The role of correlated colour temperature in myopia development and prevention.

Abstract

Identifying a balanced light environment that supports healthy ocular development is important. Correlated colour temperature (CCT, measured in Kelvin, K) of light sources, based on human visual perception, is believed to be associated with myopia, but its impact and underlying mechanisms remain unclear. This study aimed to review the literature and elucidate the potential relationship and biological mechanisms linking CCT and myopia. A systematic search was conducted across PubMed, Scopus, Web of Science and Embase, Wiley and Cochrane databases. Studies published from January 2000 to December 2024 that have explored the connection between CCT and myopia were included. PRISMA was used for data validity. A total of 10 articles were included in this review, comprising seven experimental studies and three population-based studies. The impact of CCT on myopia was inconsistent in different animal models. Human studies suggest high CCT artificial lighting environments may be associated with a higher progression of myopia. However, the effects of confounding factors may influence the results, and the number of relevant publications is limited. Although relatively lower CCT may have a protective effect against myopia, its influence is often confounded by spectral composition, making it difficult to isolate the specific role of CCT. Lower CCT light may have a protective effect against myopia, though this is not universal and further depends on wavelength, illuminance and exposure duration. Further research is needed to determine whether changes in CCT can help prevent and control myopia in humans, especially in combination with other myopia control treatments.