Research

Hormonal

Phase-shifting the circadian clock via controlled light/dark exposure and melatonin reduces circadian misalignment, thereby improving night-shift alertness and performance more effectively than symptomatic countermeasures like caffeine or naps.

To work night shifts safely and healthily, you must reset your body clock, not just mask sleepiness. Use bright light (4000+ lux) for short bursts during your shift, wear dark sunglasses on your commute home to block morning light, and sleep in a pitch-black room. Consider taking melatonin (0.5-3mg) in the morning to help delay your clock. This aligns your biology with your schedule, reducing long-term health risks and improving alertness.

GoodSupportsHIGH confidence
The most reliable way to reduce the sleepiness, fatigue, impaired performance, safety problems, and, presumably, health risks of shift work is to reduce circadian misalignment. ... We contend that these [caffeine, naps, melatonin for sleep], while better than nothing, are not enough because they do not address the underlying cause of the problems, which is circadian misalignment.
Charmane I. Eastman et al. · Nature and Science of Sleep · 2012

Why this rating

Based on multiple simulated night-shift studies and field studies with objective phase markers (DLMO, Tmin).

Source

Shift work: health, performance and safety problems, traditional countermeasures, and innovative management strategies to reduce circadian misalignment

Charmane I. Eastman et al. · Nature and Science of Sleep · 2012

DOI 10.2147/nss.s10372

narrative_reviewCited 168×
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DOI resolved against Crossref · corpus check 2026-06-10

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