
Bryan Johnson: Is Sauna Worth the Hype?
There's evidence that sauna is a potential detox and longevity intervention with benefits to heart, metabolism, brain health, and skin. We’re going to put it to the test.
Here’s what you need to know…
POSTED: 5/14/25
Interesting effects from 7 days of sauna (200°F for 20 min). It's early and I'll get more data in the coming weeks so we'll see.
Central systolic blood pressure 103→97 mmHg:
My heart, brain and all major organs are experiencing 5.83% less pressure than a week ago. I started in the lower normal range, now it is even lower in the lowest 2.5-5% for 20-year olds.
Central pulse pressure 28→22 mmHg:
21.43% more flexible aorta and less load on my heart.
Augmentation pressure 2→1 mmHg, and augmentation index 8→6 %
Both indicating further decrease in my arterial stiffness and increase in aortic compliance.
Subendocardial variability ratio SEVR 220-212%
Small downwards shift of 3%, while still in mid normal range reflecting normal heart oxygenation.
How sauna helps achieve these results?
Heat-induced vasodilation and lower sympathetic activity at rest due to repeated heat exposure.
Arterial structure remodeling and increased aortic elasticity.
Confounders to rule out
Change could be due to a small reduction in plasma volume due to repeated heat exposure, will rule out by testing my urine for hydration markers and keeping them stable.
Change can also be within the normal levels of variance for this measurement, this can be ruled out with repeated measurements showing the same trend as I continue my sauna protocol.
These improvements are in line with the strong clinical evidence supporting the cardiovascular protective effects of sauna.
POSTED: 5/14/25
My body sweats 18 oz during a 20 min sauna at 200 °F, with a sodium concentration of 25-39 mg/oz.
A single sauna session flushes 450–700 mg of sodium out of my body. ~30-50% of ideal daily intake.
I measured this because I got intense muscle cramps during sleep after starting sauna and needed to figure out the electrolyte balancing.
These results now inform my sodium sweat profile (everyone is different) and needed fluid intake before and after.
My protocol is to consume 20 oz before and 20 oz after each sauna session, each with 350 mg of sodium, 80 mg of potassium and 24 mg of magnesium. This is a Blueprint concoction that we've sourced and tested ourselves.
I used the Gatorade Sweat Patch for measurement.
POSTED: 5/7/25
0/ How it works
Heat exposure in a sauna puts your body under mild stress, triggering natural repair processes that improve overall health. Finnish dry saunas specifically use controlled heat to stimulate these beneficial responses, including: Repairing and maintaining proteins (heat shock proteins)
+ Improving blood flow and relaxing blood vessels
+ Boosting antioxidant activity
+ Optimizing metabolism
+ Enhancing fitness
+ Reducing inflammation
+ Strengthening immunity
+ Recycling and repairing cells (autophagy)
All these processes combine to give whole-body health benefits.
1/ It protects your heart
Regular sauna use (4–7 times a week, sessions lasting at least 19 minutes) can significantly improve heart health and lower blood pressure. Research shows the more often you sauna, the greater your protection from heart disease:
Heart disease risk:
2–3 times/week → 23% lower risk
4–7 times/week → 48% lower risk
High blood pressure risk (in healthy men aged 42–60):
2–3 times/week → 17% lower risk
4–7 times/week → 47% lower risk
In patients with existing heart failure, using a sauna 5 times a week for 3 weeks improved heart function by nearly 7%, lowered stress hormones by 25%, and reduced heart failure markers by over 20%. Longer and more frequent sauna sessions offer the strongest protection.
2/ It can improve mental health
Regular sauna use can lower your risk of dementia and boost your overall mental health.
+ Better sleep: Over 80% reported improved sleep quality.
+ Reduced pain: 33% experienced less muscle pain.
+ Happier mood: Regular sauna users (1–4 times/week) report feeling happier and less stressed.
+ Lowers dementia risk: lowers by 21% (2–3 times/week) and 48% (4–7 times/week)
+ Lowers psychotic disorder risk: 4–7 times/week → 77% lower risk
3/ Reduces inflammation
Regular sauna use reduces inflammation and can ease autoimmune conditions. Studies in healthy middle-aged men show frequent sauna use lowers systemic inflammation significantly:
2–3 sessions/week: 17% lower inflammation
4–7 sessions/week: 31.5% lower inflammation
These anti-inflammatory benefits grow stronger with increased sauna frequency and are sustained over the long term. Sauna use notably reduces markers like hsCRP, fibrinogen, and white blood cell count, all linked to chronic inflammation.
As a result, regular sauna sessions improve quality of life and ease symptoms in chronic inflammatory and autoimmune diseases, such as rheumatoid arthritis.
4/ It can improve your metabolism
Sauna can improve your body composition, metabolism, and fitness levels.
It has shown:
+ Significant decrease in bad cholesterol (total cholesterol and LDL)
+ Transient significant decrease in blood fat (triglycerides)
+ Small increases in good cholesterol (HDL)
These benefits were seen in young men completing 10 sauna sessions (3 x 15 minutes, 2 min cool-downs in between).
In a low powered study (small sample size with additional limitations), research also showed a 1.07% increase in muscle mass & 7.7% increase in bone mineral density. This is based upon 12 days of high-temperature (100°C) long sauna sessions (5 x 10 min each) across 4 weeks.