Study Finds Indigo Light Suppresses Myopia in Tree Shrews; Startup Develops Light-Emitting Eyewear

A study published in Cell Reports Medicine suggests that reduced indigo light in built environments may contribute to rising global myopia levels. Experiments on tree shrews indicated that indigo light combined with warm LED lighting suppressed myopia, with the most protective wavelength identified as 419–446 nanometres. Researchers noted this wavelength is scarce indoors but abundant in sunlight, potentially explaining why outdoor time reduces myopia risk. The authors proposed that blue-blocking spectacles might increase myopia risk by filtering these wavelengths. Lead author Professor Rafael Grytz from the University of Alabama at Birmingham established a startup, Electric Indigo, which received a $357,000 grant from the National Eye Institute in 2025 to develop light-emitting eyewear for myopia prevention.