Far infrared radiation (FIR): its biological effects and medical applications

Abstract

Far infrared (FIR) radiation (λ = 3-100 μm) is a subdivision of the electromagnetic spectrum that has been investigated for biological effects. The goal of this review is to cover the use of a further sub-division (3- 12 μm) of this waveband, that has been observed in both in vitro and in vivo studies, to stimulate cells and tissue, and is considered a promising treatment modality for certain medical conditions. Technological advances have provided new techniques for delivering FIR radiation to the human body. Specialty lamps and saunas, delivering pure FIR radiation (eliminating completely the near and mid infrared bands), have became safe, effective, and widely used sources to generate therapeutic effects. Fibers impregnated with FIR emitting ceramic nanoparticles and woven into fabrics, are being used as garments and wraps to generate FIR radiation, and attain health benefits from its effects.

Keywords: FIR emitting ceramics and fibers; biogenetic rays; blackbody radiation; far infrared radiation; infrared sauna; radiant heat.

Figures

Figure 1

The spectrum of electromagnetic radiation and some biological changes it may induce.

Figure 2

(A) Planck’s law. Dependence of spectral radiant emittance (ωλ) for perfect blackbodies as a function of wavelength (λ). (B) Wien’s displacement law. The wavelength of maximal radiant exitance (λmax) as a function of the absolute temperature (T) for a perfect black body (dashed line) and different bodies.

Figure 3

Medical FIR sources. (A) WS TY-301R® and (B, C) WS TY-101N® FIR lamps (both by WS Far Infrared Medical Technology Co., Ltd., Taipei, Taiwan).

Figure 4

FIR sauna. (A, B) Comparison of FIR sauna with conventional heated sauna. (C) Cabin incorporating FIR emitting “cold” unit(s) (Anhui Hi-Tech Electronic Commerce Co., Ltd., Hefei, China).

Figure 5

FIR emitting garments and fabrics manufactured from fibers impregnated with ceramic nanoparticles (Celliant®, Hologenix, Santa Monica, CA, USA). (A) fibers, (B) yarns, (C) fabrics, (D) knee bandage brace, (E) socks, (F) gloves, (G) elbow bandage brace, (H) multi-purpose bandage, (I) performance apparel, (J) mattress, and (K) puppy blanket.