Diet and Microbiome Interactions: Application in Posttraumatic Stress Disorder in Adults Consuming Vegetable Drinks (DMAPS)

July 30, 2025 updated by: Tiffany Weir, Colorado State University

Diet and Microbiome Interactions: Application in Posttraumatic Stress Disorder

The gut microbiome has been shown to impact various facets of human health, including mental health. Studies have shown that populations with more agrarian lifestyles tend to have fewer chronic diseases and mental health issues than industrialized populations. A possible factor in these differences is the loss of co-evolved gut microbial taxa that has occurred with Westernization. This hypothesis, termed "Old Friends Hypothesis" suggests that the loss of certain gut microbes leads to immune dysregulation and increased chronic inflammation that contributes to development of cancers, cardiometabolic diseases and even neuroinflammation that can lead to negative behavioral and mental health outcomes. Other studies have shown that increasing the intake of plant foods may help increase diversity of the microbes in the gut and that this increased diversity could lead to better health outcomes in humans.

The investigators propose to evaluate daily consumption of a drink consisting of a high diversity of plants (30 plant species) for four weeks on the diversity of the gut microbiome, biological signatures of inflammation, quality of life, sleep quality, and PTSD symptoms among persons with a diagnosis of PTSD.

The investigators hypothesize that four weeks of daily consumption of this high plant diversity beverage (30 plant species) will increase gut microbiome ɑ-diversity, reduce markers of systemic inflammation, and improve PTSD symptom severity relative to daily consumption of a beverage containing only three plant species.

Study Overview

Detailed Description

The intervention will be a double-blind parallel arm study that consists of a four-week treatment period where participants will be randomized to either the experimental or control arm of the study.

During this four-week treatment period the participants will consume either a 4 oz beverage consisting of 30 different blended vegetables (high diversity treatment) or a similar control beverage consisting of 4 oz of blended Power Greens mix, containing only 3 different plant species (low diversity F&V treatment).

The participants will be asked to provide 2-day diet records every two weeks throughout the study. Participants will also complete daily bowel movement records using the Bristol Stool Scale (BSS) and collect 3 fecal samples (baseline, mid-point and final) that will be returned to the clinic at scheduled visits. Blood samples and gut, sleep, and mental health questionnaire data will be collected at the beginning and end of the study.

Primary objectives are as follows:

Objective 1: To determine whether consuming a higher number of plant types, thereby increasing exposure to diverse plant-associated microbes, increases gut microbial diversity. Specifically, investigators will use fecal samples from individuals before and after 4-week consumption of a 4 oz beverage made with high (30 different plants) and low botanical diversity (3 different plants) to assess taxonomic richness (CHAO) and diversity (Shannon) using 16s rRNA and metagenomic sequencing approaches.

Objective 2: To determine how differences in plant diversity consumption influence inflammation and immune signatures, specifically plasma hsCRP levels and number/type of circulating T-regulatory cells. hsCRP will be assayed using ELISA and T-cells and other immune cells will be profiled from collected peripheral blood mononucleocytes (PBMCs) via flow cytometry.

Objective 3: To determine whether gut microbial diversity and inflammatory profiles correlate with PTSD symptom severity. PTSD symptoms will be evaluated at each visit using the PCL-5 assessment and changes with treatment as well as correlates with other primary outcome measures will be determined.

Study Type

Interventional

Enrollment (Estimated)

40

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Healthy adults (age 18-65) with a diagnosis of PTSD and a BMI <35. Participants should be willing to follow the study protocols and attend all clinic visits.

Exclusion Criteria:

  • Exclusion criteria include antibiotic use within the previous three months, BMI>35, vegan or vegetarian diet, allergies to any of the foods included in the intervention beverages, an unstable medication regimen, and diagnosis of diseases such as gastrointestinal diseases, cancer, CVD, diabetes or autoimmune disease and pregnancy or breastfeeding. Specific medication use (other than antibiotics) would not disqualify an individual if they have had a stable medication regimen for at least two months prior to beginning the study and remain on their medication for the study duration. However, medication changes or antibiotic use during the study would be a reason for dismissal Additionally, inclusion or exclusion in the study will be determined case-by-case based on self-reported supplement use or if the individual feels they are unable to adhere to the study requirements, which includes consuming beverages daily, providing stool or blood samples, tracking bowel movements and symptoms, and attending scheduled clinic visits.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Supportive Care
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: High plant diversity intervention
30 different vegetables as a 4 oz blended beverage in a mylar pouch.
This is a 4oz shot made from 30 different organic vegetables and packaged in mylar pouches.
Experimental: Low plant diversity intervention group
3 vegetable blend as a 4 oz blended beverage in a mylar pouch.
Blended drink made from 3 organic vegetables (Power Greens mix)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes in self-assessed severity of post-traumatic stress disorder (PTSD) symptoms
Time Frame: From enrollment to the end of the 4-week intervention period.

PTSD Checklist for DSM-5 or the PCL-5 questionnaire.

The PCL-5 is a 20-item self-report measure that assesses the 20 DSM-5 symptoms of PTSD. The PCL-5 has a variety of purposes, including:

Monitoring symptom change during and after treatment Screening individuals for PTSD Making a provisional PTSD diagnosis

A higher score on the PCL-5 indicates a greater level of distress and impairment associated with PTSD symptoms. The total score ranges from 0 to 80, with higher scores reflecting a more severe symptomatology. A total score of 32 or above suggests the presence of clinically significant PTSD symptoms, which may require further assessment and treatment.

From enrollment to the end of the 4-week intervention period.
Gut Microbiota Richness
Time Frame: From enrollment to the end of the 4-week intervention period.
Microbiota richness will be determined by the number of amplicon sequence variants (actual or estimated) in a fecal sample.
From enrollment to the end of the 4-week intervention period.
Gut microbiota diversity
Time Frame: From enrollment to the end of the 4-week intervention period.
The Shannon-Wiener index will be applied to 16s rRNA amplicon sequence variants to determine microbial community diversity within a fecal sample.
From enrollment to the end of the 4-week intervention period.
C-reactive protein in plasma
Time Frame: From enrollment to the end of the 4-week intervention period.
CRP, or C-reactive protein, is a substance produced by the liver in response to inflammation in the body. It is commonly measured in blood using a high sensitivity ELISA test to assess general inflammation levels, helping to identify underlying health issues such as infections, tissue injury, or chronic inflammatory diseases. Elevated levels of CRP are associated with PTSD.
From enrollment to the end of the 4-week intervention period.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Seated Blood Pressure
Time Frame: From enrollment to the end of the 4-week intervention period.
Average of 3 seated brachial blood pressure readings taken in the clinic at each visit.
From enrollment to the end of the 4-week intervention period.
Changes in T-cell populations
Time Frame: From enrollment to the end of the 4-week intervention period.
Using flow cytometry to look at the number and types of T-cells in peripheral blood mononuclear cells can be used to look at changes in immune response and inflammation.
From enrollment to the end of the 4-week intervention period.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Tiffany Weir, PhD, Colorado State University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 25, 2025

Primary Completion (Estimated)

June 30, 2026

Study Completion (Estimated)

July 1, 2026

Study Registration Dates

First Submitted

July 23, 2025

First Submitted That Met QC Criteria

July 30, 2025

First Posted (Actual)

August 6, 2025

Study Record Updates

Last Update Posted (Actual)

August 6, 2025

Last Update Submitted That Met QC Criteria

July 30, 2025

Last Verified

July 1, 2025

More Information

Terms related to this study

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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