The TL;DR
Regular heat exposure through sauna bathing is one of the most well-documented interventions for reducing cardiovascular mortality and all-cause death risk. The landmark Finnish studies by Laukkanen et al. demonstrate a clear dose-response relationship: individuals using saunas 4-7 times per week had a 40% lower risk of all-cause mortality compared to once-weekly users. Heat stress activates protective heat shock proteins, improves cardiovascular function, and may reduce dementia risk. Evidence-based protocols suggest 15-20 minutes at 80-100C (176-212F) for Finnish saunas, 3-7 sessions weekly.
Accessibility Level
Level 2 (Optimization): Heat exposure requires access to a sauna, steam room, or hot bath. While gym memberships often include sauna access, dedicated home saunas represent a more significant investment. Master exercise and dietary foundations before prioritizing this intervention, though the cardiovascular benefits are substantial enough to warrant early adoption if accessible.
The Science of Heat Exposure and Longevity
Types of Heat Exposure
Heat stress can be induced through several modalities, each with distinct characteristics:
Finnish Dry Sauna (Traditional) The most extensively studied form of heat exposure, Finnish saunas operate at high temperatures (80-100C / 176-212F) with low humidity (10-20%). The Kuopio Ischemic Heart Disease Risk Factor Study (KIHD), which forms the basis of most longevity evidence, specifically studied traditional Finnish sauna use (Laukkanen et al., 2015). Heat transfer occurs primarily through convection from hot air and radiation from heated surfaces.
Infrared Sauna Infrared saunas operate at lower air temperatures (45-60C / 113-140F) but use infrared radiation to directly heat body tissues. While less studied than Finnish saunas, infrared saunas have demonstrated benefits for cardiovascular function in heart failure patients (Beever, 2009) and may be better tolerated by those who find traditional saunas too intense. However, the lower temperatures may not provide equivalent heat shock protein activation.
Steam Rooms Steam rooms use high humidity (100%) at lower temperatures (40-50C / 104-122F). The moist heat promotes sweating and may have respiratory benefits, but the evidence base for longevity outcomes is less robust than for dry sauna. The perception of heat is greater due to humidity preventing sweat evaporation.
Hot Baths and Hot Tubs Hot water immersion (40-42C / 104-108F) provides heat stress through a different mechanism than sauna. Japanese research on traditional hot spring bathing (onsen) has shown associations with reduced cardiovascular mortality (Hayasaka et al., 2010). Hot baths may be more accessible than sauna for many individuals.
Evidence Hierarchy
The strongest longevity evidence comes from Finnish dry sauna studies. While other modalities likely provide benefits through similar mechanisms, protocols and outcomes may differ. When possible, prioritize dry sauna exposure or ensure sufficient core temperature elevation with alternative modalities.
Physiological Mechanisms
Heat exposure triggers a coordinated stress response that produces numerous adaptations beneficial for longevity:
Heat Shock Proteins (HSPs)
Heat shock proteins are molecular chaperones that help maintain protein structure and prevent aggregation under stress conditions. Heat exposure dramatically upregulates HSP expression, particularly HSP70 and HSP90 (Kregel, 2002).
HSPs provide protection through several mechanisms:
- Protein quality control: HSPs refold damaged proteins and target irreparable proteins for degradation, preventing the accumulation of dysfunctional proteins associated with aging and neurodegeneration (Morimoto, 2008).
- Anti-apoptotic effects: HSP70 inhibits programmed cell death pathways, protecting cells from stress-induced damage (Garrido et al., 2001).
- Anti-inflammatory signaling: HSPs modulate immune responses and reduce chronic inflammation (Krause et al., 2015).
- Cardiac protection: HSP induction protects cardiomyocytes from ischemia-reperfusion injury (Locke & Tanguay, 1996).
Regular heat exposure creates a preconditioned state where cells have elevated baseline HSP levels, providing ongoing protection against various stressors.
Cardiovascular Adaptation
Heat exposure produces profound cardiovascular effects that mimic aspects of aerobic exercise (Laukkanen et al., 2018):
- Increased heart rate: Heart rate rises to 100-150 bpm during sauna, comparable to moderate-intensity exercise.
- Vasodilation: Peripheral blood vessels dilate to dissipate heat, reducing systemic vascular resistance.
- Blood pressure reduction: Acute vasodilation lowers blood pressure during and after sauna. Regular use is associated with reduced hypertension risk (Zaccardi et al., 2017).
- Improved endothelial function: Heat stress stimulates nitric oxide production, improving vascular health (Imamura et al., 2001).
- Cardiac output increase: The cardiovascular system works harder to distribute blood to the periphery for cooling, providing a training stimulus.
Growth Hormone Release
Sauna exposure acutely elevates growth hormone levels. A study by Leppaluoto et al. (1986) found that two 20-minute sauna sessions at 80C separated by a 30-minute cooling period increased growth hormone levels 2-5 fold. More recent research suggests the magnitude of growth hormone release depends on temperature, duration, and individual factors.
