#058 Aliquot #2: Q&A Mashup - Sauna

Rhonda Patrick (0:00)

Hi, my friends. Today's episode is our second special Aliquot mashup episode, which features a compilation of sauna related topics taken from several Q&A episodes over the last couple of years. This episode covers many topics related to sauna use, including implications of sauna bathing on risk of pneumonia and respiratory illnesses, finished sauna, humidity, and the immune system, the effects of sauna and hot baths on heat shock proteins, temperature and duration of sauna bathing to obtain the cardiovascular benefits, my personal sauna practices for longevity, comparing the efficacy and safety of infrared saunas versus traditional saunas, heat stress response from various types of heat stress modalities, including hot baths, how whole body hyperthermia similar to sauna improves drug resistant depression, how sauna use mimics moderate cardiovascular exercise, time, temperature and frequency to get longevity benefits and heat shock proteins, sauna use while fasting. It sounds stressful, but someone asked about it. So we talk about it, whether or not sauna use is helpful for tension headaches and so much more. This is a special preview of the Aliquot Members Only Podcast for a full timeline with time codes for each topic and access to the entire episode. Head over to foundmyfitness.com forward slash aliquot. That's A-L-I-Q-U-O-T, aliquot. If you are a premium member, you can also find this entire episode with a timeline on your private podcast feed. Now on to the aliquot. Hope you guys enjoy. Some of the other things I'm trying to do are the sauna, four to seven times a week, 20 minutes at at least 174 degrees Fahrenheit. So I've shared this study on social media about the sauna reducing the risk for chronic acute respiratory illnesses, including pneumonia. So men who use the sauna three times a week were 27% less likely to develop pneumonia than those who did the sauna once a week. And those that used it four to seven times a week were 41% less likely to develop pneumonia, and this was after adjusting for a million other potential confounding factors, including asthma, physical activity, social economic status, LDL levels, hypertension, smoking, just a lot of other things that could possibly influence the data. There's other studies that have shown that the sauna bathing has been shown to reduce the incidence of common colds. Now, I'm writing a review article on the sauna, which I'm hoping to submit in the next month or two. So I wrote a section on the lungs and respiratory function. So I was kind of diving back in the literature, sometimes back into the 80s or even sometimes further. But there's some interesting studies out there showing that intervention trials with the sauna was able to reduce the incidence of common colds in people that did the sauna once a week. And this was a trial that was done. It was a six month long trial, so it was quite long. And it actually took three months of doing this on a one to two times a week before there was an effect on reducing the incidence of common cold. So it wasn't a sort of immediate thing. It took some time.

Other studies have shown, and these again are older studies, they've shown that that frequent sauna use may decrease pulmonary congestion and lead to other improvements in lung function, including vital capacity, tidal volume, minute ventilation and force expiratory volume.

Another study using not typical finished sauna, but way on therapy, which is infrared sauna, was also shown to improve lung function in people with chronic obstructive pulmonary disease or COPD.

So a sort of interesting thing is that many, but not all of those studies were out of Finland or were using a finished sauna, which typically is a humid sauna. So in Finland, they're often throwing water over these hot rocks and they're creating steam and they're increasing the humidity. And the reason I find this interesting is because there have been some studies. So there have been quite a few studies showing that viruses in general, influenza particularly is a virus that's studied quite often, that influenza viruses transmit less effectively in humid conditions. In other words, in dry conditions, they're able to better, they have a better transmission rate. They are not.

But that's not what I found most interesting. That's sort of been known.

And it's thought that's one contributing factor among many other contributing factors as to why viruses like influenza virus and respiratory viruses seem to circulate more during dry or winter months, right?

As opposed to the summer months when it's more humid. The other interesting factor comes from an animal study. And the animal study basically took two groups of animals and they changed the humidity within the animals' cages and they exposed them to influenza. And what they found was that the animals that were in the low humidity cages, there was pretty profound effects on the immune system. So lower humidity prevented cilia from removing viral particles and also mucus. Low humidity reduced the ability of airway cells to repair damage caused by the virus in the lungs. And low humidity prevented signaling proteins like interferons that are released by cells that are infected by viruses to basically alert nearby cells that viruses are here and to kind of up their immune response. So there was a variety of ways in which low humidity seemed to give viruses an advantage, not by allowing viruses to transmit better, but by literally affecting the host immune function, right? So I found that very interesting, particularly with the sauna data where there seems to be a pretty robust effect on preventing pneumonia and other respiratory illnesses and effects on lungs, and a lot of the times the saunas used do have a humid. In those studies, they were finished saunas oftentimes are humid.