Healthy AdultsPhase 2NCT07163819
Effect of Probiotic Intervention on Travel-Related Health Conditions During Short-Term Overseas Travel
A Phase 2 study testing Probiotic in people with Healthy Adults, run by Universiti Sains Malaysia at 2 sites in 2 countries.
Trial summary
International travel disrupts gut health through dietary changes, microbial exposure, and stress, often causing gastrointestinal symptoms like traveler's diarrhea and sleep disturbances. These shifts may increase antibiotic resistance risks. Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy Adults
- What is being tested?
- Probiotic
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 46 participants
- Where
- 2 sitesin 2 countries
- Study dates
- 31 Jul 2025to 31 Dec 2025
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
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
- Generally healthy adults
- Scheduled to undertake a short-term round trip (less than 7 days) to abroad
- Able to complete study procedures
- Willing to take intervention products
Who cannot join
- Use of antibiotics, probiotics, hormones, immunosuppressants, biologics or JAK inhibitors within four weeks prior to study
- Chronic or severe systemic diseases (including cardiovascular, hepatic, renal, malignant or psychiatric disorders)
- Uncontrolled parasitic infections
- Long-term use of corticosteroids, growth hormone, vitamin B12, lysine or inositol
- Major surgery within one month
- Allergy to probiotic components
- Other conditions deemed inappropriate by investigators
Trial locations and contacts
2 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
2 sites in 2 countries
China1 site, 1 recruiting
- Recruiting
Tsinghua University Science and Technology
Haidian, Beijing Municipality, 100080
Ai Zhou, Ph.D., 8662785846, ahz@tsinghua.edu.cn
Min Tze Liong, Ph.D., 6046532114, mintze.liong@usm.my
Malaysia1 site, 1 recruiting
- Not yet recruiting
Universiti Sains Malaysia
George Town, Pulau Pinang, 11800
Min Tze Liong, Ph.D., 6046532114, mintze.liong@usm.my
Ai Jie, Ph.D., peanut.yuan@diprobio.com
About this study
International travel disrupts gut health through dietary changes, microbial exposure, and stress, often causing gastrointestinal symptoms like traveler's diarrhea and sleep disturbances. These shifts may increase antibiotic resistance risks. Probiotics may help stabilize gut microbiota and improve well-being during travel. This randomized, double-blind, placebo-controlled trial investigated whether probiotic supplementation mitigates gut microbiota perturbations, gastrointestinal symptoms, and sleep issues in adults traveling abroad. The investigators also assessed changes in anxiety, well-being, gut immunity, microbial function, and antibiotic resistance genes.
Read the detailed description
International travel exposes individuals to abrupt changes in diet, water sources, microbial exposures, sleep schedules, and psychological stress. These factors often perturb the gut microbiota and influence host health outcomes. Studies have reported significant fluctuations in gut microbiota among travelers, even in those without diarrheal symptoms, with marked shifts in microbiome composition during short-term travel. Such perturbations are frequently accompanied by gastrointestinal symptoms and reduced well-being, highlighting the need for strategies to maintain gut homeostasis during travel.
Traveler's diarrhea remains one of the most common travel-related illnesses, with incidence rates varying from 30-70% depending on destination and season. Gastrointestinal discomfort during travel extends beyond diarrhea to include abdominal pain, abnormal gut transit, loose stools, and other non-diarrheal symptoms. These issues can significantly impact travel comfort and enjoyment.
International travel has also been associated with increased risk of acquiring antimicrobial-resistant organisms and genes, posing concerns for both individual and public health. The gut environment facilitates the selection and exchange of antibiotic resistance determinants, with studies showing increased abundance and diversity of antimicrobial resistance genes following travel.
Sleep disturbances represent another significant challenge during travel, arising from time zone changes and adaptation to new environments. These disruptions can profoundly affect well-being given sleep's critical role in health. The relationship between sleep and gut microbiota through the microbiome-gut-brain axis suggests that sleep disturbances during travel may contribute to gastrointestinal vulnerability through neuroendocrine, immune, and metabolic pathways.
