Exploring how a dietary supplement affects gut fungi in healthy adults

Understanding the Efficacy of Dietary Supplement on Fungal Mycobiota in Healthy Volunteers: A Pilot Study

Phase 4 Interventional Weill Medical College of Cornell University · NCT06433310

This study is testing if a dietary supplement called L-Phenylalanine can change the types of fungi in the gut of healthy adults.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years and up
SexAll
SponsorWeill Medical College of Cornell University Academic / other
Locations1 site (New York, New York)
Trial IDNCT06433310 on ClinicalTrials.gov

What this trial studies

This pilot study investigates the impact of the dietary supplement L-Phenylalanine on the production of phenylpropionic acid (PPA) and its effects on the fungal populations in the gut microbiome of healthy volunteers. Participants will receive a 14-day supply of L-Phenylalanine capsules, and the study aims to assess how this supplementation influences the diversity of gut mycobiota. The research focuses on understanding the relationship between PPA levels and changes in fungal populations, which may have implications for gut health. The study is designed to fill gaps in knowledge regarding the functional dynamics of gut microbiota and their metabolites.

Who should consider this trial

Good fit: Ideal candidates for this study are healthy adults over the age of 18 without any gastrointestinal conditions.

Not a fit: Patients with a history of gastrointestinal conditions, recent antibiotic or antifungal use, or allergies to L-Phenylalanine will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to new insights into dietary interventions that promote gut health by modulating fungal populations.

How similar studies have performed: While there is existing research on the effects of dietary supplements on gut microbiota, this specific approach focusing on L-Phenylalanine and its antifungal metabolite PPA is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Male or female adults over the age of 18 years

Exclusion Criteria:

* History of a diagnosis of any gastrointestinal condition, such as inflammatory bowel syndrome or disease
* Antibiotic usage within the past two weeks
* Antifungal usage within the past month
* Allergy to L-Phenylalanine or individuals with phenylketonuria (PKU)
* Adults taking medications known to interact with L-phenylalanine supplements, such as Monoamine Oxidase Inhibitors (MOAI), L-DOPA, and some antipsychotic drugs (complete and extensive drug list will be provided to interested participants during screening)
* Pregnant or nursing women

Where this trial is running

New York, New York

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Gut MicrobiomeGut HealthDietary SupplementL-PhenylalaninePhenylpropionic Acid
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.