Amazing stuff! Good news! A very clever experiment.
"Efforts to explain rising rates of myopia, or nearsightedness, in children worldwide have made two things clear: More time spent outdoors seems protective, and more time spent indoors increases risk.
A new study in tree shrews now suggests a key to preventing myopia may be the indigo portion of sunlight. ...
In the new study, researchers first induced myopia in tree shrews—diurnal mammals that can serve as a model for primate visual systems—by fitting them with tiny spectacles that focus light at a point behind the retina, tricking it into growing longer to compensate.
The team found that indigo light (wavelengths between 419 and 446 nanometers) activated a light-sensing protein on the tree shrews’ retinas called OPN5, linked in mouse models to myopia prevention.
These indigo wavelengths are more abundant in natural sunlight than modern indoor lighting, and increasing their presence in the lights illuminating the animals’ indoor enclosure prevented myopia induced by the spectacles.
The results have not yet been confirmed in humans, but some of the authors are involved in companies developing classroom lighting and LED-equipped glasses that aim to give children’s eyes a steadier diet of indigo."
From the highlights and abstract:
"Highlights
• Indigo light suppresses lens-induced myopia in tree shrews
• The most protective wavelength range is 419–446 nm
• Tree shrew lens filtering shifts effective OPN5 stimulation to indigo
• Built environments may lack protective indigo wavelengths
Summary
Today, about 2.8 billion people worldwide suffer from myopia (nearsightedness), and projections place the 2050 burden at 4.8 billion people (the “myopia boom”). Myopia results from abnormal elongation of the eye, which causes images to focus in front of the retina.
Building on prior work in mouse models assessing the non-visual opsin OPN5, we test the hypothesis that insufficient exposure to short-wavelength light increases myopia susceptibility.
We use the tree shrew, a near-primate model for human myopia. Our findings show that indigo light in the range of 419–446 nm, when used to supplement a warm white light-emitting diode (LED), completely suppresses myopia induced by minus-lens wear.
A large body of genetic and epidemiological evidence suggests that the “myopia boom” has an environmental cause.
Our findings align with this evidence and suggest that one contributing factor is the relative absence of indigo light in built environments where we spend 86% of our time."
Myopia and Indigo Light: Grytz Pushes Boundaries in Vision Research (a related, but older original news release from August 2025)
Graphical abstract
Figure 1 Expression of OPN5 in ganglion cells of the tree shrew retina
