Fermented Vegetable IntakeNCT06883994
Fermented Vegetables and Gut Microbiome Pilot Study
A study testing Fermented vegetable intervention in people with Fermented Vegetable Intake and Fermented Vegetable Acceptability, run by USDA, Western Human Nutrition Research Center at 1 site in United States.
Trial summary
The purpose of this research is to determine the effect of fermented vegetable consumption on LAB abundance and tolerability of the intervention in young healthy people before conducting a full RCT with older participants. Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Fermented Vegetable Intake, Fermented Vegetable Acceptability, Gut Health
- What is being tested?
- Fermented vegetable intervention
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 1 siteUnited States
- Study dates
- 19 Mar 2025to 9 Sep 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Age 18 - 65 years
- BMI 18.5 - 39.9 kg/m2
Who cannot join
- BMI less than 18.5 or greater than 39.9
- Pregnant or breastfeeding
- Allergy or sensitivity to any fruit or vegetable
- Dietary restriction preventing consumption of fermented vegetables
- Consumption of probiotic supplements, foods or drinks in the past month
- Probiotic supplements include any tablets, liquids, powders, chewables or other formulations that provide high-quantity, live probiotic microbes
Show all 42Show fewer
- Probiotic foods and drinks include products labeled as 'probiotic' because they contain live microbes in types and quantities that may confer a health benefit
- Regular consumption, defined as consumption more than once per week in the past two weeks, of live microbe-containing fermented vegetables or cultured dairy products, such as kimchi, refrigerated fermented pickles, traditional (lacto-fermented) sauerkraut, yogurt, or kefir
- In case of less frequent consumption, defer study start such that baseline assessments are completed at least two weeks after last intake
- Unwillingness to abstain from non-study fermented foods and probiotics during the trial
- Uncomfortable with or unwilling to complete stool sample or saliva collections
- Current participation in another interventional research study
- Having fewer than 3 bowel movements per week
- Unmanaged hypertension, defined as blood pressure greater than or equal to 140/90 mmHg
- Current diagnosis of:
- Disease that affects the immune system or causes immune impairment, including HIV/AIDS
- Cancer
- Diabetes
- Asthma with daily medication
- Primary immune deficiency
- Auto-immune disease
- Chronic gastrointestinal disorder (e.g. Crohn's disease, irritable bowel syndrome, colitis, gastric ulcer)
- Chronic kidney disease
- Current use for 2 weeks or longer of:
- Any drug that affects the immune system, such as immunosuppressants, immune modifying drugs, or corticosteroids (e.g. cortisone, prednisone, methylprednisolone)
- Biologics (e.g. Lantus, Remicade, Rituxan, Humira, Herceptin, Avastin, Lucentis, Enbrel)
- GLP-1 agonists, such as semaglutide and tirzepatide.
- Antidiabetic medications, such as Metformin.
- Diuretics, such as Hydrochlorothiazide
- Use of sulfonamides or antimicrobials, including antibiotics, antifungals, antivirals, and antiparasitic medications in the past 3 months
- Use of laxatives in the past 2 weeks
- Currently undergoing cancer treatment with radiation or drugs
- History of gastrointestinal surgery that would impact study outcomes, such as gastric bypass, intestinal resection, surgeries of the liver or pancreas, or removal of part or all of any organ of the GI tract
- Having within the past 2 weeks:
- Diarrheal illness, defined as passing 3 or more abnormally loose or watery stools in a 24-hour period
- Persistent vomiting
- Fever
- Having within the past 3 months:
- Surgery
- Hospitalization
- Having within the past 1 month:
- Colonoscopy
Trial locations and contacts
1 site in 1 country.
United States1 site
USDA Western Human Nutrition Research Center
Davis, California, 95616
About this study
The purpose of this research is to determine the effect of fermented vegetable consumption on LAB abundance and tolerability of the intervention in young healthy people before conducting a full RCT with older participants.
Read the detailed description
The purpose of this research is to determine the tolerability of fermented vegetable consumption and its effect on lactic acid bacteria (LAB) abundance in healthy people. There is evidence from previous studies that eating fermented foods containing live microbes can affect the gut microbiome and gut health, but there is little information on the impact of fermented vegetables, specifically.
This research will expand the limited existing literature on the effect of fermented vegetable intake on LAB abundance, GI symptoms, fecal consistency and frequency.
Specific knowledge will be produced regarding the magnitude and variation in the increase in LAB bacterial load during fermented vegetable consumption and whether one week is sufficient for LAB to pass out of the gastrointestinal tract. The effect of fermented vegetable consumption on total salivary sIgA levels in healthy adults will also be determined.
