Aromatherapy is the treatment or prevention of disease by use of essential oils. 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. The other is the direct pharmacological effects of the essential oils<1>. While precise knowledge of the synergy
between the body and aromatic oils is often claimed by aromatherapists,
the efficacy of
aromatherapy remains to be proven. However, some
preliminary clinical studies show positive effects. <2> <3>
In the English-speaking world, practitioners tend to emphasize the
use of oils in massage. Aromatherapy tends to be regarded as a
complementary modality at best and a pseudoscientific fraud at worst.<4>
On the continent, especially in France,
where it originated, aromatherapy is incorporated into mainstream
medicine. There, the use of the
antiseptic, antiviral, antifungal, and
antibacterial properties of oils in the control of infections is
emphasized over the more "touchy feely" approaches familiar to English
speakers. In France some essential oils are regulated as prescription drugs, and thus administered by a physician.
French doctors use a technique called the aromatogram to guide their
decision on which essential oil to use. First the doctor cultures a
sample of infected tissue or secretion from the patient. Next the
growing culture is divided among petri dishes supplied with agar.
Each petri dish is inoculated with a different essential oil to
determine which have the most activity against the target strain of
microorganism. The antiseptic activity manifests as a pattern of
inhibited growth.<5><6>
In many countries essential oils are included in the national pharmacopoeia, but up to the present moment aromatherapy as science has never been recognized as a valid branch of medicine in the United States, Russia, Germany, or Japan.
Essential oils, phytoncides and other natural VOCs work in different ways. At the scent level they activate the limbic system and emotional centers of the brain.
When applied to the skin (commonly in form of "massage oils" i.e. 1-10%
solutions of EO in carrier oil) they activate thermal receptors, and
kill microbes and fungi. Internal application of essential oil
preparations (mainly in pharmacological drugs; generally not
recommended for home use apart from dilution - 1-5% in fats or mineral
oils, or hydrosoles) may stimulate the immune system.