Oral Lactobacillus Reuteri for Skin Barrier Dysfunction in Obesity

A Randomized, Double-blind, Placebo-controlled Clinical Trial to Evaluate the Safety and Efficacy of Oral Lactobacillus Reuteri in Treating Skin Barrier Function Impairment Caused by Obesity.

This clinical trial aims to evaluate the safety and efficacy of oral Lactobacillus reuteri supplementation for treating obesity-induced skin barrier impairment in individuals aged 18-40 with a BMI ≥30. The study focuses on the following questions:

Can oral Lactobacillus reuteri supplementation reduce skin barrier damage (measured by transepidermal water loss/TEWL) in obese participants? Does modulation of gut microbiota with Lactobacillus reuteri impact skin barrier function and systemic inflammation?

Researchers will compare outcomes across two groups:

Intervention Group (Obese): Oral Lactobacillus reuteri capsules. Placebo Control Group (Obese): Oral inactive (heat-killed) Lactobacillus reuteri.

Participant Procedures:

Take daily oral capsules (Lactobacillus reuteri or inactive strain) for 4 weeks.

Undergo non-invasive skin testing (TEWL measurements) at baseline and study completion.

Provide stool and samples for analyses. Complete weekly check-ins to report adverse effects (e.g., gastrointestinal discomfort, skin irritation).

Study Overview

• Status: Not yet recruiting
• Conditions: Microbial Colonization; Skin Barrier to Water Loss
• Intervention / Treatment: Biological: Oral administration of inactive Lactobacillus reuteri group; Biological: Oral Lactobacillus reuteri group

• Study Type: Interventional
• Enrollment (Estimated): 140
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jianglin Zhang; Phone Number: +86 13873143466; Email: zhang.jianglin@szhospital.com
• Study Contact Backup: Name: Changzhou Li; Phone Number: +86 17827062716

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• 1. Meets 2020 WHO BMI classification:
• a. Normal weight (18.5-24.9 kg/m²)
• b. Overweight (25-29.9 kg/m²)
• c. Obesity (≥30 kg/m²)
• 2. Presence of skin barrier impairment (e.g., dryness, erythema, desquamation, or itching)
• 3. Age 18-40 years
• 4. Generally good health (no active systemic diseases)
• 5. Able and willing to provide written informed consent
• 6. No use of oral/topical medications or probiotics within 6 months prior
• 7. No active skin disease or traumatic skin lesions

Exclusion Criteria:

• 1. Known allergy or hypersensitivity to probiotics, placebo, or investigational product
• 2. Active skin disease (e.g., psoriasis, eczema, infection) requiring treatment
• 3. Severe medical conditions:
• a. Cardiopulmonary disease (NYHA class III/IV)
• b. Uncontrolled diabetes (HbA1c >9%)
• c. Autoimmune disorders
• 4. Pregnant or breastfeeding women
• 5. Any condition that may interfere with protocol compliance (per investigator judgement), including:
• a. Inability to understand study procedures
• b. History of poor clinical trial adherence
• 6. Concurrent participation in other interventional trials

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Oral administration of inactive Lactobacillus reuteri group	Biological: Oral administration of inactive Lactobacillus reuteri group; 1×10^11 CFU of inactive Lactobacillus reuteri was given orally once daily for one month
Experimental: Oral Lactobacillus reuteri group	Biological: Oral Lactobacillus reuteri group; 1×10^11 CFU of inactive Lactobacillus reuteri was given orally once daily for one month

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Transepidermal Water Loss (TEWL)	Mean change from baseline in transepidermal water loss (TEWL) on the volar forearm, measured by Tewameter under standardized conditions, reported in grams per square meter per hour (g/m²/h).	Baseline, 1 month

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Fecal Genistein Concentration	Mean change from baseline in the concentration of genistein in fecal samples, quantified using LC-MS/MS, reported in micrograms per gram (μg/g)	Baseline, 1 month
Change in Skin Microbial Alpha Diversity	Mean change from baseline in the Shannon Diversity Index of skin microbiota, assessed via 16S rRNA gene sequencing.	Baseline, 1 month
Change in clinical skin health score	Mean change from baseline in the total score of the Skin Dryness Scoring System, reported as a continuous score (0-8, replace with your scale range).	Baseline, 1 month
Change in Body Mass Index (BMI)	Mean change from baseline in Body Mass Index (BMI), calculated as weight in kilograms divided by height in meters squared, reported in kg/m².	Baseline, 1 month
Change in body weight	Mean change from baseline in total body weight, reported in kilograms (kg).	Baseline, 1 month

Collaborators and Investigators

• Sponsor: Shenzhen People's Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): April 10, 2026
• Primary Completion (Estimated): June 28, 2026
• Study Completion (Estimated): July 30, 2026

Study Registration Dates

• First Submitted: December 3, 2025
• First Submitted That Met QC Criteria: March 31, 2026
• First Posted (Actual): April 6, 2026

Study Record Updates

• Last Update Posted (Actual): April 6, 2026
• Last Update Submitted That Met QC Criteria: March 31, 2026
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Infections; Pathological Conditions, Signs and Symptoms; Communicable Diseases
• Other Study ID Numbers: LL-KY-2025272-02

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