Schneider, R. (2020) Essential oil inhaler (AromaStick®) improves heat tolerance in the Hot Immersion Test (HIT). Results from two randomized, controlled experiments.Journal of Thermal Biology,87. doi.org/10.1016/j.jtherbio.2019.102478
Background: A recent review article on an aromatherapeutic inhaler demonstrated clinical effects on a number of bodily systems, like the cardiovascular system, the respiratory system, the nervous system and the endocrine system.
Objective: This paper extends these findings and investigates whether specially designed essential oils inhalers are capable to counter experimentally induced stressful heat sensations.
Method: Two prospective, randomized, controlled experiments using the Hot Immersion Test Paradigm (HIT) were conducted to investigate whether deep odor inhalations increase heat tolerance.
Results: In both experiments, the inhaler strongly prolonged pain tolerance and increased blood oxygenation (1 < d < 1.3). In the second experiment, the inhaler also increased heart rate variability (d = 1.3) as a mechanism to cope with heat stress.
Conclusion: The ability to resist a stressful thermal stimulus can be exogenously improved by short and deep inhalations of essential scents directly delivered to the olfactory system.