Far Infrared rays (FIR) are invisible and present in sunlight and were first discovered by a scientist named Sir William Herschel in 1800. His research led to the discovery that there were not only the known visible rays – red, orange, yellow, green, blue and violet – but there were also invisible rays later named Infrared.
Approximately 80% of solar energy is made up of FIR and 60% is between the ranges of 4-20 microns where it is the safest and the most beneficial to the human body. The human body also generates FIR on its own within the tissues.
All parts of the human physiology are dependent on FIR. It is a nourishing energy. Without it, we die.