lavender are not its only use. Dunn, Sleep and Collett (1995) show that lavender is affective for patients in intensive care units. This study included 122 patient that were randomly assigned either massage, a period of rest, or aromatherapy with lavender. There was an assessment of the physiological stress indicators before and after the each treatment during the five day period. Along with this, anxiety and the ability to cope with intensive care experience were tested. This information was assessed and reviewed to eliminate bias. The results show that aromatherapy with lavender oil did not show significant differences in the physiological stress indicators or the behavior of the patients ability to cope. Upon further examination of the data, it was determined that the patients receiving the treatment with aromatherapy showed a decrease in their anxiety levels and overall mood. This study suggests that aromatherapy could effectively be used to lower anxiety levels in intensive care situation-however, more research should be done in this area before actions are taken.

Lavender as an essential oil is suggested as effective in relieving perineal discomfort following childbirth. In a blind randomized clinical trial, Dale and Cornwell (1994) show that six drops of lavender added to bath following childbirth can reduce perineal discomfort earlier. There were two substances used. One was lavender, the other was a synthetic lavender oil. The study was done over the ten days following childbirth and included 635 women. The study showed that between the third and fifth days, when discomfort is normally high, there was a lower discomfort score given by the women. The results were recorded by a questionnaire given to the women following each bath. There were no side-effects recorded and no conclusive proof found. However, there is evidence that suggests that the lavender oil could reduce the discomfort earlier, but not the overall discomfort.

There are many concerns among aromatherapists about the oils being natural. Buckle (1993) showed that the effectiveness of a synthetic lavender oil was almost twice as effective as the natural lavender oil. In this double-blinded trial, the two lavenders were applied to post-cardiotomy patients. The behavioral and emotional stress levels of 28 patients were analyzed both before and after treatment. The results showed that the synthetic hybrid was more effective. Another interesting outcome of this study is the disapproval of the belief that essential oils are only effective due to massage or placebo. This study supports essential oils, but does nothing for the "aroma" in aromatherapy. This, again, is the side of aromatherapy that is not researched.


Peppermint oil.



There are studies on peppermint oil that show that this essential oil has a relaxation quality. Dew, Evens, and Rhodes (1984) showed that peppermint oil was affective in the treatment of irritable bowel syndrome. This double blind crossover study included 29 patients from seven different hospitals. Each patient was given a placebo or peppermint oil capsule. The patients filled out a questionnaire daily. The abdominal symptoms were graded; stool frequency recorded; and, the side-effects noted. The patients that took the peppermint oil capsule recorded less abdominal symptoms. This study shows that peppermint oil is a relaxant for smooth muscle. The study also suggests the use of peppermint oil for irritable bowel syndrome. Sparks, O'Sullivan, Herrington, and Morcos (1995) studied the relaxation effects of peppermint oil as well. There study involved the relief of spasm during barium enema. Two groups of a total of 141 patients were involved. The first group did not receive the peppermint oil during treatment while the second did. The peppermint oil reduced the incidence of colonic spasm during the treatment. The films of the treatment were reviewed by radiologists to determine the results. The radiologists were also graded on their evaluation to eliminate bias and human error. A bonus to this study was the lack of side effects of the peppermint oil. Again, these studies do not support aromatherapy, but they may serve as a base for claims of essential oils. In this case, the studies would tend to support the relaxation qualities of peppermint oil when they haven't been tested in the form of behavior or emotion. However, the studies do prove that peppermint oil has a relaxing effect.



Relaxing effect of many essential oils.



Reiter and Brandt (1985) showed the relaxation effects of 22 essential oils in their study involving 11 different plant families. They used a guinea pig to examine the relaxation effects on the tracheal and ileal smooth muscles. Their study showed the all of the oils had relaxant effects on the tracheal muscle. Only 16 of the oils had relaxant effects on the phasic contractions of the ileal myenteric plexus-longitudinal muscle. Two of the oils increased the phasic contractions and four of the oils increased the resting force. Most of the oils had a more potent effect on the ileal than the tracheal, but four had an increased affect on the tracheal. This data suggests that there are many essential oils with relaxant qualities.


Conclusion on essential oils.



