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The Effect of Probiotics (L. Helveticus, B. Longum, and B. Bifidum) on Immune Function and Digestive Health

The Effect of Probiotics on Immune Function, and Digestive Health in Academically-stressed University Students: A Randomized, Double-blinded, Placebo-controlled Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01709825
Enrollment
583
Registered
2012-10-18
Start date
2012-09-30
Completion date
2013-01-31
Last updated
2015-01-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy

Keywords

probiotics, cold, flu, immune function, microbiota

Brief summary

The purpose of this study is to determine if daily consumption of a probiotic in the period before, during and after academic exams will help maintain digestive and immune health and quality of life of undergraduate students.

Detailed description

A randomized, double-blinded, placebo-controlled trial will be used. Healthy full-time undergraduate students will be recruited from the University of Florida via flyers, emails, announcements, etc. Informed consent will be obtained and the inclusion/exclusion criteria will be reviewed to determine whether a participant qualifies for the study. All participants will be consented for the main six-week intervention and a subgroup (n=50/group) of these students will be consented to provide two stool samples. Participants will provide saliva and stool samples (for the sub-group)during the pre-baseline week and during the week of final exams at approximately week 4. At the randomization visit, height, weight and age will be obtained. Participants will be stratified based on body mass index and randomized via sealed envelopes to one of four groups: Lactobacillus helveticus, Bifidobacterium longum ssp. Infantis, Bifidobacterium bifidum or the placebo (n=145/group). Participants will take the study provided capsule of probiotic or placebo daily for 6 weeks. Participants will receive daily questionnaires via email throughout the prebaseline week and the 6-week intervention. Daily questionnaires will ask about intake of the supplement, cold symptoms, and general health (i.e., new medications, doctor visits). Throughout the study, participants will also be asked to complete weekly questionnaires (inquiring about gastrointestinal symptoms and physical activity) and Quality of Life Questionnaires (administered during pre-baseline, final exam week and week 6 of the study).

Interventions

DIETARY_SUPPLEMENTProbiotic- Bifidobacterium Bifidum

Bifidobacterium bifidum R0071 will be taken as a capsule once daily for 6 weeks.

DIETARY_SUPPLEMENTSugar Pill

Sugar Pill (Sucrose) will be taken as a capsule once daily for 6 weeks.

DIETARY_SUPPLEMENTProbiotic- Lactobacillus helveticus

Lactobacillus helveticus R0052 will be taken as a capsule once daily for 6 weeks.

DIETARY_SUPPLEMENTProbiotic- Bifidobacterium longum ss. Infantis R0033

Bifidobacterium longum ss. Infantis R0033 (Supplement C) will be taken as a capsule once daily for 6 weeks.

Sponsors

Lallemand Human Nutrition
CollaboratorUNKNOWN
University of Florida
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

To participate in the study you must: * be 18 years of age or older. * be a healthy full-time undergraduate at the University of Florida. * be willing to complete daily questionnaires form via computer. * be willing to discontinue any immune-enhancing dietary supplements (e.g., prebiotics and fiber supplements, probiotics, echinacea, fish oil, vitamin E \>400% of the RDA or \>60 mg/day). * be willing to take the probiotic capsule daily of 6 weeks. * have had at least one cold in the last 12 months. * have at least 1 final during the scheduled exam week. * have daily access to the Internet.

Exclusion criteria

To participate in the study you must NOT: * be a current smoker. * have chronic allergies involving the upper respiratory tract. * have had immunosuppressive illness or treatment within the last year. * have received antibiotic therapy in the past two months.

Design outcomes

Primary

MeasureTime frameDescription
Microbiota StudyChange in microbiota from pre-baseline to on average week 4* Microbial diversity measured by DGGE profiling (detect large distortions) * qPCR to quantify treatment effects on specific bacteria
Proportion of days without cold/fluover 6 weeksThe intensity of cold/flu symptoms (running/congested nose, stiffness or chills, headache, cough, fatigue, fever, sore throat, achiness, and ear discomfort)will be scored as 0 (not experiencing) to 3 (severe). The symptom intensity from the 9 cold/flu symptoms will be summed to obtain a symptom intensity score. A symptom intensity score of \>6 will be designated as a day of cold. The mean proportion of days without a cold/flu will be compared between each probiotic and the placebo.
Digestive HealthDaily for 7 weeks* Gastrointestinal symptoms (gas, bloating, diarrhea, etc.) * Bowel habits (bowel movement frequency and consistency) * Measures of quality of life (physical functioning, general health, bodily pain, vitality and social functioning)

Secondary

MeasureTime frameDescription
Immune HealthMeasured at pre-baseline and on average week 4* Salivary secretory immunoglobulin A (sIgA) * Fecal sIgA

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 2, 2026