The study will also produce knowledge on whether symptoms of bloating and flatulence will improve with fermented vegetables. Stool consistency, stool frequency, GI symptoms, blood pressure and product acceptability data will inform the study design for a future randomized controlled trial of the effects of fermented vegetables on gut microbiome composition and function, gut health and immune function.
The impacts of fermented vegetable consumption on the human gut microbiome, intestinal permeability, and GI inflammation will also be determined with in vitro experiments.
- Conditions
- Fermented Vegetable Intake, Fermented Vegetable Acceptability, Gut Health, Gut Microbiome, Gastrointestinal Immune Function, Microbiome
- Being tested
- Fermented vegetable intervention
- Keywords
- Fermented vegetables, Fermented foods, Nutrition, Adults, Immune function, Gastrointestinal (GI) health, Gut microbiome, GI tract
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Fermented vegetable interventionOther
Participants will be provided with reduced-sodium fermented vegetables developed by Dr. Ilenys Pérez-Díaz at the USDA-ARS Food Science and Market Quality and Handling Research Unit. The fermented, refrigerated vegetables have been shown to have Lactiplantibacillus spp. content >10^7 CFU/mL at 21 days shelf-life.
Products are prepared in a Good Manufacturing Practices Facility at North Carolina State University, Department of Food, Bioprocessing, and Nutrition Sciences.
The fermented vegetables will be shipped in coolers on cold packs with temperature indicators to the WHNRC. Participants will be asked to consume two pre-packaged 50g servings of fermented vegetables a day, for a total daily serving of 100g, not to heat the fermented vegetables prior to consumption, to log their consumption and to rate the acceptability of the fermented vegetables. They will be advised to avoid other fermented foods and to otherwise maintain their habitual diet.
| Study group | Role | What they receive |
|---|---|---|
| Fermented vegetable consumption | Experimental | Participants will complete a 1-week baseline with no fermented food intake, followed by a 4-day fermented vegetable intervention, and then a 1-week follow-up period with no fermented food intake. Receives: Other: Fermented vegetable intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Lactic acid bacteria (LAB) cell count in stool
Bacterial DNA extracted from subject stools will be used for quantitative polymerase chain reaction (qPCR) analysis using primers specific for lactic acid bacteria (LAB) in the intervention food, to estimate bacterial cell count per gram of wet stool.
Measured: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Secondary outcomes (4)
GI symptoms
GI symptoms will be measured using a 10-symptom health questionnaire with degree of discomfort ranked in one of four categories: absent, mild, moderate or severe.
Measured: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Stool frequency
Stool frequency will be measured by self-report in stool diaries and summarized by number of bowel movements per day within each study phase.
Measured: Throughout 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Stool consistency
Stool consistency will be measured by self-report in stool diaries, with stool consistency being classified into 1 of 7 categories according to the Bristol Stool Scale.
Measured: Throughout 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Salivary secretory immunoglobulin A
Total salivary secretory immunoglobulin A (sIgA) will be extracted then measured in duplicate by enzyme-linked immunosorbent assay (ELISA)
Measured: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Mar 2025
- Study start19 Mar 2025
- Primary completion9 Sep 2025
- Study completion9 Sep 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Fermented Vegetable IntakeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 24 participants (actual)
Sponsor and investigators
- Lead sponsor
- USDA, Western Human Nutrition Research Center
- Sponsor type
- US federal agency
- Responsible party
- Principal investigator, Bess L Caswell, USDA, Western Human Nutrition Research Center
- Investigators
- Danielle G Lemay, PhD, Principal investigator, USDA, Western Human Nutrition Research CenterBess L Caswell, PhD, Principal investigator, USDA, Western Human Nutrition Research CenterMary E Kable, PhD, Principal investigator, USDA, Western Human Nutrition Research Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06883994
- Sponsor's protocol ID
- FL125
- Other IDs
- USDA 2032-10700-002-000D
- Status last verified
- Sep 2025
- First submitted
- 10 Mar 2025
- Last updated
- 15 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified data will be shared at the time of study publication in accordance with USDA policy.
