Perfect, because so do we!

LEDs provide the ability to produce a single wavelength of light instead of the many wavelengths of light that the standard lightbulb produces. LEDs initially only emitted red light, but were later developed to emit light at many different wavelengths, each with varying levels of penetration. Several sources note that LED therapy was used as a method of treating pain and arthritis in Eastern Europe soon after being invented, however, medical research into this area did not begin until later.

We've collated some referenced articles and linked them in the below posts if you'd like some more reading.