Food DNA Digestion

Digestion and Transit of Food DNA Through the Human Gut

This pilot study investigates the digestion rate of naturally occurring food DNA through the human digestive tract by detecting residual food DNA in stool samples. The investigators hypothesize that food DNA primarily transits through the digestive system within 24 hours, with maximal detection in stool samples collected the day after ingestion. Previous research has focused on food DNA digestion in human gastric juices, leaving digestion through the entire gut largely unexplored. This study employs a fixed-order within subjects design involving healthy participants. Each participant will submit a baseline stool sample, consume a single dose of a study-specific powdered food (reconstituted in water) differing from their usual diet, and provide the subsequent five stool samples. If five samples are collected in fewer than five days, an additional sample will be obtained on the fifth day post-consumption. The presence and decline of food specific DNA in these samples will be quantified using qPCR, enabling us to determine the digestion rate of food DNA. The study design poses with minimal risk as it non-invasively monitors the natural process of food DNA digestion and transit through stool sample analysis.

Study Overview

• Status: Not yet recruiting
• Conditions: Digestion Rate
• Intervention / Treatment: Dietary supplement: Reconstitutable food powder

Detailed Description

Transit time, the duration for ingested food to travel from ingestion to excretion, is crucial because it influences nutrient absorption, digestion efficiency, gut microbiome composition and the overall health of the gastrointestinal system. While numerous studies have focused on the breakdown of food components such as protein, fat and carbohydrates, the fate of food DNA, an integral part of the cells constituting these foods, remains less explored. Mouse studies indicate that food DNA can be traced in various sections of the digestive tract, with the greatest amount of degradation seen in the stomach. Human studies have supported these reports through showing significant dietary DNA degradation in the stomach and other food components in the stomach not significantly impact the efficiency of this degradation. However, this process is not 100% efficient as residual DNA has been shown to be detectable in stool in levels that are informative for health and epidemiological purposes. How long this residual DNA remains in the digestive tract and as such, the overall transit time and digestion rate for food DNA to be completely depleted from the digestive tract remain an open question.

In this study, the investigators will carry out a behavioral intervention in healthy human participants designed to investigate the transit time of dietary DNA. The design of this study is informed by the PI's previous experience with dietary interventions in human cohorts to better understand the human gut microbiome. This prior experience includes conducting a longitudinal study where samples as well as behavioral and dietary metadata were collected from human volunteers in addition to interventional studies of dietary supplements or fully controlled diets.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Veronica M Carrion; Phone Number: 919-660-7341; Email: vmp19@duke.edu

Study Locations

• United States
  • North Carolina
    • Durham, North Carolina, United States, 27710
      • Medical Sciences Research Building III (MSRB III)

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Above age 18?
• Able to provide stool samples at no risk to the participant?
• Does the participant have card access to the MSRBIII building, and is the participant able to visit this building (at times of the participant's convenience) for the purposes of this study?

Exclusion Criteria:

• Already consume camu camu, maqui or kelp in typical diet?
• Have a history or current diagnosis of irritable bowel syndrome?
• Have a history or current diagnosis of inflammatory bowel disease?
• Have a history or current diagnosis of type 2 diabetes?
• Have a history or current diagnosis of chronic kidney disease with decreased kidney function?
• Have a history or current diagnosis of intestinal obstruction?
• Have a history or current diagnosis of untreated colorectal cancer?
• Has the participant had a colonoscopy within the past month?

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: Stool samples + consumption of powdered food; Each participant will submit a baseline stool sample, consume a single dose of a study-specific powdered food (reconstituted in water) differing from their usual diet, and provide the subsequent five stool samples. If five samples are collected in fewer than five days, an additional sample will be obtained on the fifth day post-consumption

Dietary supplement: Reconstitutable food powder; During the intervention week, participants will be asked take one dose of a reconstitutable food powder provided in a ziplock bag. This powder will be a mix of Gatorade Zero Powder (1 serving) and 1 serving of commercially available powders of either one or all of the following: camu camu, kelp or maqui. The powder mix in the bag will be added to water and drunk by the participant as soon as possible after having a bowel movement (baseline stool sample). Food powders are sourced from reputable companies and are safe for consumption (Gatorade is a wellrecognized brand and available in grocery stores nationally, Navitas Organics provides certified organic, third-party tested plant food powders with fairtrade certification).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Transit time of naturally occurring food DNA through the human digestive tract	Determined by quantifying the presence of food DNA in stool samples over a specified period post-consumption.	Approximately 5-8 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of food DNA depletion	Evaluating the potential implications of the rate of food DNA depletion for nutrient absorption and gut microbiome interactions.	Approximately 5-8 days

Collaborators and Investigators

• Sponsor: Duke University
• Investigators: Principal Investigator: Lawrence David, Duke University

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: November 12, 2024
• First Submitted That Met QC Criteria: November 12, 2024
• First Posted (Actual): November 13, 2024

Study Record Updates

• Last Update Posted (Actual): April 8, 2026
• Last Update Submitted That Met QC Criteria: April 6, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: DNA; gut microbiome; Food; digestive system; digestion; transit time; food DNA digestion
• Other Study ID Numbers: Pro00115407

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