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

• Proportion of days without cold/flu [ Time Frame: over 6 weeks ] [ Designated as safety issue: No ]
  The 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.
• Microbiota Study [ Time Frame: Change in microbiota from pre-baseline to on average week 4 ] [ Designated as safety issue: No ]
  • Microbial diversity measured by DGGE profiling (detect large distortions)
  • qPCR to quantify treatment effects on specific bacteria
• Digestive Health [ Time Frame: Daily for 7 weeks ] [ Designated as safety issue: No ]
  • 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)

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).

• Dietary Supplement: Probiotic- Bifidobacterium Bifidum
  Bifidobacterium bifidum R0071 will be taken as a capsule once daily for 6 weeks.
  Other Names:

  • Bifidobacterium bifidum
  • Supplement A
• Dietary Supplement: Sugar Pill
  Sugar Pill (Sucrose) will be taken as a capsule once daily for 6 weeks.
  Other Name: Sucrose
• Dietary Supplement: Probiotic- Lactobacillus helveticus
  Lactobacillus helveticus R0052 will be taken as a capsule once daily for 6 weeks.
  Other Names:

  • Lactobacillus helveticus
  • Supplement B
• Dietary Supplement: Probiotic- Bifidobacterium longum ss. Infantis R0033
  Bifidobacterium longum ss. Infantis R0033 (Supplement C) will be taken as a capsule once daily for 6 weeks.
  Other Names:

  • Bifidobacterium longum ss. Infantis R0033
  • Supplement C

• Placebo Comparator: Sugar Pill
  Sugar Pill will be taken as a capsule once daily for 6 weeks.
  Intervention: Dietary Supplement: Sugar Pill
• Experimental: Probiotic- Bifidobacterium bifidum
  Bifidobacterium bifidum (Supplement A) will be taken as a capsule once daily for 6 weeks.
  Intervention: Dietary Supplement: Probiotic- Bifidobacterium Bifidum
• Experimental: Probiotic- Lactobacillus helveticus
  Lactobacillus helveticus (Supplement B) will be taken as a capsule once daily for 6 weeks.
  Intervention: Dietary Supplement: Probiotic- Lactobacillus helveticus
• Experimental: Probiotic- Bifidobacterium longum ss. Infantis R0033
  Bifidobacterium longum ss. Infantis R0033 (Supplement C)will be taken as a capsule once daily for 6 weeks.
  Intervention: Dietary Supplement: Probiotic- Bifidobacterium longum ss. Infantis R0033

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.