Psychological Stress
Conditions
Keywords
Stress, Aromatherapy, Essential Oils, Autonomic Nervous System, Stress Reactivity, acute stress, anxiety
Brief summary
This randomized, double-blind, placebo-controlled study evaluates the acute physiological and subjective responses to essential oil inhalation in healthy adults. Participants are assigned to inhale either an essential oil or a placebo via an aroma stick during standardized laboratory procedures designed to induce temporary psychosocial stress (Trier Social Stress Test - Group version) and during a guided relaxation session. Physiological responses, including heart rate, heart rate variability, and electrodermal activity, are measured using a wearable sensor. Subjective stress and affect are assessed using validated questionnaires and visual analog scales. The purpose of this study is to characterize short-term autonomic and self-reported responses associated with essential oil inhalation under controlled experimental conditions. This study is exploratory and is not intended to diagnose, treat, or prevent any medical condition.
Detailed description
Essential oils and essential oil blends are widely used in non-clinical settings; however, objective data describing short-term physiological and subjective responses to inhalation under controlled experimental conditions remain limited. This study is designed to evaluate acute autonomic and self-reported responses to essential oil inhalation during standardized laboratory procedures involving psychosocial stress and guided relaxation. This is a randomized, double-blind, placebo-controlled, parallel-group study conducted in healthy adults aged 18-45 years. Participants are assigned to inhale either an essential oil (or essential oil blend) or a placebo comparator administered via an identical aroma stick. Inhalation occurs at standardized time points during two study visits. During Study Visit 1, participants undergo the Trier Social Stress Test - Group version (TSST-G), a validated laboratory paradigm designed to induce temporary psychosocial stress through public speaking and mental arithmetic tasks performed under observation. Inhalation occurs during baseline, preparation, stress, and recovery phases. During Study Visit 2, participants undergo a structured guided meditation session under controlled environmental conditions, with inhalation occurring at standardized intervals. Physiological measures are collected continuously using a wrist-worn wearable device capable of measuring heart rate, heart rate variability (HRV), and electrodermal activity (EDA). Subjective responses are assessed using validated instruments including visual analog scales for stress and calm, PROMIS Anxiety, GAD-7, and PANAS. The primary outcome is change in stress response as measured by area under the curve (AUC) for visual analog scale stress scores across the stress and recovery period. The study employs an adaptive design with an initial planned enrollment of 100 participants (50 per arm) and a prespecified interim analysis for potential expansion to a maximum of 200 participants. Statistical analyses include comparison of stress and physiological responses between groups using baseline-adjusted models. This study is exploratory in nature and is intended to characterize acute responses associated with essential oil inhalation under controlled conditions. It is not designed to diagnose, treat, mitigate, or prevent any disease or medical condition.
Interventions
OTHEREssential Oil Inhalation
Participants inhale an essential oil or essential oil blend administered via an individual aroma stick. At prespecified time points during baseline, stress induction (Trier Social Stress Test - Group version), and recovery or guided meditation procedures, participants are instructed to take five normal breaths from the aroma stick. The intervention is delivered in a randomized, double-blind manner and is standardized across participants within each study phase.
OTHERPlacebo Aroma Stick
Participants inhale a placebo comparator administered via an aroma stick identical in appearance and delivery method to the experimental intervention but without active essential oil components. The inhalation schedule and procedures are identical to those used in the experimental arm to maintain blinding.
Sponsors
dōTERRA International
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
DOUBLE (Subject, Investigator)
Intervention model description
Participants are randomized in a 1:1 ratio to one of two parallel groups: essential oil inhalation or placebo inhalation. Randomization is maintained across two study visits. Participants remain in their assigned group for the duration of the study. An initial cohort of 100 participants (50 per arm) will be enrolled, with a prespecified interim analysis to determine whether enrollment will expand to a maximum of 200 participants.
Eligibility
Sex/Gender
ALL
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
Age 18-45 years, inclusive Able to read, write, and understand English Willing and able to provide informed consent Willing to attend two in-person study visits Generally healthy, as determined by medical history and screening review
Exclusion criteria
Known asthma, chronic obstructive pulmonary disease (COPD), significant lung disease, heart disease, or other medical condition that may compromise safety or data integrity Pregnancy or pregnancy within the past 90 days Known allergy or sensitivity to essential oils or study placebo materials Current smoking, vaping, chewing tobacco, or use of recreational drugs Regular use of essential oils applicable to the study phase (\>3 times per week for ≥2 weeks within the past month) without a minimum 1-month washout Unwillingness to abstain from alcohol for at least 72 hours prior to each study visit Failure to meet inclusion criteria
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Visual Analog Scale (VAS) Stress Area Under the Curve (AUC) | Baseline through 30 minutes post-stressor recovery (Study Visit 1) | Area under the curve (AUC) for self-reported stress measured using a Visual Analog Scale (VAS) across baseline, stress induction (Trier Social Stress Test - Group version), and post-stressor recovery periods. The VAS-stress scale ranges from low stress to high stress, with higher scores indicating greater perceived stress. |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORNicole Stevens, PhD
DoTERRA International LLC.
Outcome results
None listed