I was convinced by Rhonda Patrick’s research that saunas were beneficial for healthy aging in her Ferriss podcast. In this podcast, she interviews a Finnish expert on the topic. I’ve been incorporating saunas into my routine, and though I don’t find them “blissful” as everyone else seems to, I can see why they might have a positive hormetic effect. All that sweating has to be good, right??
The podcast here.
Transcript and time prompts here. (Why don’t all podcasts have these?? So helpful!)
Often when I talk about sauna, I may refer sometimes to animal studies especially when it comes to molecular evidence, but it is Dr. Laukkanen’s lab that actually makes the single most convincing case that sauna use has real benefits . It is his research that has shown that long-term sauna use appears to reduce heart-related mortality, but even more surprisingly, also may have a strong effect on what is known as all-cause mortality, which literally means death from all causes… which sounds a whole lot like longevity if you think about it.
Moreover, since this conversation was recorded, Dr. Laukkanen’s lab released yet another publication which showed really strong associations with a reduction of risk of dementia and Alzheimer’s disease by 66% and 65% respectively at 20-year follow-up, which further strengthens the case that sauna therapy, more than being relaxing, may be a great tool for even improving healthspan.
In both the studies showing reduced memory illness and reduced all-cause mortality the effect follows a dose-response relationship with the group showing the strongest reductions in risk by frequenting a sauna at least 4 times per week for at least 20 minutes at 174 degrees fahrenheit, or 79 degrees celsius.
In fact, one of the more interesting observations made by Dr. Laukkanen in this podcast is that time spent in the sauna appears to be a very important factor… with shorter sauna session having a much less robust effect.
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In this almost 25-minute episode, we talk about…
- 00:00:37 – The association between sauna use and fatal cardiovascular outcomes
- 00:00:37 – The inverse association between cardiovascular-related deaths and all-cause deaths.
- 00:02:00 – How men that used the sauna 2-3 times per week had a 27% lower cardiovascular related mortality than men that used the sauna 1 time per week
- 00:02:15 – How men that used the sauna 4-7 times per week had a 50% lower cardiovascular-related mortality than men that used the sauna one time per week.
- 00:02:50 – The confounding factors Dr. Laukkanen and his colleagues had to adjust for, such as physical exercise, cholesterol, obesity, smoking, alcohol consumption, socioeconomic status.
- 00:03:26 – The various types of cardiac-related deaths their reductions were shown in, including coronary artery disease, sudden cardiac death and more.
- 00:05:00 – How one of the major mechanisms by which sauna use improves heart health is by reducing blood pressure and incident hypertension.
- 00:05:40 – The mechanisms by which the sauna lowers blood pressure, which can occur via balancing of the autonomic nervous system, improvements in blood vessel function, decreases in arterial stiffness and compliance of arteries.
- 00:06:17 – The increases in heart rate seen with sauna use that make it similar to moderate aerobic exercise in some ways (up to 150 beats/min!).
- 00:06:56 – How time spent in the sauna was one of the more important factors for risk reduction with at least 20 minutes per session in a 174 F (79C) 4-7 times per week being a “sweet spot.”
- 00:09:29 – The inverse, dose-response relationship between sauna use and all-cause mortality: 24% for 2-3 times per week, 40% for 4-7 times.
- 00:10:00 – His newest study that now shows a reduction in risk in a similar dose-response fashion for dementia and Alzheimer’s disease by around 65% for the most frequent sauna users.
- 00:10:18 – The way sauna use increases heat shock proteins which repair damaged proteins and prevent protein aggregates and how this could end up being at least one potential molecular mechanism at play.
- 00:13:03 – How sauna use increases growth hormone by 200-330%.
- 00:14:10 – The patterns of sauna use and especially whether to sauna before or after you weight train.
- 00:15:55 – The effect of sauna on mood which may be from improvements in cardiorespiratory fitness and possibly endorphins as well.
- 00:18:39 – How sauna improves heart rate variability.
- 00:20:04 – Cold-water immersion after sauna and a few cautionary words for extreme contrast therapy in people with a pre-existing heart condition that is currently unstable.
That’s it for now! Make sure to give Dr. Laukkanen a tweet (@LaukkanenJari) if you’re into that sort of thing.