The Difference Between Infrared Sauna and Red Light Therapy

Whether it is visible or invisible to our eyes, light has bioactive effects on the human body. It affects us on a cellular, physical, and even emotional level. There has been extensive research (medical and purely cosmetic) over the last 20 years concerning the use of red and infrared radiation. You may have noticed some red-tinted photo on the internet, luring you to a session of red light therapy. Or perhaps someone you know mentioned infrared sauna. Is there any difference between the two? Definitely. In this article, we will shed some light on it.

Length matters

Every radiation has a different wavelength which is measured in nanometers (nm). The therapeutic effects on our organism are largely determined by the extent to which the light is able to penetrate our body tissues. For example, blue radiation has a relatively shorter wavelength (compared to red light), and is therefore used in therapy that targets the surface of the skin. Red and infrared light has longer wavelengths which allows it to penetrate into deeper layers of the skin. On the electromagnetic spectrum, these waves extend from radiation visible to the naked eye to the microwave spectrum which is invisible to the human eye. Even though we cannot see the waves from the microwave end of the spectrum, we perceive them as heat. We can divide them in three categories according to their wavelength:

1. Near-infrared 
2. Mid-wavelength infrared
3. Far infrared

Red light therapy

Red light therapy affects our body at the biochemical level through red and infrared radiation. Unlike the infrared sauna, red light therapy devices work their effects through light emitted by technological panels. For example, imagine a panel with special LED diodes. You can move this panel as you see fit, pointing it at different parts of your body, according to your needs. Size matters. Red light therapy devices are available in many different sizes nowadays. The larger the area of our body exposed to light, the more benefits we can get. It depends on the purpose for which we undergo therapy. Red and infrared radiation (650-850 nm) penetrates our tissues and stimulates our cells to produce more energy (1). This is achieved by acting upon the mitochondria in our cells that produce ATP energy (adenosintriphosphat). The more this energy is produced, the better our body can work as a whole and we feel full of energy and strength.

Red radiation with wavelengths around 660 nm can penetrate the outer layers of the skin and is easily absorbed by the surface tissues and cells. Depending on which body part we target, the light acts locally on individual skin layers, blood vessels, lymphatic pathways, or nerves. It promotes collagen production (2), blood circulation, and is also very popular for treating skin conditions and skin rejuvenation (3).

Near-infrared with its long waves (750-1100 nm) can penetrate even deeper, into deeper tissues, even through our bones. This therapy is suitable for muscle regeneration, brain health, or to alleviate joint ache (4). 

Infrared sauna

By infrared sauna we usually mean an enclosed cabin equipped with special radiators, usually emitting mid-wavelength and far-infrared radiation. Using far-infrared brings us the benefit of heat. Does this mean that an infrared sauna offers the beneficial effects of both light and heat? Are we killing two birds with one stone here? Unfortunately not. Due to high heat production, we cannot keep these radiators close enough to our body, and so the therapeutic effects of light are negligible. However, infrared radiation is able to penetrate deep into the muscle tissue, heating and relaxing it. Our body effectively absorbs most of the emitted light, and thus the surrounding air can stay at room temperature. This is very beneficial. It allows us to achieve profuse sweating and the associated benefits at much lower temperatures than we are used to from a traditional Finnish sauna. The heat improves our blood circulation, promotes detoxifying processes, lowers stress, and helps the body to relax.

Conclusion

Realising your purpose for exposing yourself to red radiation will help you make the final decision about what device to use. Are you planning to speed up recovery after training? Do you travel a lot and need something portable? Do you want to support mitochondrial function in order to have more energy? Then a red light therapy device might be the right fit.

Do you like the idea of a sauna but do not fare well in hot air and find it difficult to breathe? Do you feel that your body and mind need lower stress levels and want to treat yourself to some deep relaxation? Then perhaps an infrared sauna might be the best help.

Both techniques can provide both physical and mental benefits. It is important to realise, however, that in neither case will you feel the results overnight. What matters is long-term and regular use. Clarify your priorities, realise which area of your health you want to focus on and bring some more light into your life. 

Bibliography:

1. https://pubmed.ncbi.nlm.nih.gov/16144476/
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4126803/
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3926176/
4. https://pubmed.ncbi.nlm.nih.gov/27752476/