Currently there is not enough research on essential oils in relationship to aromatherapeutic claims. There is a plethora of research on essential oils and there individual properties and components, but there is a lack of research that relates the oils to effective claims dealing with aromatherapy. It is apparent that aromatherapists must base some of its claims on the research of essential oils. Aromatherapy advertisements, however, take the liberty of relating oil qualities to aromatherapy's practice without sufficient data. There are some studies that relate the two, but must are not published or published in obscure journals. The following table lists the support found on a few selected essential oils.


Table 2: Essential Oils and Their Claim Support

Sweet Basil:

relaxant effects [Rieter and Brandt (1985)] not emotional

Bergamont:

no research found

Cedarwood Virginia:

no research found

Eucalyptus:

no research found

Frankincense:

no research found

Geranium:

no research found

Jasmine Absolute:

no research found

Juniper:

no research found






Dangers of aromatherapy


Contact Dermatitis reports.



There are several reports and studies done that prove that essential oils are not totally safe. Selvaag, Erikson, and Thune (1994) reported that tea tree oil has the possibility of contact allergy. This study also showed that tea tree oil can relieve acne with less side-effects than regular treatment. The results said that eucalyptol was the allergen that caused the specific case study to have an allergic reaction. Bossuyt and Dooms-Goossens (1994) reported a similar case study that revealed that camomile is also an allergen. Audicana and Bernaola (1994) showed that lemon oil and orange oil can be allergens. They did a patch study that observed positive reactions from lemon, lemongrass, neroli, and geraniol oils. Selvaag, Holm, Thune (1995) studied the reactions to 20 essential oils. This study was brought on by a case of dermatitis by an aromatherapist. Use with essential oils brought on an allergic reaction. The results of the patch test are shown below. The method used to determine the level of reaction was a positive, negative rating. The positive showed the level of the reaction and the positive reaction to it. The negative showed a null affect of testing. Note the fact that most essential oils have an allergenic quality.

Table 3: Essential Oils and Their Patch Test Results 5% Pet.

ylang-ylang:

positive positive

myrrh:

positive positive

frankinscense:

positive positive

chamomile:

positive positive

cypress:

positive positive

rosewood:

positive positive

geranium:

positive positive

vetiver:

positive positive

basil:

positive positive

lavender:

positive positive

majoram:

positive positive

peppermint:

positive

sage:

positive positive

eucalyptus:

positive positive

tea-tree:

positive positive

bergamot:

negative

lemon:

positive positive

orange:

positive positive

sandalwood:

negative

benzoin:

positive positive


Conclusion. It is proven that essential oils can be dangerous. They are proven to have allergic side effects. This should be considered in the use of aromatherapy. It is important to be cautious when using essential oils in message. This is the main cause of allergic reaction. There are often precautions given by the commercial industry about concentrations of essential oils. These precautions should be followed because there is definite proof of side-effects of aromatherapy. Of course, there is less research done on the side-effects due to aroma and not direct contact, but caution is suggested.


Problems with research


Problems. There are many problems with the research on aromatherapy. The biggest one is that it does not exist. There is a definite lack in the "aroma" side of aromatherapy. Most of the research is spread out and deals with essential oils and direct application. Although aromatherapy and massage are being used together, there is no significant evidence that aromatherapy works by itself. The studies that are accessible are small, individual experiments that are scattered among the list of hundreds of essential oils. Another problem lies in the fact that most research is not intended to justify aromatherapy. It is based on essential oils. Until recently, the studies done on these oils were by the perfume industry and backed by the FDA for safety. The final, and most frustrating, problem is the fact that many studies are ongoing or not ready for publication yet. In the next few years, an abundance of information will become available concerning the practice of aromatherapy. The interest in alternative medicine has freed up more money for research in this area, and will slant the research towards the "aroma" side of the therapy.


Conclusion


Conclusion. With the given information, it would be impossible to say that most of the claims of aromatherapy are justified. There were not enough studies available to significantly back the claims of aromatherapy. That, however, does not mean that there is no evidence. Many interesting studies are ongoing in this field, but are unpublished This limits the search for evidence. Remember that advertisers tend to exaggerate their claims and use personal testimonies to back them. The studies found do not back up the claims of these testimonies, but some do provide a base to their claims. It is safe to say that aromatherapy is not totally unjustified, but only time will provide significant scientific evidence of these claims such as headache relief, cure for insomnia, chronic pain relief, aphrodisiac, and insect repellent.


