The research, which was conducted at Ohio State University, put two of the most popular aromatherapy oils to the test. Lavender and lemon essential oils were tested on their measurable healing properties and the findings of the study were published in the International Society of Psychoneuroendocrinology’s journal, Psychoneuroendocrinology.

Janice Kiecolt-Glaser, psychiatry and psychology professor at Ohio State University and co-author of this research, said of the study, “We all know that the placebo effect can have a very strong impact on a person's health but beyond that, we wanted to see if these aromatic essential oils actually improved human health in some measurable way,”

After conducting a series of experiments on the oils, the Ohio-based research team could find no measurable benefits. In fact, in a few cases, distilled water had more of an effect than lavender oil.

In order to test the oils, researchers stuck balls of cotton wool infused with the essential oils and distilled water under the noses of 56 healthy volunteers. Every volunteer was tested prior to the study to ensure that they had a regular sense of smell; they were then made to undergo a series of tests over three sessions.

In order to see whether the scents could help the volunteers to manage pain response, they stuck the subject's feet into icy cold water. To test whether the scents could improve healing, the researchers performed a test where some tape is applied and removed repeatedly to the same spot of skin. In order to test the impact of the oils on mood, the volunteers were asked to complete nine standard psychological tests. Finally, to test the impact of the smells on the volunteers’ stress levels, they underwent regular blood, blood pressure and heart tests.

The tests indicated that neither the lemon nor the lavender essential oil managed to show any positive measurable effect on the immune system. While the lavender oil also failed to show a change in the body's ability to deal with pain or stress, the lemon oil did show a substantial mood enhancement.

William Malarkey, a professor of internal medicine and co-author of this study, concluded, “We failed to find any quantitative indication that these oils provide any physiological effect for people in general.” Still, despite the findings, the professor said that he wouldn’t write off using essential oils and aromatherapy completely. He said, “This is probably the most comprehensive study ever done in this area, but the human body is infinitely complex. If an individual patient uses these oils and feels better, there's no way we can prove it doesn't improve that person's health.”

Source:

Associated Free Press

New York Times