While growth hormone has anabolic effects and supports tissue repair, chronic elevation is not clearly beneficial for longevity. The acute, pulsatile release from sauna differs from pathological chronic elevation and may provide benefits without downsides (Berryman et al., 2008).
FOXO3 Activation
Heat stress activates FOXO3, a transcription factor strongly associated with longevity in genetic studies. Variants in FOXO3 are among the most replicated genetic associations with human longevity (Willcox et al., 2008). FOXO3 activation promotes:
- Autophagy: Cellular cleaning and recycling processes
- Antioxidant defense: Upregulation of superoxide dismutase and catalase
- DNA repair: Enhanced maintenance of genomic integrity
- Stress resistance: Broad-spectrum protection against cellular damage
Endorphin Release and Mood Effects
Heat stress triggers endogenous opioid release, contributing to the euphoric feeling often reported after sauna sessions. Regular heat exposure may support mental health through these mechanisms and through downstream effects on inflammation, which is increasingly recognized as a contributor to depression (Miller & Raison, 2016).
The Protocol
Finnish Sauna Protocol
Based on the Laukkanen studies and Finnish sauna traditions:
| Parameter | Recommendation |
|---|---|
| Temperature | 80-100C (176-212F) |
| Duration per session | 15-20 minutes |
| Frequency | 4-7 sessions per week for optimal benefits |
| Minimum frequency | 2-3 sessions per week for meaningful benefits |
| Time of day | Evening preferred (may enhance sleep) |
| Hydration | 2-4 glasses of water before and after |
Session Structure:
-
Pre-session: Ensure adequate hydration. Shower before entering sauna for hygiene. Remove jewelry and electronics.
-
During session: Sit on upper bench for maximum temperature (heat rises). Breathe normally. Listen to your body; if you feel dizzy, nauseous, or unwell, exit immediately.
-
Cooling period: After exiting, allow 2-5 minutes for body temperature to normalize. A cool (not cold) shower can aid cooling. Some traditions include brief cold exposure (see contrast therapy below).
-
Recovery: Rest for 10-15 minutes before repeating or ending session. Rehydrate with water and electrolytes.
Progressive Adaptation:
For those new to sauna:
| Week | Duration | Temperature | Frequency |
|---|---|---|---|
| 1-2 | 5-10 min | Lower bench (cooler) | 2-3x/week |
| 3-4 | 10-15 min | Middle bench | 3-4x/week |
| 5+ | 15-20 min | Upper bench | 4-7x/week |
Practical Considerations
- Evening sauna 1-2 hours before bed may improve sleep quality through the subsequent drop in core temperature
- Avoid sauna immediately after heavy meals
- Alcohol and sauna is dangerous and should be strictly avoided
- If recovering from intense exercise, wait 2-4 hours before sauna to allow initial inflammatory signaling
Infrared Sauna Protocol
| Parameter | Recommendation |
|---|---|
| Temperature | 45-60C (113-140F) |
| Duration | 30-45 minutes (longer due to lower temperature) |
| Frequency | 3-5 sessions per week |
Infrared saunas may be preferred by those who find traditional saunas overwhelming, have respiratory sensitivities, or prefer lower intensity exposure. However, to achieve equivalent heat stress and HSP activation, longer durations and consistent core temperature elevation are important.
Hot Bath Protocol
For those without sauna access, hot baths can provide meaningful heat stress:
| Parameter | Recommendation |
|---|---|
| Temperature | 40-42C (104-108F) |
| Duration | 15-20 minutes immersed to shoulders |
| Frequency | Daily possible; 4-7x/week optimal |
A study by Faulkner et al. (2017) found that regular hot water immersion improved cardiovascular function and reduced blood pressure in sedentary individuals, with effects comparable to exercise. Ensure the water remains hot enough to maintain heat stress throughout the session.
Evidence for Longevity Benefits
The Laukkanen Studies: Cardiovascular and All-Cause Mortality
The most compelling evidence for sauna and longevity comes from the Kuopio Ischemic Heart Disease Risk Factor (KIHD) study, a prospective cohort study following 2,315 middle-aged Finnish men for an average of 20+ years.
All-Cause Mortality (Laukkanen et al., 2015)
The landmark study published in JAMA Internal Medicine found a striking dose-response relationship between sauna frequency and mortality:
| Sauna Frequency | Relative Risk of All-Cause Mortality | Absolute Risk Reduction |
|---|---|---|
| 1x/week (reference) | 1.00 | - |
| 2-3x/week | 0.76 (24% reduction) | Significant |
| 4-7x/week | 0.60 (40% reduction) | Highly significant |
Longer duration also provided additional benefit: those spending more than 19 minutes per session had lower mortality than those spending less than 11 minutes.
