Far infrared therapy has been studied for decades as a form of passive heat therapy.
Unlike red light and near infrared therapy, which are primarily studied for photobiomodulation, far infrared therapy is most commonly studied for its effects on circulation, cardiovascular health, recovery, and overall well-being.
Much of the modern infrared sauna industry is built upon this growing body of research.
What Is Far Infrared Therapy?
Far infrared light occupies a much longer wavelength range than red light or near infrared light.
Far infrared wavelengths are measured in microns rather than nanometers.
Many infrared sauna heaters operate within the 8 to 10 micron range, which closely corresponds to the wavelengths associated with human body heat.
Rather than simply heating the surrounding air, far infrared energy is absorbed by tissues and contributes to a warming effect within the body.
Circulation Research
One of the most frequently studied effects of far infrared therapy is circulation.
Researchers have examined how passive heat exposure may influence blood flow and vascular function.
Improved circulation is often proposed as one mechanism contributing to many of the benefits observed in sauna research.
Cardiovascular Health
Far infrared therapy has attracted significant attention in cardiovascular research.
Researchers have investigated the relationship between passive heat therapy and:
- Vascular function
- Blood pressure
- Endothelial function
- Circulatory health
- Quality of life
Much of this research has contributed to the development of Waon Therapy, a structured form of far infrared heat therapy developed in Japan.
Recovery and Relaxation
Far infrared therapy has also been studied for:
- Recovery
- Relaxation
- Flexibility
- Comfort
- Quality of life
Researchers continue to explore the biological mechanisms responsible for these outcomes.
Several proposed mechanisms include:
- Improved circulation
- Nitric oxide pathways
- Heat shock proteins
- Cellular signaling
- Mitochondrial function
Quality of Life Research
One of the most interesting aspects of far infrared research is its focus on quality-of-life outcomes.
Many studies evaluate how participants feel, function, and perform daily activities rather than focusing solely on laboratory measurements.
This broader perspective helps researchers understand how heat therapy may affect overall wellness.
What Does the Research Suggest?
The strongest body of far infrared research currently focuses on:
- Circulation
- Cardiovascular health
- Recovery
- Relaxation
- Flexibility
- Quality of life
Research continues to expand as scientists work to better understand the biological responses associated with passive heat therapy.
Related Reading
Photobiomodulation: Understanding How Light Influences Cellular Function
https://celebrationsaunas.com/photobiomodulation/
ATP and Mitochondria: Understanding the Body’s Cellular Energy System
https://celebrationsaunas.com/atp-and-mitochondria/
Red Light, Near Infrared, and Far Infrared Therapy: What Each Wavelength Does in the Body
https://celebrationsaunas.com/red-light-near-infrared-and-far-infrared-therapy/
What Is Waon Therapy? Understanding the Science Behind Far Infrared Sauna Research
https://celebrationsaunas.com/what-is-waon-therapy/
Sources & Further Reading
The Multifaceted Benefits of Passive Heat Therapies
https://pmc.ncbi.nlm.nih.gov/articles/PMC10989710/
Mayo Clinic – Infrared Sauna FAQ
https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/infrared-sauna/faq-20057954