Study at a glance
From the registry record, last updated by the sponsor on 15 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Fermented Vegetables and Gut Microbiome Pilot Study
- ClinicalTrials.gov ID
- NCT06883994
- Acronym / sponsor ID
- FL125
- Conditions
- Fermented Vegetable Intake, Fermented Vegetable Acceptability, Gut Health, Gut Microbiome, Gastrointestinal Immune Function, Microbiome
- Keywords
- Fermented vegetables, Fermented foods, Nutrition, Adults, Immune function, Gastrointestinal (GI) health, Gut microbiome, GI tract
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 24 participants (actual)
- Lead sponsor
- USDA, Western Human Nutrition Research CenterUS federal agency
- Study start
- 19 Mar 2025 (actual)
- Primary completion
- 9 Sep 2025 (actual)
- Study completion
- 9 Sep 2025 (actual)
- First posted
- 19 Mar 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this research is to determine the effect of fermented vegetable consumption on LAB abundance and tolerability of the intervention in young healthy people before conducting a full RCT with older participants.
Detailed description
The purpose of this research is to determine the tolerability of fermented vegetable consumption and its effect on lactic acid bacteria (LAB) abundance in healthy people. There is evidence from previous studies that eating fermented foods containing live microbes can affect the gut microbiome and gut health, but there is little information on the impact of fermented vegetables, specifically.
This research will expand the limited existing literature on the effect of fermented vegetable intake on LAB abundance, GI symptoms, fecal consistency and frequency.
Specific knowledge will be produced regarding the magnitude and variation in the increase in LAB bacterial load during fermented vegetable consumption and whether one week is sufficient for LAB to pass out of the gastrointestinal tract. The effect of fermented vegetable consumption on total salivary sIgA levels in healthy adults will also be determined.
The study will also produce knowledge on whether symptoms of bloating and flatulence will improve with fermented vegetables. Stool consistency, stool frequency, GI symptoms, blood pressure and product acceptability data will inform the study design for a future randomized controlled trial of the effects of fermented vegetables on gut microbiome composition and function, gut health and immune function.
The impacts of fermented vegetable consumption on the human gut microbiome, intestinal permeability, and GI inflammation will also be determined with in vitro experiments.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Fermented vegetable consumption | Experimental | Other: Fermented vegetable interventionParticipants will complete a 1-week baseline with no fermented food intake, followed by a 4-day fermented vegetable intervention, and then a 1-week follow-up period with no fermented food intake. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Age 18 - 65 years
- BMI 18.5 - 39.9 kg/m2
Key exclusion criteria (42 listed)
- BMI less than 18.5 or greater than 39.9
- Pregnant or breastfeeding
- Allergy or sensitivity to any fruit or vegetable
- Dietary restriction preventing consumption of fermented vegetables
- Consumption of probiotic supplements, foods or drinks in the past month
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Fermented vegetable interventionParticipants will be provided with reduced-sodium fermented vegetables developed by Dr. Ilenys Pérez-Díaz at the USDA-ARS Food Science and Market Quality and Handling Research Unit. The fermented, refrigerated vegetables have been shown to have Lactiplantibacillus spp. content >10^7 CFU/mL at 21 days shelf-life. Products are prepared in a Good Manufacturing Practices Facility at North Carolina State University, Department of Food, Bioprocessing, and Nutrition Sciences. The fermented vegetables will be shipped in coolers on cold packs with temperature indicators to the WHNRC. Participants will be asked to consume two pre-packaged 50g servings of fermented vegetables a day, for a total daily serving of 100g, not to heat the fermented vegetables prior to consumption, to log their consumption and to rate the acceptability of the fermented vegetables. They will be advised to avoid other fermented foods and to otherwise maintain their habitual diet. | Other | Fermented vegetable consumption |
Primary outcome
Lactic acid bacteria (LAB) cell count in stool
Time frame: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Bacterial DNA extracted from subject stools will be used for quantitative polymerase chain reaction (qPCR) analysis using primers specific for lactic acid bacteria (LAB) in the intervention food, to estimate bacterial cell count per gram of wet stool.
4 secondary outcomes
GI symptoms
Time frame: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Stool frequency
Time frame: Throughout 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Stool consistency
Time frame: Throughout 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Salivary secretory immunoglobulin A
Time frame: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Dec 2025.
- Individual participant dataSharing planned: Yes. De-identified data will be shared at the time of study publication in accordance with USDA policy.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Danielle G Lemay, PhD principal investigator
USDA, Western Human Nutrition Research Center
Bess L Caswell, PhD principal investigator
USDA, Western Human Nutrition Research Center
Mary E Kable, PhD principal investigator
USDA, Western Human Nutrition Research Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Fermented vegetable intervention in people with Fermented Vegetable Intake and Fermented Vegetable Acceptability, run by USDA, Western Human Nutrition Research Center at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 42 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 15 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Lactic acid bacteria (LAB) cell count in stool (time frame: At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Dec 2025.