Essential Oil-Based Product System for Digestive Support

Efficacy and Safety of an Essential Oil-Based Product System for Digestive Support

This study aims to evaluate the efficacy of specific essential oils. Efficacy will be evaluated through changes, if any, to hsCRP, gene expression, and standard hematologic and metabolic parameters, as well as subjective health changes as measured by Gastrointestinal Symptom Rating Scale (GSRS), PROMIS Global Health survey, PROMIS Fatigue Scale, Immune Fitness Item Scale (IFIS), and the Immune Status Questionnaire (ISQ) in healthy volunteers. The main questions it aims to answer are:

1. Do specific essential oils affect gene expression and hematologic and metabolic parameters as measured in blood?
2. How do essential oils affect gut microbiome?
3. How does daily use of specific essential oils affect subjective quality of life and health parameters?
4. Is ingesting and topically applying specific essential oils daily safe, as measured by laboratory tests and adverse events?

Two study products will be used: oil for topical use, supplement for internal use. The two products will be used together and compared to a placebo group. The topical oil contains a blend of ginger essential oil, peppermint essential oil, caraway essential oil, coriander essential oil, and anise essential oil. The supplement contains everything the oil has, plus anise essential oil.

Participants will:

• Be assigned one of the two groups.
• Use the oil topically once each day for 4 weeks.
• Take one supplement in the morning and one in the evening every day for 4 weeks.
• Attend 2 study visits in which they provide blood and urine (females only) samples.
• Complete 2 stool collection/microbiome kits
• Complete surveys and subjective health assessments

Study Overview

• Status: Not yet recruiting
• Conditions: Healthy
• Intervention / Treatment: Dietary supplement: essential oil supplement; Other: Essential Oil; Dietary supplement: Placebo supplement; Other: placebo essential oil

Detailed Description

Digestive function plays a central role in daily comfort, quality of life, and overall well-being, even among generally healthy individuals. Many commercially available products are marketed to support normal digestive processes and gastrointestinal comfort; however, controlled human data evaluating their use under typical conditions in healthy populations remain limited. This study is designed to evaluate the tolerability, feasibility, and potential digestive-related effects of DigestZen when used as directed in a real-world context. DigestZen is a proprietary essential oil blend composed of Ginger, Peppermint, Caraway, Coriander, Anise, and Fennel essential oils, ingredients traditionally used to support digestive comfort and normal gastrointestinal function.

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Nicole Stevens; Phone Number: 8016157200; Email: nstevens@doterra.com
• Study Contact Backup: Name: Russell Osguthorpe; Phone Number: 8016157200; Email: rosguthorpe@doterra.com

Study Locations

• United States
  • Utah
    • Pleasant Grove, Utah, United States, 84062
      • dōTERRA International
      • Contact: Nicole Stevens; Phone Number: 8016157200; Email: nstevens@doterra.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18-45 years old
• Willing to attend 2 study visits at Prime Meridian Health Clinic in Pleasant Grove, Utah
• Willing and able to undergo 2 blood draws over 4 weeks
• Willing to provide urine (females) and stool samples twice over 4 weeks
• Willing to wash out of all internally and topically used essential oils or botanical products for at least 2 weeks prior to starting the study, and willing to maintain the washout for the duration of the study (4 weeks)
• Willing and able to use study products as directed daily for about 4 weeks
• Willing to avoid alcohol, recreational drugs, tobacco, and vaping for the duration of the study
• Willing to track use of study products
• Willing to maintain current sleep, diet, and exercise habits for the duration of the study
• No major diseases under treatment by doctor (Medical Reviewer's discretion)
• No pregnancy within the last 90 days or currently breastfeeding, or possibility of becoming pregnant.
• No allergy to any of the ingredients in the study products
• No regular consumption of the study products within the last 1 month
• No alcohol, recreational drug, tobacco, or vaping use in the past 1 month
• No evidence of medical condition, significant disease or disorder, medication, or surgery within the past 12 months that may, in the judgement of the medical provider, put the participant at risk or affect study results, procedures, or outcomes.
• Not currently or previously participating in another clinical trial within the last 30 calendar days.