Probiotics, defined as live microorganisms that confer health benefits when administered in adequate amounts, represent a potential intervention strategy. Evidence suggests probiotics enhance colonization resistance against pathogens, modulate immune responses, strengthen epithelial barrier integrity, and generate beneficial metabolites. Beyond gastrointestinal benefits, probiotics may influence systemic inflammation, lipid metabolism, and mental health outcomes through the gut-brain axis. While some evidence supports their role in reducing gastrointestinal transit time and constipation symptoms, as well as modest protection against traveler's diarrhea, robust data specifically regarding travel-related probiotic interventions remains limited.
The investigators conducted a randomized, double-blind, placebo-controlled trial in healthy adults undertaking short-term international travel. The study aimed to determine whether daily probiotic supplementation attenuates travel-associated perturbations in gut microbiota composition and diversity, while assessing concurrent changes in gastrointestinal symptoms, sleep quality, anxiety, and subjective well-being using validated instruments. Functional outcomes included assessment of specific microbial species, secretory immunoglobulin A, vitamin-related indices, antibiotic resistance genes, and metabolic pathway analyses to provide mechanistic insights. The investigators hypothesized that probiotic supplementation would stabilize the gut microbiota, enrich beneficial taxa and functions, and improve both gastrointestinal comfort and psychological outcomes compared with placebo.
- Conditions
- Healthy Adults
- Being tested
- Probiotic, Placebo
- Keywords
- probiotic, international travel
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ProbioticOther
Daily 6-drops of Bifidobacterium longum subsp. infantis M-63, B. breve M-16V, and B. longum BB536 in non-GMO corn starch as excipient, in medium-chain triglyceride oil (1.5 × 109 CFU/day)
PlaceboOther
Daily 6-drops of non-GMO corn starch in medium-chain triglyceride oil
| Study group | Role | What they receive |
|---|---|---|
| Placebo | Placebo comparator | Daily 6-drops of non-GMO corn starch in medium-chain triglyceride oil Receives: Other: Placebo |
| Probiotic | Experimental | Daily 6-drops of Bifidobacterium longum subsp. infantis M-63, B. breve M-16V, and B. longum BB536 in non-GMO corn starch as excipient, in medium-chain triglyceride oil (1.5 × 109 CFU/day) Receives: Other: Probiotic |
What is being measured
The primary outcome is the main question the study is designed to answer.
Microbiota profiles of fecal samples in generally healthy adults upon administration of probiotic as assessed via metagenomics sequencing
Differences in microbiota abundance in fecal sample of generally healthy adults upon administration o probiotic compared to placebo
Measured: 7 days
Secondary outcomes (5)
Respiratory symptoms duration and frequency in generally healthy adults upon administration of probiotic as assessed using questionnaire
Changes in duration and frequency of respiratory illnesses symptoms from generally healthy adults on probiotic or placebo after 7-days, via the use of standard clinical assessment questionnaire, scale 0-3 where higher scores indicate more severe symptoms.
Measured: 7 days
Gastrointestinal symptoms in generally healthy adults upon administration of probiotic as assessed using questionnaire
Differences in duration and frequency of gastrointestinal symptoms upon administration of probiotic compared to placebo via the use of standard clinical assessment questionnaire, scale 0-3 where higher scores indicate more severe symptoms.
Measured: 7 days
Allergy symptoms in generally healthy adults upon administration of probiotic as assessed using questionnaire
Differences in duration and frequency of allergy symptoms upon administration of probiotic compared to placebo via the use of standard clinical assessment questionnaire, scale 0-3 where higher scores indicate more severe symptoms.
Measured: 7 days
Gastrointestinal metabolites in generally healthy adults upon administration of probiotic as assessed using LC-MS
Differences in concentrations of gastrointestinal metabolites upon administration of probiotic compared to placebo
Measured: 7 days
Quality of life in generally healthy adults upon administration of probiotic as assessed using questionnaire
Differences in quality of life via the use of questionnaires such as anxiety (GAD-7, scale 0-3 where higher scores indicate more severe outcomes), sleep (PSQI, scale 0-3 where higher scores indicate more severe outcomes) and well-being (WHO-5, scale 0-5 where higher scores indicate better outcomes) upon administration of probiotic compared to placebo.