Cardiovascular Disease Mortality (Laukkanen et al., 2015)
The same study found even more pronounced effects for cardiovascular mortality:
| Sauna Frequency | Risk of Sudden Cardiac Death | Risk of Fatal CVD |
|---|---|---|
| 1x/week | Reference | Reference |
| 2-3x/week | 22% reduction | 23% reduction |
| 4-7x/week | 63% reduction | 48% reduction |
Fatal Coronary Heart Disease (Laukkanen et al., 2015)
For fatal coronary heart disease specifically, the risk reduction was 23% for 2-3 sessions per week and 48% for 4-7 sessions per week compared to once-weekly use.
Key Insight
The magnitude of mortality reduction observed in the Laukkanen studies rivals the most effective pharmaceutical interventions and is comparable to regular exercise. These findings have been replicated and extended in subsequent publications from the same cohort.
Hypertension Risk (Zaccardi et al., 2017)
Analysis of the KIHD cohort found that frequent sauna bathing was associated with reduced risk of developing hypertension:
- 2-3 sessions/week: 24% reduced risk
- 4-7 sessions/week: 46% reduced risk
Given that hypertension is a major risk factor for cardiovascular disease and stroke, this finding helps explain the cardiovascular mortality reductions.
Dementia and Alzheimer’s Disease (Laukkanen et al., 2017)
Remarkably, frequent sauna use was also associated with reduced dementia risk in the KIHD cohort:
| Sauna Frequency | Risk of Dementia | Risk of Alzheimer’s Disease |
|---|---|---|
| 1x/week | Reference | Reference |
| 2-3x/week | 22% reduction | 20% reduction |
| 4-7x/week | 66% reduction | 65% reduction |
The mechanisms may include improved cardiovascular health (vascular contributions to dementia), heat shock protein-mediated clearance of misfolded proteins (including amyloid-beta), and reduced inflammation.
Respiratory Benefits (Kunutsor et al., 2017)
The KIHD cohort also showed associations between sauna bathing and reduced risk of respiratory diseases, including pneumonia. Men using sauna 4+ times weekly had 37% lower risk of respiratory disease compared to once-weekly users.
Detoxification Through Sweat
Sweat produced during heat exposure contains various compounds beyond water and electrolytes, including some environmental toxins and heavy metals (Genuis et al., 2011). While the clinical significance of this excretion pathway is debated, research suggests that sweating may contribute to elimination of:
- Heavy metals (arsenic, cadmium, lead, mercury)
- Bisphenol A (BPA)
- Phthalates
- Some persistent organic pollutants
However, the kidneys and liver remain the primary detoxification organs, and claims about sauna “detox” should be viewed with appropriate skepticism. The documented longevity benefits are more likely attributable to cardiovascular, anti-inflammatory, and cellular stress response mechanisms than detoxification per se.
Evidence Matrix
| Source | Verdict | Notes |
|---|---|---|
| Laukkanen KIHD Studies | Strong Evidence | 40% mortality reduction with 4-7x/week use; dose-response relationship |
| Peter Attia (Outlive) | Recommends | Cites cardiovascular and neurological benefits; suggests 4x/week minimum |
| Rhonda Patrick | Strongly Recommends | Detailed mechanistic explanations; emphasis on HSP activation |
| Huberman Lab | Recommends | Discussion of growth hormone, HSP, and protocol optimization |
| Andrew Steele (Ageless) | Recommends | Notes association data strength; mentions need for RCT confirmation |
| Valter Longo | Limited Discussion | Less emphasis compared to dietary interventions |
Key Studies:
- Laukkanen et al. (2015): Sauna bathing inversely associated with fatal CVD and all-cause mortality in KIHD cohort
- Laukkanen et al. (2017): 66% reduction in dementia risk with 4-7x/week sauna use
- Zaccardi et al. (2017): Frequent sauna bathing associated with reduced hypertension risk
- Kunutsor et al. (2017): Inverse association between sauna use and respiratory diseases
- Beever (2009): Infrared sauna benefits for heart failure patients
Safety Considerations and Contraindications
General Safety
Sauna bathing is remarkably safe for most individuals. A review of Finnish data found that sudden cardiac death in saunas was rare (approximately 2 per 100,000 person-years) and typically occurred in individuals with pre-existing cardiovascular disease, often in conjunction with alcohol use (Kunutsor et al., 2018).
Safe Practices:
- Stay hydrated before, during, and after sauna
- Never combine sauna with alcohol consumption
- Exit immediately if feeling dizzy, nauseous, or unwell
- Start with shorter durations and lower temperatures if new to sauna
- Allow adequate cooling time between sessions
- Avoid sauna if acutely ill or febrile
Contraindications
Absolute Contraindications:
- Unstable angina
- Recent myocardial infarction (within 4-8 weeks without clearance)
- Severe aortic stenosis
- Symptomatic heart failure (unless specifically cleared by cardiologist)
- Uncontrolled hypertension
- Active infection or fever
Relative Contraindications (consult physician):
- