Indoor Lighting's Missing Indigo Light May Help Prevent Myopia

Myopia, or nearsightedness, is rising sharply worldwide. Some experts estimate nearly 5 billion people — half the world's population — could be affected by 2050. Scientists have linked the trend to children spending more time indoors on screens and less time outside. New research from Cincinnati Children's and the University of Alabama at Birmingham (UAB) points to indoor lighting itself as a possible fix.

The study, published online Aug. 18, 2026, in the journal Cell Reports Medicine, examined indigo light, a short wavelength of visible light that is plentiful in sunlight but largely missing from standard white LED lighting. In tree shrews — small mammals whose eyes closely resemble human eyes — exposure to indigo light completely prevented the animals from developing myopia. "If indigo light can suppress myopia in these tests, then it should also be quite effective in humans," said corresponding author Richard Lang, PhD, of Cincinnati Children's.

Myopia develops when the eye grows too long, so light focuses in front of the retina instead of on it, blurring distant objects. Severe cases raise the risk of retinal detachment, glaucoma and macular degeneration. Earlier mouse studies found violet light near 380 nanometers could reduce myopia through a receptor called opsin 5 (OPN5), but eye lenses block most light below about 400 nanometers. The researchers found indigo light from 419 to 446 nanometers, which passes the lens while still activating OPN5, was most effective.

"We evolved outside in the full-spectrum light provided by our sun," Lang said. "When we live inside, we don't get all the wavelengths the eye needs for normal refractive development, and so we get myopia." Standard white LEDs peak near 450 nanometers and contain little indigo light. Cincinnati Children's Science of Light Center now plans to install indigo-enriched lighting in participating daycare spaces to track children's myopia rates over time.