Far infrared heating utilizes far-infrared waves which are defined as electromagnetic waves having a wavelength of more than 4 µm. These far-infrared waves (rays with a peak wavelength of 8-14µm) are capable of deeply penetrating the human body, gently elevating the body’s surface temperature, and naturally stimulating other major bodily functions (1). In China, Japan, and Korea far infrared radiation has been widely applied in health promotion (2-4), food preservation (5 and 6), and in treatment of many vascular-related disorders (7 and 8).

A Brief History

In the 1400s, Koreans started using floor heating systems to improve the health of weak and elderly patients (9). This use of far-infrared irradiated warm surfaces has even been described as thermal therapy by numerous studies (10-12). Today Koreans spend most of their at-home  time barefooted. Because of this, most of their residential houses and apartments are now heated by an under floor heating system. Meanwhile most North American residential homes are heated by a primary forced air heating system.

floor surface temperature of 16–29°C not being sufficient for bodily thermal comfort

Forced air heating systems work by heating up air and circulating it throughout the premises. This causes the room temperature to be roughly equal to the floor temperature. This goes against researchers’ arguments of recommended indoor air temperatures of 18– 28°C and the floor surface temperature of 16–29°C not being sufficient for bodily thermal comfort in residential and office buildings (13).

can be maintained by our far infrared floor heating system at 27–33°C

In well-insulated buildings, however, the floor surface temperature can be maintained by our far infrared floor heating system at 27–33°C (which is recommended for increasing the blood flow rate and increasing thermal comfort) (14) while maintaining ambient air temperature at 20°C in an energy conscious building.

Research Summary

Attempts to experimentally analyze the effect of far-infrared rays on living organisms have produced some astonishing results. The most interesting have been in the areas of:

• Blood circulation
• Wound healing
• Autoimmunity and Inflammation Disorders
• Sleep Regulation
• Inhibiting effects to cancer cell lines and tumor

penetrate deep into the body warming it up from inside

Since the far infrared ray (with a peak wavelength of 8-14µm) may penetrate deep into the body warming it up from inside, all these effects may be based upon an indirect action of the irradiation to bring about a general improvement of the body state.

Blood Circulation

produces an appropriate supply of nutrients and oxygen to tissues

Far infrared treatments have proven to be very beneficial in many vascular-related disorders. A warm floor surface accelerates blood flow in the feet through vasodilatation and consequently produces an appropriate supply of nutrients and oxygen to tissues (15). By this process, mild thermal exposure increases microcirculation (16) and can regulate epidermis (outermost layer of skin) production (17). While a cold floor may induce a decrease in blood flow, reducing the supply of nutrients and oxygen by a restriction of blood supply to tissues (ischemia)(16).

The foot is the body’s extremity farthest away from the heart. Extremities like the fingers and toes control blood flow through vasodilation or vasoconstriction in order to maintain the temperature of important organs like the brain and heart near 37°C (17). Therefore the skin temperature and blood flow rate in extremities may indicate the level of thermal comfort and the health status of the whole body. We believe these are some of the fundamental reasons why far infrared radiation has proven itself successful in many aspects of health improvement.

increase in skin blood flow long after far infrared exposure

These improvements in blood circulation have been proven to not only occur while the far infrared rays are present, but to also last beyond initial exposure. One study demonstrated a significant increase in skin blood flow long after far infrared exposure (16). This has lead researchers to believe that far infrared therapy exerts a biological effect, and not just a body temperature rising effect, on the promotion and improvement of microcirculation.

Wound Healing

Researchers have shown that far infrared rays directly affect the biological processes of wound healing independently from the blood flow and the skin temperature. Specifically studies have indicated their direct affect on cellular proliferation and the secretion of regulatory proteins (cytokines).  Recent studies where even able demonstrate their ability to increase collagen generation and infiltration (10 and 11), which is believed by many to be a crucial element of any anti-aging skincare regimen.

Sleep Improvement

researchers believe that many of the health-improving properties of far-infrared are related to an improved sleep state

In laboratory conditions far infrared rays were shown to significantly prolong the duration of deep sleep (2). Deep sleep is believed by many to be the most crucial part of a good night’s sleep and is often referred to as REM sleep. This is the stage of sleep where the body muscles completely loosen and most of your nightly dreams occur (19). Without this crucial component of sleep, the body enters a physical and mental state of depression. This is likely why researchers believe that many of the health-improving properties of far-infrared are related to an improved sleep state.

Inhibition Of Cancer Cell Lines And Mammary Tumor Growth

FIR irradiation selectively inhibits the growth of specific cancer cell lines

Studies also suggest that far infrared radiation causes inhibiting effects to several human cancer lines. Specifically one study looked at the effect of FIR on the following cancer lines: A431 (vulva), HSC3 (tongue), Sa3 (gingiva), A549 (lung), and MCF7 (breast). This specific study concluded that “FIR irradiation selectively inhibits the growth of specific cancer cell lines” (20). Other studies have also demonstrated that the core body temperature increase induced by far infrared radiation can to substantially inhibit spontaneous mammary tumor growth in mice (21-25), which signifies a possibility in its potential on human tumor growth inhibition.

