Despite the long-term and widespread use of aromatherapy, there is little scientific evidence to support its validity in the treatment of disease. We do know from various studies however that olfaction and the sense of smell can have positive effects on mood and the perception of wellness. We are also aware of the beneficial effects of touch and massage on health and must also consider the role of the placebo effect when evaluating the validity of complementary therapies.

    Most research into essential oils has been carried out by the food and drug industries of the United Kingdom and concentrates on the study of ingested oils, a form of aromatherapy rarely used in the US. Limited research on the inhalation of oils has been done in Japan, the US, the UK, and Europe and very little research has been done to verify the mechanism or the benefits of topically applied essential oils. For more information about how essential oils affect the physiology of the body and studies supporting the use of aromatherapy in pain see the following pages.