What Temperature Should a Sauna Be? (Backed by Science)

Connie Zach emphasizes that while some prefer to exercise in the sauna, a parasympathetic state is more effective for detoxification. She highlights that infrared saunas uniquely facilitate this shift from fight-or-flight to rest-and-digest, which is crucial for the body's healing processes. This state allows for better release of toxins, reduction of stress hormones like cortisol, and an increase in 'happy chemicals' like dopamine and serotonin. She mentions a study demonstrating infrared's positive impact on autonomic nervous system function and cardiac function, measured by heart rate variability, making it particularly beneficial for high-stress individuals.

Ben Greenfield notes that studies support the benefit of increasing core temperature post-exercise, leading to a significant rise in erythropoietin (EPO). EPO is known to increase red blood cell production, which improves oxygen transport and overall cardiovascular fitness, even in the absence of further physical exertion. Connie Zach agrees, stating she delays showering after her sauna sessions to extend this beneficial heat effect. While acknowledging the discomfort, particularly in dry saunas, Ben suggests that even moving around a little in the sauna post-workout can be a valuable tool for cardiovascular athletes.

Ben Greenfield emphasizes that being well-hydrated and mineralized is crucial for maximizing the benefits of infrared sauna, particularly the water structuring effects that Connie Zach discussed. This optimal state allows the body to better absorb and utilize the light energy, leading to improved flow, oxygen and blood circulation, and ATP production. While not strictly necessary, it enhances the overall therapeutic cascade initiated by infrared exposure.

Connie Zach strongly recommends using protective coverings, ideally made of an infrared-compatible, super-absorbent material, on sauna benches. This is to prevent direct contact with sweat that contains detoxified substances, such as heavy metals, and to maintain hygiene. She also suggests having a small face towel for wiping away sweat, particularly from the face and gut area, where sweating is often profuse. This practice ensures that the expelled toxins are not reabsorbed and that the sauna environment remains clean.

Connie Zach and Ben Greenfield strongly advise against bringing phones or other electronic devices into the sauna. While Sunlighten has extensively engineered their saunas for extremely low or non-existent EMF, the concern is that the combination of heat and EMF from personal devices could be problematic. Beyond potential physical effects, the primary reason is to eliminate distractions and allow the user to fully engage in a parasympathetic state. This state is essential for deep relaxation, mental recharging, and optimizing the body's detoxification and healing mechanisms. Ben describes his personal practice of using this time for reflection and setting intentions, emphasizing the importance of an uninterrupted, focused experience.

Connie Zach, co-founder of Sunlighten, asserts that significant research on infrared therapy has existed for nearly 30 years, particularly concerning cardiovascular health. She explains that the lack of commercial interest from pharmaceutical companies or other large entities meant this research wasn't widely promoted or elevated to public awareness. Sunlighten itself has conducted studies, including one measuring core temperature increase and another with UMKC demonstrating statistically significant reductions in blood pressure using their products, directly countering the notion of insufficient scientific backing.

Connie Zach highlights that infrared is a spectrum of heat and light, and the light component (especially near-infrared and red light) provides benefits like photon neuroprotection, decreased inflammation, and mitochondrial impact, which are absent in traditional hot air saunas. Ben Greenfield adds that the light photons can structure water within the vasculature, leading to smoother blood flow and better nitric oxide absorption, further distinguishing infrared from mere heat. The ability to separate and maximize the output of different infrared wavelengths is crucial for these targeted effects.

Connie Zach explains that traditional saunas heat the air, making the user feel hot, whereas infrared saunas bypass the air and directly heat the body by absorbing energy. She cites Dr. Michael Hamblin, a leading expert in photobiomodulation, who emphasizes that infrared is light energy absorbed by the body, not about air temperature. The longest and smoothest wavelengths, which are most easily absorbed, are present immediately upon turning the sauna on. While some prefer a hotter environment, starting at a lower temperature or getting in immediately allows for optimal absorption, particularly for those with compromised health, and can lead to longer, more comfortable sessions. Consistency of use is prioritized over intense heat.

Connie Zach references the 'blood, urine, sweat' study by Dr. Januis, which showed that many toxicants, even those undetectable in blood, could be found in sweat after infrared sauna use. This study was initially motivated by protecting women from environmental toxins before conception. However, she acknowledges that specific research on microplastic detoxification in saunas is still lacking. Ben Greenfield suggests that individuals could conduct N=1 experiments using home salivary microplastic tests before and after a rigorous sauna practice to gather anecdotal evidence.