This is an excellent article about Red Light Therapy (RLT) for lay people. Briefly, the take-home messages are:
It works.
But only if you buy a light with two specific wavelength ranges: 630-670 nm and 850 nm
The mid-600's stimulate (heal) skin issues such as wrinkles, scars, wounds, and baldness
The mid-800's penetrate deeper and target bones, muscles, and even the pineal gland and hypothalamus
YOU CAN STIMULATE YOUR BRAIN!
Choose your lights carefully. The author of the article, Alex Fergus, mentions Joovy only once but they have high production standards and do their own extensive research
Men can raise their testosterone levels by shining the light on the boys.
I'll add my own piece of advice. The closer to your skin the deeper the light penetration. But first and second degree burns are very real risks. I should know.