References

1. Inoue S, Kabaya M. Biological activities caused by far-infrared radiation. Int J Biometeorol 1989; 33: 145–150.

2. Honda K, Inoue S. Sleep-enhancing effects of far-infrared radiation in rats. Int J Biometeorol 1988; 32: 92–94.

3. Udagawa Y, Nagasawa H. Effects of far-infrared ray on reproduction, growth, behaviour and some physiological parameters in mice. In Vivo 2000; 14: 321–326.

4. Nagasawa H, Udagawa Y, Kiyokawa S. Evidence that irradiation of far-infrared rays inhibits mammary tumor growth in SHN mice. Anticancer Res 1999; 19: 1797–1800.

5. Lloyd BJ, Farkas BE, Keener KM. Characterization of radiant emitters used in food processing. JMicrow Power Electromagn Energy 2003; 38: 213–224.

6. Lee SC, Jeong SM, Kim SY, Nam KC, Ahn DU. Effect of farinfrared irradiation on the antioxidant activity of defatted sesame meal extracts. J Agric Food Chem 2005; 53: 1495–1498.

7. Kihara T, Biro S, Ikeda Y., et al. Effects of repeated sauna treatment on ventricular arrhythmias in patients with chronic heart failure. Circ J 2004; 68: 1146–1151.

8. Inoue S, Kabaya M. Biological activities caused by far-infrared radiation. Int J Biometeorol 1989; 33: 145–150.

9. Yeo, M.S., Kim, K.W., Seok, H.T. and Jang, K.H. (1995) A study on the historical changes and evolution of traditional ONDOL, J. AIK, 11, 93–103. [Korean]

10. Dano, K., Mori, N., Toda, K.I., Kobayashi, T. and Utani, A. (2001) Near-infrared irradiation stimulates cutaneous wound repair: laboratory experiments on possible mechanisms, Photodermatol. Photoimmunol. Photomed., 17, 261–265.

11. Toyokawa, H., Yoichi Matsui, Y., Uhara, J., Tsuchiya, H., Teshima, S., Nakanishi, H., Kwon, A., Azuma, Y., Nagaoka, T., Ogawa, T. and Kamiyama, Y. (2003) Promotive effects of far-infrared ray on full-thickness skin wound healing in rats, Exp. Biol. Med., 288, 724–729.

12. Masuda, A., Kihara, T., Fukudome, T., Shinsato, T., Minagoe, S. and Tei, C. (2005) The effect of repeated thermal therapy for two patients with chronic fatigue syndrome, J. Psychosom. Res., 58, 383–387.

13. Malchaire, J. and Durieux, N. (1995) Thermal comfort in nurseries, Indoor Air, 5, 129–135.

14. Song, G.-S. and Seo, J.T. (2006) Changes in the scrotal temperature of subjects in a sedentary posture over a heated floor, Int. J. Androl., 29, 446–457.

15. Kwak, H., Lee, S.Y. and Kim, S.B. (2003) Therapeutic heat and cryotherapy in family medicine, J. Korean Acad. Farm. Med., 24, 877–883. [Korean]

16. Yu, S.Y., Dhiu, J.H., Yang, S.D., Hsu, Y.C., Lui, W.Y. and Wu, C.W. (2006) Biological effect of far-infrared therapy on increasing skin microcirculation in rats, Photodermatol. Photoimmunol. Photomed., 22, 78–86.

17. Dano, K. and Sugie, N. (1996) Effects of near-infrared radiation on the epidermal proliferation and cutaneous immune function in mice, Photodermatol. Photoimmunol. Photomed., 12, 233–236.

18. ASHRAE (2001) ASHRAE Handbook Fundamentals, Atlanta, GA, American Society of Heating, Refrigerating and Air-Conditioing Engineers Inc.

19. Glossary. A resource from the Division of Sleep Medicine at Harvard Medical School, Produced in partnership with WGBH Educational Foundation". Harvard University. 2008. Retrieved 2009-03-11.

20. Ishibashi J, Yamashita K, Ishikawa T, Hosokawa H, Sumida K, Nagayama M, Kitamura S. (2008) The effects inhibiting the proliferation of cancer cells by far-infrared radiation (FIR) are controlled by the basal expression level of heat shock protein (HSP) 70A,Med Oncol., 25(2), 229–237.

21. Udagawa Y, Nagasawa H, Kiyokawa S. Inhibition by whole-body hyperthermia with far-infrared rays of the growth of spontaneous mammary tumours in mice. Anticancer Res 1999;19(5B): 4125–30.

22. Udagawa Y, Nagasawa H. Effects of combined treatment with coffee cherry and whole-body hyperthermia on the growth of spontaneous mammary tumours in SHN mice. In vivo 2000;14(3):431–5.

23. Udagawa Y, Inada K, Nagasawa H. Inhibition by single wholebody hyperthermia with glucose administration of the growth of spontaneous mammary tumors in mice. Jpn J Hyperthermic Oncol 2000;16:229–36.

24. Nagasawa H, et al. Different schedules of whole-body hyperthermia with or without glucose for the inhibition of mammary tumors and uterine adenomyosis in SHN mice. Bull Sch Agr, Meiji Univ 2001;127:43–51.

*DISCLAIMAR* Geo Dream Heat Inc. or any of its partner companies do not make any direct claims, promises or guarantees in regards to the benefits outlined above. The research has been gathered, from what we believe to be reliable academic resources, only as a point of reference in order to provide readers with a general overview of what far-infrared irradiation can potentially offer its user.