References


Audicana, M., Bernaola, G. (1994).

Occupational Contact Dermatitis From Citrus Fruits: Lemon Essential Oils. Contact Dermatitis, 31(3): 183-5.

Bossuyt, L., Dooms-Goossens, A. (1994).

Contact Sensitivity to Nettles and Camomile in 'alternative' remedies. Contact Dermatitis, 31(2): 131-2.

Buckle, J. (1993).

Aromatherapy. Nursing Times, 86(20): 32-5.

Dale, A., Cornwell, S., (1994).

The Role of Lavender in Relieving Perineal Discomfort Following Childbirth: A Blind Randomized Clinical Trial. Journal of Advanced Nursing, 19(1): 89-96.

Dew, MJ., Evans, BK., Rhodes, J. (1984).

Peppermint Oil for the Irritable Bowel Syndrome: A Multicentre Trial. British Journal of Clinical Practice, 38(11-12): 394, 398.

Dunn, C., Sleep, J., Collett, D. (1995).

Sensing an Improvement: An Experimental Study to Evaluate the Use of Aromatherapy, Massage and Periods of Rest in an Intensive Care Unit. Journal of Advanced Nursing, 21(1): 34-40.

Engen, Trygg., (1991).

Odor Sensation and Memory. Praeger Publishers, New York: 54-56.
1. Rovesti, P., Colombo, E. (1973). Aromatherapy and Aerosols. Soap Perfumery and Cosmetics, 47: 475-477.
2. Van Toller, S., (1988). Emotion and the Brain. In Van Toller & G. H. Dodd (Eds.), Perfumery. The Psychology and Biology of Fragrance (pp. 121-146). London/New York: Chapman and Hall

Friefeld, K., (1989).

Led by the Nose. Health, November 1989: 59-63, 84-85.

Guenther, E., (1952).

The Essential Oils. D. Van Nostrand Co., Inc. New York, IV: 698, V: 328.

Hardy, M., Kirk-Smith, MD., Stretch, DD., (1995).

Replacement of Drug Treatment for Insomnia by Ambient Odour. Lancet, 346: 701.

Reiter, M., Brandt, W., (1985).

Relaxant Effects on Tracheal and Ileal Smooth Muscles of the Guinea Pig. Arzneimittel-Forschung, 35(1A): 408-414.

Schimmel & Co., Inc. (1952).

The 1949-50 Report on Aromatic Chemicals and Related Materials. Schimmel & Co., Inc., New York. pp. 4-7, 9-10.

Selvaag, E., Eriksen, B., Thune, P., (1994).

Contact Allergy Due to Tea Tree Oil and Cross-sensitization to colophony. Contact Dermatitis. 31(2): 131-2.

Selvaag, E., Holm, JO., Thune, P., (1995).

Allergic Contact Dermatitis in an Aromatherapist With Multiple Sensitizations to Essential Oils. Contact Dermatitis. 33(5): 354-5.

Sparks, MJ., O'Sullivan, P., Herrington, AA., Morcos, SK. (1995).

Does Peppermint Oil Relieve Spasm During Barium Enema?. British Journal of Radiology, 68(812): 841-3.

Ziegler, J. (1996).

Raloxifene, Retinoids, and Lavender: "Me too" tamoxifen Alternatives Under Study. Journal of the National Cancer Institute, 88(16): 1100-1102.


By: Tom Hildebrandt

 

 

 

Psychology Department

The Health Psychology Home Page is produced and

maintained by David Schlundt, PhD.
 
 


 

 
List of Resources
  Return to the Health Psychology Home Page
  Send E-mail comments or questions to Dr. Schlundt

 


Search

Search: Vanderbilt University
the Internet

  Help  Advanced

Tip: You can refine your last query by searching only the results by clicking on the tab above the search box


 

Vanderbilt Homepage | Introduction to Vanderbilt | Admissions | Colleges & Schools | Research Centers | News & Media Information | People at Vanderbilt | Libraries | Administrative Departments | Medical