Exclusion Criteria:

• Failure to meet all listed inclusion criteria

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dietary supplement and topical oil; Participants take two capsules of the dietary supplement (one capsule in the morning and one in the evening) every day for 4 weeks. Participants will also place 2 mL of the oil on their forearms and stomach once daily at bedtime for 4 weeks.	Dietary supplement: essential oil supplement; Internal use will entail ingesting Hypromellose capsules containing 135 mg essential oil and 365 mg extra virgin oil. The essential oils in the supplement are peppermint, coriander, ginger, caraway, cardamom, fennel, and anise. Participants will be instructed to take one capsule in the morning with food and one capsule in the evening with food, at least 3 hours before bedtime. Placebo will be olive oil capsules of the same size and color.; Other: Essential Oil; Topical use will entail applying the DigestZen oil blend diluted to 10% in fractionated coconut oil using a metered dropper. Participants will be instructed to add 2mL to the skin of the inner forearms and belly area and massage until oil has absorbed. The application will happen once per day at bedtime. Placebo will contain fractionated coconut oil with a diluted single constituent for aroma and food coloring.
Placebo Comparator: Placebo; Participants assigned the placebo study products will follow the same use directions as those in the active group. Placebo topical oil will contain fractionated coconut oil with a diluted single constituent for aroma and food coloring. The placebo supplement group will take a supplement that contains olive oil, and will be the same size and color as the active supplement.	Dietary supplement: Placebo supplement; Placebo will be olive oil capsules of the same size and color as the active capsules.; Other: placebo essential oil; Placebo essential oil will contain fractionated coconut oil with diluted single constituent for aroma and food coloring.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
GSRS	Looking for within- and between treatment changes to Gastrointestinal Symptom Rating Scale (GSRS) from baseline to completion. The GSRS uses a 7-point Likert scale for the 15 questions regarding gastrointestinal symptoms with answers ranging from "No discomfort at all" to "Very severe discomfort." Scores range from 15 to 105, and the total score is the sum of all item scores. Higher scores indicate more severe GI symptoms.	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Albumin (g/dL)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Blood urea nitrogen (BUN) (mg/dL)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Alkaline phosphatase (U/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Alanine transaminase (ALT) (U/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Aspartate aminotransferase (AST) (U/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Calcium (mg/dL)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Chloride (mmol/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Potassium (mmol/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Sodium (mmol/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Total bilirubin (mg/dL)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Total protein (g/dL)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Gene expression	Gene expression analysis refers to a genome-wide quantification of methylation. EPIC850K array will be used for methylation analysis. This represents approximately 900,000 gene locations. The main feature performed is a differential methylation analysis to determine what has significantly changed from one time point to another.	4 weeks
Complete blood count (CBC)	Change from baseline to Day 30 in white blood cell count and differential as measured by complete blood count.	4 weeks
Gut microbiome test	Participants complete stool collection kits. Stool is analyzed for gut microbiome composition (e.g. bacteria %/count/type)	4 weeks
Digestion-associated Quality of Life Questionnaire (DQLQ)	Validated, self-reported scale for the measurement of digestion-associated quality of life outcomes. The DQLQ is a 9-item scale with total scores between 0 and 9. Each item is scored as a percentage 0-100, with 100 representing a score of 1. Higher scores indicate greater dissatisfaction with digestion-associated quality of life outcomes.	4 weeks
PROMIS Global Health survey	Validated, self-reported scale that assesses overall health-related quality of life across physical, mental, and social domains. The PROMIS Global Health Survey (v1.2) is a 10-item scale, with items scored between 1 and 5 each. Higher scores are indicative of a healthier person, with exceptions to the questions related to fatigue where a higher score indicates greater fatigue.	4 weeks
Adverse events	This study will monitor the occurrence and frequency of adverse events and safety, both through participant report and blood chemistry/hematology/pregnancy testing (females).	4 weeks
Creatinine (mg/dL)	Item in comprehensive metabolic panel for safety assessment	4 weeks
Carbon dioxide (mmol/L)	Item in comprehensive metabolic panel for safety assessment	4 weeks

Collaborators and Investigators

• Sponsor: dōTERRA International
• Investigators: Principal Investigator: Nicole Stevens, doTERRA International LLC

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: March 9, 2026
• First Submitted That Met QC Criteria: June 15, 2026
• First Posted (Actual): June 17, 2026

Study Record Updates

• Last Update Posted (Actual): June 17, 2026
• Last Update Submitted That Met QC Criteria: June 15, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: gut microbiome; essential oils; gene expression
• Additional Relevant MeSH Terms: Lipids; Oils; Oils, Volatile
• Other Study ID Numbers: DO-126078-DZS

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No