Sleep, Mood, Burnout, Melatonin Deficiency, Cortisol Deficiency
Conditions
Keywords
tryptophan, shift work, randomized trial, melatonin, cortisol
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.
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.
Interventions
DIETARY_SUPPLEMENTTryptophan 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_SUPPLEMENTMaltose
Maltose
Sponsors
National Yang Ming Chiao Tung University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to No maximum
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
Exclusion criteria
* diagnosis of renal or liver diseases * diagnosis of Cushing's Disease, Addison's disease * psychiatric diagnosis, such as depression and anxiety disorders * neurological diseases such as dementia, epilepsy, Parkinson's disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cortisol level at midnight | 3 weeks | Midnight (0AM) saliva cortisol 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 |
| Melatonin level in the morning | 3 weeks | Morning (8AM) saliva melatonin level change in the phase |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 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. |
| Sleep quality | 3 weeks | Pittsburg Sleep Quality Score (range: 0-21) at the end of the phase. The higher score indicates worse sleep quality |
Countries
Taiwan
Outcome results
None listed