Fermented Vegetables and Gut Microbiome Pilot Study

NCT06883994 | Completed

• 2 other identifiers: FL125USDA 2032-10700-002-000D
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief 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.

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

Outcome Measures

Primary Outcomes (1)

• 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.

  At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.

Secondary Outcomes (4)

• GI symptoms

  At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.

• Stool frequency

  Throughout 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.

• Stool consistency

  Throughout 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.

• Salivary secretory immunoglobulin A

  At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.

Other Outcomes (5)

• Acceptability of fermented vegetables

  Throughout 4-day intervention period

• Blood pressure

  At the end of 1-week un-intervened baseline, 4-day intervention and 1-week un-intervened follow-up.

• Gut microbiome composition

  At the end of 1-week un-intervened baseline

Study Arms (1)

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.

Other: Fermented vegetable intervention

Interventions

Fermented vegetable intervention OTHER

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.

Fermented vegetable consumption

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 - 65 years
• BMI 18.5 - 39.9 kg/m2

You may not qualify if:

• 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
• 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:

Sponsors & Collaborators

• USDA, Western Human Nutrition Research Center: lead

Study Sites (1)

USDA Western Human Nutrition Research Center

Davis, California, 95616, United States

Location

Study Officials

• Danielle G Lemay, PhD

  USDA, Western Human Nutrition Research Center

  PRINCIPAL INVESTIGATOR

• Bess L Caswell, PhD

  USDA, Western Human Nutrition Research Center

  PRINCIPAL INVESTIGATOR

• Mary E Kable, PhD

  USDA, Western Human Nutrition Research Center

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: FED
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Research Nutritionist

Study Record Dates

• First Submitted: March 10, 2025
• First Posted: March 19, 2025
• Study Start: March 19, 2025
• Primary Completion: September 9, 2025
• Study Completion: September 9, 2025
• Last Updated: December 15, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• Time Frame: At the time of study publication, de-identified IPD will be permanently archived on a publicly assessible platform.
• Access Criteria: De-identified IPD and supporting information will be publicly available.

Locations

US (1)