Probiotics in Occupational Shift Workers


Purpose: To evaluate the influence of probiotic supplementation on body composition and other markers of health in occupational shift-workers.

Participants: Healthy, overweight females (ages 22-55 yrs) who are employed on a shift-working schedule.

Procedures (methods): In a randomized, placebo-controlled intervention, subjects will complete 3 different testing sessions (pre-screening, 1 baseline, 1 post-testing session) as well as a 6-week intervention period. Prescreening will include written informed consent, a health history questionnaire, baseline anthropometric measures, assessment of resting heart rate, and exercise protocol familiarization. Baseline testing will involve body composition, a fasted blood draw, mood surveys, and an exercise treadmill test. Subjects will be randomized to a treatment group (multi-strain probiotic or placebo) for 6 weeks of supplementation that includes 2 electronic contacts, followed by post-testing that will occur in the same fashion as baseline testing.

Condition Intervention
Shift-Work Related Sleep Disturbance Healthy Dietary Supplement: Probiotic Dietary Supplement: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Investigator)
Official Title: Influence of Probiotics on Body Composition and Health in Occupational Shift Workers

Further study details as provided by Abbie Smith-Ryan, PhD, University of North Carolina, Chapel Hill:

Primary Outcome Measures:
  • Visceral Fat [ Time Frame: 6 weeks ]
    measured by ultrasound

Secondary Outcome Measures:
  • Ratio of fat in the abdominal region vs. hip region [ Time Frame: 6 weeks ]
    Measured from dual energy x-ray absorptiometry
  • Body Fat [ Time Frame: 6 weeks ]
    measured from dual energy x-ray absorptiometry
  • Lean body mass [ Time Frame: 6 weeks ]
    measured from dual energy x-ray absorptiometry

Estimated Enrollment: 60
Study Start Date: September 2016
Estimated Study Completion Date: October 2017
Estimated Primary Completion Date: August 2017 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Probiotic
Multi-strain probiotic
Dietary Supplement: Probiotic
Placebo Comparator: Placebo
Maltodextrin placebo
Dietary Supplement: Placebo


Ages Eligible for Study:   22 Years to 55 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Healthy, pre-menopausal women
  • Currently employed on a shift-working (rotating, evening, or night) schedule and has maintained this schedule ≥ 6 months prior to enrollment
  • Participant agrees to maintain usual activity lifestyle
  • Participant has a body mass index of ≥25 kg/m2
  • Participant has provided written and dated informed consent to participate in the study
  • Participant is willing and able to comply with the protocol
  • Participant is apparently healthy and free from disease, as determined by a health history questionnaire
  • Participant agrees to abstain from smoking, caffeine, tobacco, and alcohol before testing days
  • Participant is not currently pregnant and does not desire to become pregnant in the next 8 weeks.

Exclusion Criteria:

  • Having a history of medical or surgical events that may significantly affect the study outcome, including cardiovascular disease, metabolic, renal, hepatic, or musculoskeletal disorders
  • Participant is using, or has used a probiotic supplements within 8 weeks prior to enrollment
  • Participant has lost or gained greater than 8 pounds within the previous 2 months
  • Participant is in, or has participated in another clinical trial within 4 weeks prior to enrollment
  • Participant had or currently has a self-identified eating disorder
  • Participant is pregnant or plans on becoming pregnant
  • Participant has a known allergy or sensitivity to any ingredient in the test product or placebo (determined from health history questionnaire)

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT02951689

Contact: Abbie Smith-Ryan, PhD 919-962-2574    

United States, North Carolina
Applied Physiology Laboratory Recruiting
Chapel Hill, North Carolina, United States, 27599
Contact: Abbie Smith-Ryan, PhD    919-962-2574      
Sponsors and Collaborators
University of North Carolina, Chapel Hill
  More Information

Responsible Party: Abbie Smith-Ryan, PhD, Assistant Professor, University of North Carolina, Chapel Hill Identifier: NCT02951689     History of Changes
Other Study ID Numbers: 16-1397
Study First Received: October 27, 2016
Last Updated: October 30, 2016
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Additional relevant MeSH terms:
Sleep Wake Disorders
Sleep Disorders, Circadian Rhythm
Nervous System Diseases
Mental Disorders
Neurologic Manifestations
Signs and Symptoms
Chronobiology Disorders
Occupational Diseases processed this record on July 19, 2017