Measured: 7 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Sep 2025
- Study start31 Jul 2025
- Primary completion31 Dec 2025 (estimated)
- Study completion31 Dec 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Healthy AdultsStudies 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 2
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 46 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universiti Sains Malaysia
- Sponsor type
- University, hospital or other
- Collaborators
- Tsinghua University Science and Technology
- Responsible party
- Principal investigator, Min-Tze LIONG, Universiti Sains Malaysia
- Investigators
- Ai Zhou, Ph.D., Principal investigator, Tsinghua University Science and Technology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07163819
- Sponsor's protocol ID
- THU-01-2025-1007
- Status last verified
- Sep 2025
- First submitted
- 1 Sep 2025
- Last updated
- 17 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Wang L, Yu Y, Shen X, Li X, Wang D, Zhai Y, Jiang W, Zhao W, Yu Q, Liong MT, Chen D, Zhao A. Bifidobacterium supplementation maintains gut microbiota stability and enhances well-being during short-term travel. Front Nutr. 2026 Feb 12;13:1724829. doi: 10.3389/fnut.2026.1724829. eCollection 2026.
PubMed 41769651
Study at a glance
From the registry record, last updated by the sponsor on 17 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Probiotic Intervention on Travel-Related Health Conditions During Short-Term Overseas Travel
- ClinicalTrials.gov ID
- NCT07163819
- Acronym / sponsor ID
- THU-01-2025-1007
- Conditions
- Healthy Adults
- Keywords
- probiotic, international travel
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 46 participants (estimated)
- Lead sponsor
- Universiti Sains MalaysiaUniversity, hospital or other
- Collaborators
- Tsinghua University Science and Technology
- Study start
- 31 Jul 2025 (actual)
- Primary completion
- 31 Dec 2025 (estimated)
- Study completion
- 31 Dec 2025 (estimated)
- First posted
- 9 Sep 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.
International travel disrupts gut health through dietary changes, microbial exposure, and stress, often causing gastrointestinal symptoms like traveler's diarrhea and sleep disturbances. These shifts may increase antibiotic resistance risks. Probiotics may help stabilize gut microbiota and improve well-being during travel. This randomized, double-blind, placebo-controlled trial investigated whether probiotic supplementation mitigates gut microbiota perturbations, gastrointestinal symptoms, and sleep issues in adults traveling abroad. The investigators also assessed changes in anxiety, well-being, gut immunity, microbial function, and antibiotic resistance genes.
Detailed description
International travel exposes individuals to abrupt changes in diet, water sources, microbial exposures, sleep schedules, and psychological stress. These factors often perturb the gut microbiota and influence host health outcomes. Studies have reported significant fluctuations in gut microbiota among travelers, even in those without diarrheal symptoms, with marked shifts in microbiome composition during short-term travel. Such perturbations are frequently accompanied by gastrointestinal symptoms and reduced well-being, highlighting the need for strategies to maintain gut homeostasis during travel.
Traveler's diarrhea remains one of the most common travel-related illnesses, with incidence rates varying from 30-70% depending on destination and season. Gastrointestinal discomfort during travel extends beyond diarrhea to include abdominal pain, abnormal gut transit, loose stools, and other non-diarrheal symptoms. These issues can significantly impact travel comfort and enjoyment.
International travel has also been associated with increased risk of acquiring antimicrobial-resistant organisms and genes, posing concerns for both individual and public health. The gut environment facilitates the selection and exchange of antibiotic resistance determinants, with studies showing increased abundance and diversity of antimicrobial resistance genes following travel.
Sleep disturbances represent another significant challenge during travel, arising from time zone changes and adaptation to new environments. These disruptions can profoundly affect well-being given sleep's critical role in health. The relationship between sleep and gut microbiota through the microbiome-gut-brain axis suggests that sleep disturbances during travel may contribute to gastrointestinal vulnerability through neuroendocrine, immune, and metabolic pathways.
Probiotics, defined as live microorganisms that confer health benefits when administered in adequate amounts, represent a potential intervention strategy. Evidence suggests probiotics enhance colonization resistance against pathogens, modulate immune responses, strengthen epithelial barrier integrity, and generate beneficial metabolites. Beyond gastrointestinal benefits, probiotics may influence systemic inflammation, lipid metabolism, and mental health outcomes through the gut-brain axis. While some evidence supports their role in reducing gastrointestinal transit time and constipation symptoms, as well as modest protection against traveler's diarrhea, robust data specifically regarding travel-related probiotic interventions remains limited.
