NCT Number: NCT07134543
Using the Smart Underwear Device to Determine a Baseline of Flatus Activity Normalized to Fiber Intake
The goal of this observational study is to quantify the typical frequency of flatulence in healthy adults, normalized by fiber intake, using the Smart Underwear device. The study will enroll a maximum of 500 adults across the United States who will wear the device for three consecutive days while continuing their usual daily activities.
The main questions it aims to answer are:
* What is the average frequency of flatus events in a general adult population? * How does dietary fiber intake influence flatus frequency and microbiome activity?
Researchers will collect gas sensor data from the Smart Underwear device alongside dietary information logged in a mobile app to assess the relationship between diet and microbiome activity.
Participants will:
* Complete an online eligibility survey, consent form, and background questionnaire. * Wear the Smart Underwear device for at least 12 hours per day for three consecutive days. * Log all meals with photos using a custom smartphone app. * Complete a short post-wear survey about device comfort and usability.
All study procedures will be conducted remotely. Data will be analyzed in de-identified form to evaluate baseline flatulence patterns, normalized to fiber intake, in the general adult population.
Interested in participating?
Request InfoKey information
Age range
18 year and older
Sex eligibility
All sexes
Study type
Observational
Primary location
Bioscience Research Building, College Park, Maryland, United States
Who can participate
Healthy volunteers accepted: Yes
Only the study team can determine whether someone qualifies for participation.
Inclusion criteria
- 18 years old or older
- Lives in the US
- Is not pregnant or lactating
- Is willing to wear the Smart Underwear device as instructed in the study procedures
Exclusion criteria
- Younger than 18 years old
- Lives outside the US
- Is pregnant or lactating
- Is not willing to wear the Smart Underwear device as instructed in the study procedures
Treatment and study plan
Primary outcomes
-
Microbiome Activity Index
Time frame: 12 hours each day for 3 days
The Microbiome Activity Index is a composite measure reflecting gut microbiome activity, calculated from both flatus frequency and hydrogen gas concentration. The index uses the absolute value of the first derivative of the hydrogen sensor signal to better capture flatus intensity, reduce baseline noise, and mitigate sensor saturation at high hydrogen levels. This composite approach ensures a more accurate representation of gut microbiome activity than relying on flatus count or hydrogen concentration alone. Data are collected using a wearable device ("Smart Underwear") and uploaded to the Human Flatus Atlas app.
Secondary outcomes
-
Total flatus count
Time frame: 12 hours each day for 3 days
The total number of flatus events detected by the wearable device. Detection is based on hydrogen gas concentration changes and signal rate-of-change analysis.
-
Flatus Per Hour
Time frame: 12 hours each day for 3 days
The rate of flatus events normalized per hour, calculated from the total number of events and the total monitored time.
-
Microbiome Activity Index Comparative Score
Time frame: 12 hours each day for 3 days
A relative score comparing the participant's Microbiome Activity Index to aggregated anonymized results from other individuals in the Human Flatus Atlas study. Presented as a percentile rank or standardized score.
-
Fiber-Normalized Flatus Frequency
Time frame: 12 hours each day for 3 days
The participant's flatus frequency (events/day) normalized by self-reported dietary fiber intake (grams/day). Normalization will allow assessment of typical adult flatulence frequency in relation to fiber consumption.
Study contacts
Contact information is provided by the study sponsor or research team.
Sponsors and collaborators
Lead sponsor
University of Maryland, College Park
Other
Registry information
Important dates
- Study start
- 2025
- Primary completion
- 2026
- Study completion
- 2026
- First posted
- Aug 21, 2025
- Registry last updated
- Dec 23, 2025
OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.
View the official ClinicalTrials.gov record (opens in a new tab)This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.