Blue-Blocking Glasses

Blue-blocking glasses filter short-wavelength blue light (400-500 nm) from screens and artificial lighting, which is known to suppress melatonin production and shift circadian phase when exposure occurs in the hours before sleep. Evidence supports blue-light blocking as a sleep-support intervention: studies show improved sleep onset, increased melatonin levels, and better sleep quality in individuals wearing amber-tinted blue-blockers for 2-3 hours before bed. A 2021 meta-analysis confirmed statistically significant improvements in sleep quality across randomised trials. They benefit shift workers, late-night screen users, and anyone with difficulty winding down before sleep, particularly those unable to simply dim screens or avoid devices in the evening. Glasses that only filter a small fraction of blue light (clear-tinted 'computer glasses') have weaker evidence; amber-tinted lenses with >90% blue-light filtration perform best. PGSS take: A low-cost, no-pharmacology sleep tool with legitimate evidence, the lens colour matters. Clear lenses with minor filtration are not the same intervention as amber lenses worn in the 2-3 hours before bed.