Two 10-minute aromatherapy sessions, using bergamot essential oil, significantly reduced anxiety and enhanced autonomic nervous activity among elementary school teachers, according to recent research.

The study, “Aromatherapy Benefits Autonomic Nervous System Regulations for Elementary School Faculty in Taiwan,” involved 54 elementary school teachers from three schools. Exclusion criteria were possible asthma, hypertension or heart disease.

The Beck Anxiety Inventory was used before the intervention to determine the anxiety level of each teacher, from light to mild to moderate. Each subject received two 10-minute sessions of aromatherapy, which occurred once a week for two weeks, on the same day and at the same time and place each week.

The study employed 100-percent pure bergamot essential oil, which was diluted to 2 percent. An Ultrasonic Ionizer Aromatherapy Diffuser was used for the aroma evaporation. Researchers report choosing bergamot essential oil because previous studies showed it’s effectiveness in reducing anxiety and pain. In addition, bergamot essential oil is relatively inexpensive, widely available and well-tolerated.

Subjects were instructed to avoid cigarettes, alcohol and coffee for six hours before the aromatherapy session. Physiological measures were recorded on the second week of the two-week aromatherapy intervention.

The teachers were asked to rest for five to 10 minutes before the pre-aromatherapy physiological recordings were taken. These recordings included average blood pressure and heart-rate variability parameters over the course of seven minutes, as shown on an ANSWatch monitor.

During the second 10-minute aromatherapy session, these same physiological measures were recorded for seven minutes. After this second aromatherapy session concluded, another seven-minute recording of blood pressure and heart-rate variability was conducted.

Results of the research showed blood pressure, both systolic and diastolic, was reduced immediately following the 10-minute aromatherapy session. Subjects also experienced a decrease in heart rate and an increase in high-frequency power and heart-rate variability, which both correspond with parasympathetic activity—the opposite of anxious sympathetic activity.

Those teachers with moderate and high scores on the Beck Anxiety Inventory showed the most significant improvements with the use of aromatherapy, whereas the teachers with light anxiety were not as fully affected by the sessions.

“In this study, physiological signals were measured after the second once-weekly aromatherapy treatment,” state the study’s authors. “This experiment focused on the short-term relaxing effect instead of tracking the long-term effect of aromatherapy.

“Data showed that aromatherapy would be effective in promoting parasympathetic activity, reducing blood pressure and heart rate,” they continued. “Aromatherapy seems to drive autonomic nervous activity toward a more balanced state.”

Authors: Kang-Ming Chang and Chuh-Wei Shen.

Sources: Department of Photonics and Communication Engineering, Asia University, Taichung, Taiwan; Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan; and Ming-Chien Elementary School of Nantou County, Ming-Chien Township, Taiwan. Originally published in Evidence-Based Complementary and Alternative Medicine (2011).