Light starvation: the role of at-home red and near-infrared photobiomodulation therapy in counteracting modern sunlight deficiency risks

Human physiology evolved under continuous exposure to the full spectral composition of natural sunlight. Modern lifestyles, however, are characterized by prolonged indoor living and extensive reliance on artificial lighting, resulting in markedly reduced exposure to biologically significant wavelengths, particularly in the red and near-infrared (NIR) regions. This condition, often described as light starvation, has been increasingly associated with altered cellular bioenergetics, circadian dysregulation, cognitive and mood-related effects, and reduced overall well-being. This paper examines the biological relevance of red and NIR light, reviews the mechanistic foundations of photobiomodulation (PBM), and discusses the potential role of at-home PBM therapy as a practical strategy to mitigate risks associated with modern sunlight deficiency.