The investigators conducted a randomized, double-blind, placebo-controlled trial in healthy adults undertaking short-term international travel. The study aimed to determine whether daily probiotic supplementation attenuates travel-associated perturbations in gut microbiota composition and diversity, while assessing concurrent changes in gastrointestinal symptoms, sleep quality, anxiety, and subjective well-being using validated instruments. Functional outcomes included assessment of specific microbial species, secretory immunoglobulin A, vitamin-related indices, antibiotic resistance genes, and metabolic pathway analyses to provide mechanistic insights. The investigators hypothesized that probiotic supplementation would stabilize the gut microbiota, enrich beneficial taxa and functions, and improve both gastrointestinal comfort and psychological outcomes compared with placebo.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Placebo | Placebo comparator | Other: PlaceboDaily 6-drops of non-GMO corn starch in medium-chain triglyceride oil |
| Probiotic | Experimental | Other: ProbioticDaily 6-drops of Bifidobacterium longum subsp. infantis M-63, B. breve M-16V, and B. longum BB536 in non-GMO corn starch as excipient, in medium-chain triglyceride oil (1.5 × 109 CFU/day) |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Generally healthy adults
- Scheduled to undertake a short-term round trip (less than 7 days) to abroad
- Able to complete study procedures
- Willing to take intervention products
Key exclusion criteria (7 listed)
- Use of antibiotics, probiotics, hormones, immunosuppressants, biologics or JAK inhibitors within four weeks prior to study
- Chronic or severe systemic diseases (including cardiovascular, hepatic, renal, malignant or psychiatric disorders)
- Uncontrolled parasitic infections
- Long-term use of corticosteroids, growth hormone, vitamin B12, lysine or inositol
- Major surgery within one 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 |
|---|---|---|
| ProbioticDaily 6-drops of Bifidobacterium longum subsp. infantis M-63, B. breve M-16V, and B. longum BB536 in non-GMO corn starch as excipient, in medium-chain triglyceride oil (1.5 × 109 CFU/day) | Other | Probiotic |
| PlaceboDaily 6-drops of non-GMO corn starch in medium-chain triglyceride oil | Other | Placebo |
Primary outcome
Microbiota profiles of fecal samples in generally healthy adults upon administration of probiotic as assessed via metagenomics sequencing
Time frame: 7 days
Differences in microbiota abundance in fecal sample of generally healthy adults upon administration o probiotic compared to placebo
5 secondary outcomes
Respiratory symptoms duration and frequency in generally healthy adults upon administration of probiotic as assessed using questionnaire
Time frame: 7 days
Gastrointestinal symptoms in generally healthy adults upon administration of probiotic as assessed using questionnaire
Time frame: 7 days
Allergy symptoms in generally healthy adults upon administration of probiotic as assessed using questionnaire
Time frame: 7 days
Gastrointestinal metabolites in generally healthy adults upon administration of probiotic as assessed using LC-MS
Time frame: 7 days
Quality of life in generally healthy adults upon administration of probiotic as assessed using questionnaire
Time frame: 7 days
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Sep 2025.
- Derived from this study: PubMed 41769651Wang L, Yu Y, Shen X, Li X, Wang D, Zhai Y, Jiang W, Zhao W, Yu Q, Liong MT, Chen D, Zhao A. Bifidobacterium supplementation maintains gut microbiota stability and enhances well-being during short-term travel. Front Nutr. 2026 Feb 12;13:1724829. doi: 10.3389/fnut.2026.1724829. eCollection 2026.
- Individual participant dataSharing planned: No
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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.
Ai Zhou, Ph.D. principal investigator
Tsinghua University Science and Technology
2 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Probiotic in people with Healthy Adults, run by Universiti Sains Malaysia at 2 sites in 2 countries.
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 4 inclusion and 7 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: looking for participants now, as of the sponsor's last update on 17 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in China, Malaysia. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Min Tze Liong, Ph.D. (6046532114, mintze.liong@usm.my), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Microbiota profiles of fecal samples in generally healthy adults upon administration of probiotic as assessed via metagenomics sequencing (time frame: 7 days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07163819, which also lists 1 linked publication.
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 17 Sep 2025; AzTrials last refreshed its copy on 8 Nov 2026.