In 2018, there was a meta-analysis of 9 clinical trials found that 5 weekly sessions of infrared sauna for 2 - 4 weeks, was associated with a significant reduction in brain natriuretic peptide (BNP). This is a marker of heart failure progression. It also is associated with cardiothoracic ration. This is an indicator of heart enlargement. It also improved left ventricular ejection fraction but no significant effect on left ventricular end-diastolic diameter, systolic blood pressure or diastolic blood pressure.
There are claims of detoxification. This is due to naturopaths believing that toxins leave the body through sweat. This is the reason these quacks believe that infrared saunas are a good treatment to try to reverse autism. This is not the case. There is no scientific evidence showing that it has any detoxification properties.
According to the International Commission on Non-Ionizing Radiation Protection (ICNRP), the risks of Infrared therapy are:
- thermal injury, an injury can be present even if pain is not felt
- telangiectasias (widened tiny blood vessels are visible on the skin)
- Reduced DNA repair efficiency
- Can promote skin cancer initiated by other triggers
- Thickening of the skin
- Retina damage
- Eye lens damage, leading to cataracts
- Hyperthermia (core body temperature is too high)
International Commission on Non-Ionizing Radiation Protection. ICNIRP statement on far infrared radiation exposure. Health Phys Journal 91(6):630-645; 2006.
Naik S (21 September 2008). "Infrared Radiation". Scribd.com. Retrieved 12 December 2013.
Rice C (12 July 2017). "Don't Call it Sauna". Sauna Digest. Medium.
Källström M, Soveri I, Oldgren J, Laukkanen J, Ichiki T, Tei C, et al. (November 2018). "Effects of sauna bath on heart failure: A systematic review and meta-analysis". Clinical Cardiology. 41 (11): 1491–1501. doi:10.1002/clc.23077. PMC 6489706. PMID 30239008.