Evening Blue‑Light Blocking Glasses: Randomized Crossover Trial
Summary
This randomized crossover trial tested whether wearing blue light–blocking glasses in the evening could improve sleep in 20 healthy adults. Participants alternated between one week of wearing blue-blocking lenses and one week of clear control lenses from 6 p.m. until bedtime. Results showed that the blue-blocking glasses modestly improved some subjective sleep measures, such as falling asleep slightly faster and waking up fewer times during the night. However, objective sleep data from actigraphy did not show meaningful improvements, and total sleep time was even slightly shorter in the blue-blocking condition. Overall, the study suggests only limited benefits for healthy adults.
Why It Matters For Night Shift Workers and Night Owls
For people trying to rest on irregular schedules, blue-blocking glasses may help reduce stimulating light signals and make it easier to wind down, even if they don’t increase total sleep time. This means they can still be a useful tool for night-shift workers looking to improve daytime sleep after a shift or for easing the transition back to a regular schedule on days off. But the evidence also shows that glasses alone won’t “fix” sleep—they work best as one part of a broader routine that also includes consistent sleep timing, a dark environment, and limited late-night screen use.
Notes
Population: healthy adults (not shift workers).