Kimchi Powder on Gut Health

NCT07749092 | Recruiting

• 1 other identifier: 12-2025-021
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

The investigators will conduct a randomized, double-blind, placebo-controlled study to investigate the effects of Kimchi powder supplementation on gut health in adults with diarrhea-predominant irritable bowel syndrome (IBS-D) for 8 weeks.

Conditions

Irritable Bowel Syndrome - Diarrhoea

Keywords

Kimchi; Irritable bowel syndrome - Diarrhea; Gut microbiome; Fermented food

Outcome Measures

Primary Outcomes (1)

• Change in IBS Severity Scoring System (IBS-SSS) total score

  The IBS Severity Scoring System (IBS-SSS) consists of five items assessing severity of abdominal pain, frequency of abdominal pain, severity of abdominal distension, dissatisfaction with bowel habits, and interference with quality of life. Each item is scored on a 100-point visual analogue scale, giving a total score ranging from 0 to 500. Higher scores indicate more severe symptoms; scores below 75 indicate remission, 75 to 175 mild, 175 to 300 moderate, and above 300 severe irritable bowel syndrome. Change is calculated as the Week 8 value minus the baseline value, with a negative change indicating improvement.

  Baseline (Day 0) and Week 8 (Day 56 +/- 7)

Secondary Outcomes (10)

• Change in stool form measured by the Bristol Stool Form Scale

  Baseline (Day 0) and Week 8 (Day 56 +/- 7)

• Change in Irritable Bowel Syndrome Quality of Life (IBS-QOL) score

  Baseline (Day 0), Week 3 (Day 21 +/- 7), and Week 8 (Day 56 +/- 7)

• Change in Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS) score

  Baseline (Day 0) and Week 8 (Day 56 +/- 7)

• Change in defecation symptom assessment (frequency of diarrhea)

  Baseline (Day 0) and Week 8 (Day 56 +/- 7)

• Change in serum interleukin-1 beta (IL-1beta) concentration

  Baseline (Day 0) and Week 8 (Day 56 +/- 7)

Study Arms (2)

This group takes Kimchi power for 8 weeks.

EXPERIMENTAL

Participants take capsules containing kimchi powder, 3 capsules three times daily after breakfast, lunch, and dinner with water, for 8 weeks (56 days). Total daily intake is 3,600 mg/day (400 mg x 9 capsules), corresponding to 3,000 mg/day of kimchi powder.

Dietary Supplement: Kimchi power

This group takes placebo power for 8 weeks.

PLACEBO COMPARATOR

Participants take placebo capsules identical in appearance to the test product, containing lactose and other excipients, 3 capsules three times daily after breakfast, lunch, and dinner with water, for 8 weeks (56 days). Total daily intake is 3,600 mg/day (400 mg x 9 capsules).

Dietary Supplement: Placebo

Interventions

Kimchi power DIETARY_SUPPLEMENT

Kimchi powder in capsule form, 3,000 mg/day of kimchi powder (total 3,600 mg/day as capsules), taken orally in three divided doses after meals for 8 weeks.

This group takes Kimchi power for 8 weeks.

Placebo DIETARY_SUPPLEMENT

Placebo capsules identical in appearance and packaging to the test product, containing lactose and other excipients, total 3,600 mg/day, taken orally in three divided doses after meals for 8 weeks.

This group takes placebo power for 8 weeks.

Eligibility Criteria

• Age: 20 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults, male or female, aged 20 to 70 years
• Body mass index of 25 kg/m2 or more and less than 30 kg/m2
• Meeting the Rome IV criteria for diarrhea-predominant irritable bowel syndrome (IBS-D), defined as Bristol Stool Form Scale type 6 or 7 in 25% or more of bowel movements from 2 weeks before screening through the day of the screening visit
• No inflammatory bowel disease or malignancy
• Provided written agreement to refrain from consuming kimchi-containing foods for the duration of the study (approximately 2 months)

You may not qualify if:

• Drug-induced constipation
• Constipation secondary to another condition, such as diabetes mellitus or thyroid disease
• History of intra-abdominal surgery other than appendectomy (including gastrectomy, gastric bypass, gallbladder or biliary tract surgery, pancreatectomy, bowel resection with particular reference to the ileum, and colorectal surgery or insertion procedures)
• Uncontrolled hypertension (resting blood pressure 160/100 mmHg or higher)
• Uncontrolled diabetes mellitus (fasting blood glucose 160 mg/dL or higher)
• Uncontrolled hypothyroidism or hyperthyroidism
• AST or ALT concentration 3 times or more the upper limit of the reference range of the testing laboratory
• Creatinine concentration 2 times or more the upper limit of the reference range of the testing laboratory
• Severe cardiovascular or cerebrovascular disease or malignancy within the previous 6 months
• Psychiatric disorder such as severe affective disorder, schizophrenia, or substance use disorder, or current use of related psychiatric medication (intermittent use for sleep disturbance is permitted)
• Severe alcohol use disorder
• Heavy smoking (20 cigarettes per day or more)
• Hypersensitivity to the main ingredient or components of the study food
• Severe gastrointestinal symptoms such as heartburn or dyspepsia
• Use of medications or foods that may affect the study results, including kimchi and probiotics

Sponsors & Collaborators

• Pusan National University Yangsan Hospital: lead

Study Sites (1)

Pusan National University Yangsan Hospital

Yangsan, 50612, South Korea

RECRUITING

Study Officials

• Sang Yeoup Lee, MD, PhD

  Pusan National University Yangsan Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Professor

CONTACT

+82-55-360-2860; drsaylee@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: August 1, 2026
• First Posted: August 6, 2026
• Study Start: August 3, 2026
• Primary Completion (Estimated): December 30, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: August 6, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

KR (1)