To determine if Bifidobacterium lactis HN109 improves transit time and gastrointestinal symptoms in adults with constipation.

Constipation is a commonly diagnosed gastrointestinal disorder with an estimated prevalence in the general population of 12-19%, which results in lower quality of life and significant healthcare costs to the individual. Almost 9 in 10 physician visits for constipation result in a laxative prescription. Additionally, consumers in the USA and in the United Kingdom spend almost 1 billion dollars annually for over-the-counter laxatives. Chronic constipation is diagnosed almost solely on patient symptoms, which generally includes unsatisfactory defecation due to infrequent stools, difficult stool passage, or both. The cause of chronic constipation is unknown and likely multifactorial with physiological changes, psychological factors, and lifestyle influences identified as possible culprits. Consequently, identification of effective constipation treatments remains a challenge.

The initial management of constipation symptoms is focused on evaluating lifestyle and diet variables as possible culprits. If lifestyle modifications are unsuccessful in alleviating constipation, various medications may be prescribed. In fact, about 50% of adults with constipation are not completely satisfied with available treatments. Consequently, there is a clear need for alternative constipation treatments that are safe, effective, and cost-effective.

Probiotics are live micro-organisms that result in a health benefit for the host when administered in adequate dosages. In recent years, probiotics have been commonly used to alleviate symptoms in a variety of gastrointestinal disorders. It is hypothesized that probiotics help to maintain gut lumen homeostasis by hindering growth of luminal pathogens and restoring the normal flora of the gut. As such, the use of probiotics for the relief of constipation symptoms is very promising. Numerous studies have been published addressing the utility of probiotics for gastrointestinal health including constipation. However, since probiotic efficacy is largely strain-specific, each specific strain must be individually tested in clinical trials.

Given the promising clinical results of probiotics on gastrointestinal health to date, the objective of this clinical trial is to evaluate the safety and effectiveness of 4-week Bifidobacterium lactis HN019 supplementation, in a dose-ranging fashion, on Colonic Transit Time (CTT) and gastrointestinal symptoms in adults with constipation.

Inclusion Criteria:

• 1. Age 18 to 70 years

• 2.Body mass index between 18.5 and 34.9 kg/m2

• 3. Meets the Rome III criteria for functional constipation as follows: (Criteria fulfilled for the last 3 months with symptom onset at least 6 months prior to diagnosis):

  • Must meet 2 or more of the following criteria:

    • Straining during at least 25% of defecations
    • Lumpy or hard stools in at least 25% of defecations
    • Sensation of incomplete evacuation for at least 25% of defecations
    • Sensation of anorectal obstruction/blockage for at least 25% of defecations+ Manual maneuvers to facilitate at least 25% of defecations (e.g., digital evacuation, support of the pelvic floor)
    • Fewer than three defecations per week

  • Loose stools are rarely present without the use of laxatives

  • Insufficient criteria for irritable bowel syndrome

Exclusion Criteria:

• 1.Major gastrointestinal complication (e.g. Crohn's disease, ulcer)
• 2. Prior abdominal surgery that, in the opinion of the investigator, may present a risk for the participant or confound study results
• 3. Clinically significant underlying systemic illness that may preclude the participant's ability to complete the trial or that may confound the study outcomes (e.g. bowel cancer, prostate cancer, terminal illness)
• 4. Daily consumption of probiotics, prebiotics, fermented milk, and/or yogurt within 2 weeks of screening and throughout the trial other than the provided study products
• 5. Laxative use within 48 hours of screening (rescue medication allowed for intolerable symptoms during study)
• 6. Regular use of any drug or dietary supplement known to cause constipation (e.g. iron, opioids, sucralfate, misoprostol, 5-Hydroxytryptamine#-antagonists, antacids with magnesium, calcium or aluminum, antidiarrheal medication, anticholinergic agents, calcium supplements, calcium channel blockers, tricyclic antidepressants or nonsteroidal antiinflammatory drugs), within 1 month before screening.
• 7. Anticipated major dietary or exercise changes during the study
• 8. Systemic steroid use, within 1 month before screening.
• 9. Eating disorder
• 10. Contraindication to dairy products (e.g., intolerance to lactose or any substance in the study product)
• 11. History of alcohol, drug, or medication abuse
• 12. Pregnant or lactating female, or pregnancy planned during study period.