The Ultra Low EMF Nano-Carbon panel heaters in Sun Stream Infrared Saunas emit Far Infrared (FIR) with approximately 70% of the heaters output lying between 5-15 microns (5000nm – 15000nm) and approximately 90% of the output lying between 1-20 microns (1000nm-20,000nm). Thus, our heaters also encompass the Mid Infrared range of 1.4- 3.0 microns.
Sun Stream also has a full line of Evolve Light Therapy LED based products emitting either Red (660nm) or Near Infrared (850nm) which can be used inside or outside of our saunas.
In the market place we currently have three different types of Infrared saunas:
- Far Infrared (FIR)
- So called Near Infrared (NIR) Saunas
- Full Spectrum Saunas (RED, NIR, MIR, FIR)
Far Infrared (FIR) Saunas
FIR is absorbed by the water content in our skin (1- 4mm depth) and generates heat which is then drawn into deeper levels of our muscles and joints. Absorption is the key dynamic to generate heat in your body which, of course, is the primary purpose of a sauna.
All light when it hits an object, such as our body, is either absorbed, reflected or transmitted (passes through). FIR is highly absorbed, has a low reflection rate and a low transmission rate making it the best wavelength for the purposes of heating the human body. All carbon and ceramic based sauna heaters produce most of their energy in the FIR range.
Near Infrared (NIR) Saunas
NIR has a low absorption rate and therefore generates very little heat in our bodies. NIR has a high transmission rate and passes through our tissue where several biochemical reactions occur associated with cellular energy production and healing. There is decades of research and 1000s of studies published on the therapeutic benefits of NIR and Red light which is known as Photobiomodualtion Therapy (PBMT) or Low Level Light Therapy (LLLT) in the medical literature. All of the PBMT research has used either lasers or LED sources of Red and NIR light emitting single frequencies of these wavelengths. 660nm for visible Red light and 850nm for invisible Near Infrared are the specific frequencies often used in the research. The research has discovered that our cells’ chromophores (light receptors) respond to a high intensity of a single frequency in the mid 600s nm and mid 800nm ranges.
Some sauna companies are promoting Near Infrared for the purpose of a sauna who seem to have a poor understanding of the science of NIR. Again, NIR generates very little heat in our body. Some sauna companies are using incandescent heat lamp bulbs or quartz halogen tube heaters which produce only a small amount of NIR and have very very hot filaments. Neither of these incandenscent devices emit their NIR at single frequency as has been done with the LEDs or lasers in all of the PBMT/LLLT medical research.
Light disperses over distance and it is essentially impossible to be close enough to these lamps or tubes, due to their extremely hot surface temperatures, to receive an adequate level of NIR energy.
Lasers and LEDs on the other hand are capable of producing the single frequency wavelengths for therapy and can be comfortably positioned close enough to the body, even pressed right into our skin, to ensure the delivery of therapeutic levels of light energy.
Using Near Infrared in a Far Infrared sauna may help one save some time by combining these 2 different therapies together however it is not the ideal situation for administering light therapy. Near Infrared will transmit through our tissue best when we are at normal temperature rather than when we are heated up in the sauna and when our skin is not covered in a layer sweat.
Therefore a “Near Infrared Sauna” is a contradiction of terms. The primary function of a sauna is to generate heat in your body to raise your core temperature, boost your immune system and induce a heavy sweat. Near Infrared generates very little heat in your body as it passes through our tissue and does not serve the hyperthermic purpose of sauna.
Full Spectrum (RED, NIR, MIR, FIR)
Some companies, are advertising ‘full spectrum’ saunas that incorporate invisible Near Infrared light and Mid Infrared light into their Far Infrared saunas.
Mid Infrared (MIR) is not well studied. Outside of the advertising from certain ‘full spectrum’ sauna companies we have been unable to find any information indicating particular benefits of MIR which makes up a very small portion of the light spectrum (only 1.4- 3.0 microns). Mid Infrared is likely absorbed by the water content in our skin as is Far Infrared and can add to the heating effect of the sauna.
The benefits of NIR and Red light are entirely dependent upon the proximity of the user to the light source to receive an adequate intensity of light energy.
Unfortunately, the full spectrum saunas on the market DO NOT provide adequate levels of NIR in close enough proximity to the user’s body to deliver therapeutic levels of the light.
As mentioned, some sauna companies are recommending the use of common Near Infrared heat lamps (Home Depot etc) for NIR therapy purposes. These heat lamps are extremely hot and it is impossible to place your skin close enough to the bulbs to receive therapeutic levels of NIR.
The same is true of the quartz halogen tube heaters used in some full spectrum saunas. Both of these devices emit over a wide range of frequencies covering visible light, Near, Mid, and Far Infrared. They do not emit a high level of Red or NIR energy at a single frequency as the medical research has determined to be necessary to stimulate our cells’ light receptors
LEDS, on the other hand, DO NOT emit dangerous levels of heat and can be close to or even directly on your skin to ensure that therapeutic levels of the NIR light are transmitted into our tissue.
Some full spectrum sauna designs do mount small panels of LEDs on the wall of the sauna. These designs have very limited effect as it is unlikely that the user will be able to position the desired body part close enough to the wall mounted LEDs to receive adequate light energy.
