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Recently, violet light, exhibiting a unique wavelength of 360\u2013400\u2009nm, has garnered significant attention due to its perception through a specific receptor, marking a novel research area. Herein, we used \u201cviolet light glasses\u201d that directly emit violet light into the human eye and investigated their effects on healthy humans in real-life settings. This study demonstrated that two hours of violet light exposure in the morning enhanced sleep quality in approximately 20% of the healthy participants and was also associated with improved blood glucose levels. Although this was a pilot study due to its small sample size, our findings indicate that violet light could potentially promote health benefits in humans.<\/jats:p>","DOI":"10.1371\/journal.pone.0314346","type":"journal-article","created":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T17:26:29Z","timestamp":1755797189000},"page":"e0314346","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Violet light could improve sleep quality and blood glucose levels in healthy individuals: A pilot 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