Generally speaking, red/NIR light has two central mechanisms in how it benefits cellular function and overall health: 1.Stimulating ATP production in the mitochondria through interacting with a photoreceptor called cytochrome coxidase.
2. Creating a temporary, low-dose metabolic stress (known as hormesis, which is also a primary mechanism of why exercise works) that ultimately builds up the anti-inflammatory, anti- oxidant and cell defense systems of the cell.
Obviously, red light is best suited for treating skin conditions, local pain, mild inflammation, and accelerating surface wounds healing. And what is trustworthy is that there are no adverse side effects. Red light does not create heat, although you might experience a mild and pleasant warm sensation on your skin during therapy, but it won't burn your skin or damage any underlying body tissues.
It has been proven that almost all wavelengths of red light will provide a sort of benefits, but wavelength from 650nm to 850nm demonstrate the most healing power.