Circadian rhythm disruption (Shift work)
Supplements studied for Circadian rhythm disruption (Shift work).
Overview
SupplementDEX currently indexes Melatonin for circadian rhythm disruption (shift work). See the heatmap and evidence reviews below for the full rating.
Effect graph
Relevant supplements
Relevant supplements sorted by DEX Score.
| Melatonin | ★★★★★ | Low |
Studies
Find individual evidence reviews for supplements sorted by DEX Score.
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MelatoninView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking melatonin by mouth does not seem to make a big difference in how quickly people fall asleep, how efficient their sleep is, or how well they adjust to changing work shifts.
- However, it may slightly increase total sleep time and improve overall sleep quality.
- Studies show melatonin can reduce the time to fall asleep by about 5 to 7 minutes and add a few extra minutes of sleep, but these effects are smaller than those seen with some prescription sleep medicines.
Browse 13 studies·2 meta-analyses
RCT12-week melatonin administration had no effect on diabetes risk markers and fat intake in overweight women night workers2024
A 12-week crossover RCT of 27 overweight female night workers found 3 mg melatonin on days off did not improve fasting glucose, insulin, HbA1c, or HOMA-IR vs placebo.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 3 mg
- Population
- Women
RCTMelatonin supplementation and oxidative DNA damage repair capacity among night shift workers: a randomised placebo-controlled trial2024
A 4-week RCT of 40 night shift workers found melatonin before day sleep associated with a 1.8-fold increase in urinary 8-OHdG excretion, suggesting improved oxidative DNA damage repair capacity.
- Effect
- Benefit
- Duration
- 4 weeks
Systematic reviewEfficacy of Dietary Supplements on Sleep Quality and Daytime Function of Shift Workers: A Systematic Review and Meta-Analysis2022n=917
A systematic review and meta-analysis of 12 RCTs (917 shift workers) found dietary supplements including melatonin significantly improved sleep quality (SMD −0.45) and daytime function (SMD −0.50).
- Effect
- Benefit
- Population
- Pregnant women
- Participants
- 917
Systematic reviewThe efficacy of combined bright light and melatonin therapies on sleep and circadian outcomes: A systematic review2021
A systematic review of 8 studies found combined bright light and melatonin outperformed either alone for circadian phase shifting, with greater benefit in elderly populations than in delayed sleep-wake phase disorder.
- Effect
- Benefit
- Population
- Healthy adults
Systematic reviewEffectiveness of melatonin treatment on circadian rhythm disturbances in dementia. Are there implications for delirium? A systematic review2010n=243
A systematic review of 9 studies (330 dementia patients) found melatonin improved sundowning/agitated behavior and suggested a role in delirium prevention through circadian stabilization.
- Effect
- Benefit
- Population
- Dementia patients
- Participants
- 243
RCTRandomized placebo-controlled field study of the effects of bright light and melatonin in adaptation to night work2007
A field RCT of 17 oil-rig night workers found melatonin (3 mg) and bright light both modestly aided circadian adaptation, with melatonin increasing sleep by 15–20 min/day and reducing sleepiness at work.
- Effect
- Benefit
- Duration
- 4 days
- Dose
- 3 mg/day
MetaEfficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis2006n=651
A meta-analysis of 17 RCTs (651 participants) found no evidence that exogenous melatonin improved sleep onset latency in secondary sleep disorders or sleep restriction conditions, though it appeared safe short-term.
- Effect
- No Benefit
- Participants
- 651
RCTMelatonin treatment of pediatric residents for adaptation to night shift work2005
An RCT of pediatric residents on night shift found 3 mg melatonin significantly reduced omission errors on the Conners Continuous Performance Test vs placebo, but showed no significant sleep or alertness improvements.
- Effect
- No Benefit
- Dose
- 3 mg
- Population
- Children/adolescents
RCTEffects of melatonin administration on daytime sleep after simulated night shift work2001n=21
An RCT of 21 subjects after simulated night shift found 1.8 mg sustained-release melatonin increased daytime sleep time on the first day only, without improving next-night alertness or performance.
- Effect
- Benefit
- Duration
- 2 days
- Dose
- 1.8 mg/day
- Participants
- 21
- Avg age
- 27±5
RCTCan melatonin improve adaptation to night shift?1998n=22
An RCT of 22 EMS personnel found 6 mg melatonin did not significantly improve night-shift adaptation, sleep, or alertness, though some secondary measures suggested modest benefit.
- Effect
- No Benefit
- Dose
- 6 mg
- Population
- Shift workers
- Participants
- 22
RCTDoes exogenous melatonin improve day sleep or night alertness in emergency physicians working night shifts?1998n=18
An RCT of 18 emergency physicians found 10 mg melatonin did not significantly affect daytime sleep or next-night alertness, though gestalt scores showed a non-significant trend toward benefit.
- Effect
- No Benefit
- Dose
- 10 mg/day
- Participants
- 18
RCTRandomized clinical trial of melatonin after night-shift work: efficacy and neuropsychologic effects1998
An RCT of 15 emergency physicians found 5 mg melatonin after night shifts did not improve recovery sleep quality, tiredness, or neuropsychological performance vs placebo.
- Effect
- No Benefit
- Dose
- 5 mg/day
Controlled trialImproving adaptation to simulated night shift: timed exposure to bright light versus daytime melatonin administration1995
A controlled study of simulated night shift found bright light produced stronger circadian phase shifts than melatonin (4 mg/day), though melatonin improved sleep quality without enhancing daytime performance.
- Effect
- Benefit
- Dose
- 4 mg/day
Evidence visualised
Same ratings as above, aggregated so you can see coverage and imbalance.
| Supplement | DEX | Studies | Meta-analyses | Share |
|---|---|---|---|---|
| Melatonin | ★★★★★56% | 13 | 2 | 100% |