This question from a reader prompted me to investigate use of infrared as a treatment for inflammation, pain and autoimmune diseases.
Here’s what I found…
Mayo Clinic describes infrared saunas as being similar in function to heat saunas: regular heat saunas warm the body by producing heat in the air around the body; infrared saunas produce warmth directly, generating heat in the tissues (similar to the way longer wavelength microwaves heat food). They report these treatments are considered safe, with no reports of adverse effects.
While we are all familiar with light emitting diodes (or LEDs) in our TVs and lightbulbs, infrared-LEDs (or IR-LEDs) emit light in a specific wavelength that is longer than visible red light – somewhere in the range of 800-1000 nanometers (nm). Infrared rays are invisible to humans but sometimes appear red due to a small amount of red or orange wavelength light being also emitted.
Infrared light waves can penetrate the skin up to 3 – 4 cm, depending on the wavelength and power intensity of the LED. While the IR-LED does not feel warm on the skin (or only slightly warm), it generates heat in and below the surface of the skin. Users will usually describe sweating during use.
In addition to generating heat, studies have found that IR-LEDs reduce “mediators of inflammation”, substances that the body produces to create and sustain the inflammatory process. Infrared LEDs also dilate blood vessels. They are used in medicine to reduce edema (swelling caused by increased fluid in the tissues), reduce production and movement of inflammatory substances, and to accelerate skin and connective tissue healing.
Studies have demonstrated increased healing rates of 25-35% post-surgery and similar rates of improvement in soft tissue injury, such as sprains. IR-LEDs have also been shown to decrease pain and increase range of movement in injuries with no bone involvement, such as tennis elbow.
Many diseases of aging, for example rheumatoid arthritis, involve production of inflammatory substances that have been shown to be reduced by IR-LED irradiation, suggesting a potential use in these diseases. Animal studies suggest IR-LED may also improve healing of nerve lesions but, as of the publication of the articles I found, additional study was still needed.
Infrared-LEDs are available as small portable units as well as complete saunas. The technology is considered very safe to use, with the exception of early pregnancy when no saunas of any type are recommended (increased body temperature can be harmful to the baby). I would expect heat therapy would be safe for small area treatment, such as a joint, with a hand-held unit but best, as always, to check with your doctor first.
Regarding IR-LED use in autoimmune diseases, the focus of the question I received, there didn’t seem to be as much research available. Infrared-LED seems to be primarily recommended for inflammatory diseases: cardiovascular disease, diabetes, rheumatoid arthritis, Chronic Fatigue Syndrome, chronic muscle and joint pain, poor digestion and anger/depression (although no mechanism was given for these last two actions). Infrared saunas are recommended for those with increased blood pressure who wish to use a sauna. They cause a temporary reduction in pressure due to dilation of blood vessels, as compared to heat saunas that raise blood pressure when used.
Only one reference I found (blog by physician Amy Myers) referred to autoimmune action. She described many of the benefits of infrared LED as being produced by vasodilation and increased blood circulation to the area. She also described differences in various wavelengths of infrared radiation:
Near-infrared (shorter wavelength) – best for wound healing and improving immune function
Middle-infrared – ideal for increasing circulation and promoting muscle relaxation
Far-infrared (longer wavelength) – mainly for detoxification
I would expect that one would need to use a sauna-style of near infrared LED to expose the entire body to achieve immune effects. A hand-held unit could be used when only a small area needs to be treated for pain or inflammation.
It is recommended to use IR-LED for 5 to 30 minutes, with one source recommending no longer than 20 minutes per session. Sessions can be repeated several times daily, however. The effect is considered useful for temporary relief when used for pain and inflammation.
Bottom line…
For pain and inflammation, infrared-LED can be useful but would be expected to give subtle improvements. There does not yet appear to be a lot of scientific study for its use in autoimmune disease but it is safe and not extremely expensive for those who want to try it. For relaxation or detoxification (produced by sweating), infrared saunas would function similarly to heat saunas.
Healthy Aging Review 2015
