Randomized controlled trial of blue‑enriched light to improve alertness and performance in night shift workers
Summary
This randomized controlled trial compared blue-enriched lighting with standard white light during simulated night shifts in 71 night-shift workers. Across the night, both groups became sleepier, and no overall performance benefits were found with blue-enriched light. However, when exposure overlapped with the timing of melatonin rhythm peaks, participants under blue-enriched light reported less subjective sleepiness than those under standard lighting.
Why It Matters For Night Shift Workers and Night Owls
For night workers, this study shows that blue-enriched light is not a universal fix for fatigue. While it may help reduce feelings of sleepiness when timed to match the body’s circadian rhythm, it did not improve overall performance across the shift. This means that lighting can play a role in fatigue management, but it needs careful timing and should be combined with other strategies—like naps, breaks, or consistent scheduling—to reliably support alertness and safety.
Notes
Occupational and Environmental Medicine (2017).