Light‑Emitting Blue‑Enriched Glasses During Early‑Morning Night‑Shift Hours: Field Study
Summary
This field study tested whether blue-enriched light–emitting glasses could reduce fatigue and improve performance during the toughest part of a night shift—the early morning hours. Twenty-one shift workers used either blue-light glasses or dim red light glasses from 5:00–5:30 a.m. While sleepiness naturally increased across the night, the blue-light glasses did not significantly improve alertness or attention compared with the red-light control. However, participants rated the blue-light glasses as comfortable and reported no side effects, showing that wearable light devices can be used safely and conveniently in real work settings.
Why It Matters For Night Shift Workers and Night Owls
The hardest part of a night shift often comes just before dawn, when the body is naturally at its sleepiest. This study shows that while blue-light glasses may not dramatically boost alertness, they are safe, easy to use, and could be one piece of a broader fatigue-management strategy. For workers, the practical lesson is that portable light exposure is possible—but it may need to be combined with other strategies, like naps or caffeine timing, to make a real difference in staying alert on the job.
Notes
Real‑world implementation.