Tryptophan Supplementation to Improve Night Shift Workers' Health

Sponsor

National Yang Ming University (Other)

Overall Status

Completed

CT.gov ID

NCT04505800

Collaborator

(none)

Enrollment

Location

Arms

Actual Duration (Months)

1.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

This randomized cross-over double-blinded trial aims to investigate the health effect of oral l-tryptophan supplementation on workers who rotate night shift work, and to examine the influences of different frequencies and timings of supplementation on the health effects.

Condition or Disease	Intervention/Treatment	Phase
Sleep Mood Burnout Melatonin Deficiency Cortisol Deficiency	Dietary Supplement: Tryptophan supplement Dietary Supplement: Maltose	N/A

Detailed Description

This study aims to investigate the health effect of oral l-tryptophan supplementation on workers who rotate night shift work, and to examine the influences of different frequencies and timings of supplementation on the health effects. Night shift work affects melatonin and cortisol variation, insomnia, mood issues, and metabolic syndrome. Short-term tryptophan supplementation was shown to improve melatonin, sleep quality, and cortisol response to acute stress. Little is known whether a longer term of longer-term tryptophan supplementation would alleviate the health impacts of night shift work. Nevertheless, melatonin and cortisol have their normal circadian patterns. Nothing is known about what temporal structure of tryptophan supplement would maximize its health effects on night shift workers melatonin and cortisol levels. We will conduct a double-blind cross-over randomized controlled trial to examine the benefits of oral tryptophan administration (3g/day, t.i.d.) on night shift workers' health outcomes: melatonin and cortisol levels, sleep quality, moods and work performance. We expect to reveal the health effect of tryptophan supplementation in night shift workers by using sophisticated study design.

Study Design

Study Type:

Interventional

Actual Enrollment :

30 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Triple (Participant, Investigator, Outcomes Assessor)

Primary Purpose:

Prevention

Official Title:

Chrononutrition of Using L-tryptophan Supplementation to Alleviate the Impacts of Night Shift Rotation on Circadian Hormones and Health Outcomes

Actual Study Start Date :

Sep 1, 2019

Actual Primary Completion Date :

Sep 1, 2020

Actual Study Completion Date :

Dec 31, 2020

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Tryptophan supplement Pure L-tryptophan in capsules (500mg/capsule) 3g tryptophan per day (2 capsules, t.i.d.), at 8AM, 4PM, and 0AM (± 1 hour)	Dietary Supplement: Tryptophan supplement Pure L-tryptophan in capsules (500mg/capsule) 3g tryptophan per day (2 capsules, t.i.d.), at 8AM, 4PM, and 0AM (± 1 hour)
Placebo Comparator: Maltose Placebo is maltose powder capsule (500mg/capsule) 3g maltose powder per day (2 capsules, t.i.d.), at 8AM, 4PM, and 0AM (± 1 hour)	Dietary Supplement: Maltose Maltose

Arm

Intervention/Treatment

Experimental: Tryptophan supplement

Pure L-tryptophan in capsules (500mg/capsule) 3g tryptophan per day (2 capsules, t.i.d.), at 8AM, 4PM, and 0AM (± 1 hour)

Dietary Supplement: Tryptophan supplement

Pure L-tryptophan in capsules (500mg/capsule) 3g tryptophan per day (2 capsules, t.i.d.), at 8AM, 4PM, and 0AM (± 1 hour)

Placebo Comparator: Maltose

Placebo is maltose powder capsule (500mg/capsule) 3g maltose powder per day (2 capsules, t.i.d.), at 8AM, 4PM, and 0AM (± 1 hour)

Dietary Supplement: Maltose

Maltose

Outcome Measures

Primary Outcome Measures

Melatonin level in the morning [3 weeks]
Morning (8AM) saliva melatonin level change in the phase
Melatonin level in the afternoon [3 weeks]
Afternoon (4PM) saliva melatonin level change in the phase
Melatonin level at midnight [3 weeks]
Midnight (0AM) saliva melatonin level change in the phase
Cortisol level in the morning [3 weeks]
Morning (8AM) saliva cortisol level change in the phase
Cortisol level in the afternoon [3 weeks]
Afternoon (4PM) saliva cortisol level change in the phase
Cortisol level at midnight [3 weeks]
Midnight (0AM) saliva cortisol level change in the phase

Secondary Outcome Measures

Sleep quality [3 weeks]
Pittsburg Sleep Quality Score (range: 0-21) at the end of the phase. The higher score indicates worse sleep quality
Mood states, depression [3 weeks]
Depression, Anxiety, Stress Scales. Depression score (range 0-42) changes in the phase. The higher score, the more depressed.
Mood states, anxiety [3 weeks]
Depression, Anxiety, Stress Scales. Anxiety score (range 0-42) changes in the phase. The higher score, the more anxious.
Mood states, stress [3 weeks]
Depression, Anxiety, Stress Scales. Stress score (range 0-42) changes in the phase. The higher score, the more stressful.

Eligibility Criteria

Criteria

Ages Eligible for Study:

20 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion criteria:

Age: adults >=20 y/o
Adults who had night shift schedule >1 month before enrollment, and will have similar night shift schedule in the following 2 months. (Eligible night shift schedule: >1 day of evening or night shift in a week)
People who will not have plans to travel to another time zone in the following 2-3 months
People who will plan to stay in the same job position for the following 3 months
People who have no experience in taking tryptophan or melatonin supplement in the past month
Body weight >= 50kg and <=80kg
Non-pregnant, non-breastfeeding, not taking contraceptives
Not under treatment of steroids, not taking sleeping pills