The study conducted by Shi-Yau Yu, Jen-Hwey Chiu, and colleagues explored the effects of far-infrared (FIR) therapy on skin microcirculation in rats. The researchers hypothesized that FIR could increase skin blood flow through mechanisms other than its thermal effects. To test this, the team applied FIR treatment to rats and measured skin blood flow using a laser Doppler flowmeter. The results showed that while FIR treatment did not cause a significant change in skin blood flow during the application, blood flow increased significantly after the FIR emitter was removed, particularly when the rats were treated for 45 minutes. This effect was sustained for up to 60 minutes and was found to be independent of thermal effects, indicating that FIR therapy has a non-thermic biological impact on skin circulation. Further analysis revealed that the increase in blood flow was mediated by nitric oxide (NO), as it was suppressed when an endothelial nitric oxide synthase inhibitor was used.
This research highlights the potential of FIR therapy, such as that used in infrared saunas, to improve skin microcirculation, especially in conditions involving ischemia (reduced blood flow) like trauma, diabetes, and peripheral artery disease. By stimulating the L-arginine/NO pathway, FIR therapy could enhance blood flow to affected tissues, promoting healing and recovery. In particular, this study supports the idea that infrared saunas, which emit FIR light, could be beneficial in treating chronic wounds, improving tissue oxygenation, and accelerating recovery in conditions where blood flow is compromised. By increasing nitric oxide production and enhancing circulation, FIR therapy offers a non-invasive option for improving wound healing and tissue regeneration.
