There have been quite a number of recent studies into the use of light for medical/health purposes -- for example, using blue light for its antimicrobial effect

There have been quite a number of recent studies into the use of light for medical/health purposes -- for example, using blue light for its antimicrobial effects[0], or various wavelengths of light for other healing effects[1,2]. Use of LED light for this purpose is often covered by insurance and has been developed & used by NASA[3]. Anecdotally, a family member of mine has one of those "led light therapy" systems[4]. Initially he was going to a local clinic to use one and ended up buying one of the packages for himself. I have seen person after person experience shockingly beneficial effects from using them (like people are saying "this is the first time I've slept without pain medication in years". From putting a pad covered in bright LEDs on them for 40 minutes. People are so skeptical, then suddenly their chronic pain issue is mitigated by simply sitting there. 0: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3438385/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3438385/ 1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4126803/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4126803/ 2: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3799034/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3799034/ 3: https://www.nasa.gov/topics/nasalife/features/heals.html https://www.nasa.gov/topics/nasalife/features/heals.html 4: https://www.balancedlivingllc.com/light-therapy.html https://www.balancedlivingllc.com/light-therapy.html