Declining eyesight can be improved by looking at red light, pilot study says - CNN
▻https://www.cnn.com/2020/06/30/health/declining-eyesight-red-light-scn-wellness/index.html
The study was small, a pilot study to test the concept. Researchers recruited 12 men and 12 women, whose ages ranged from 28 to 72. Each participant was given a small handheld flashlight that emitted a red light with a wavelength of 670 nanometers. That wavelength is toward the long end of the visible spectrum, and just short of an infrared wavelength, which tends to be invisible to the human eye.
They spent three minutes each day looking into the light over a period of two weeks.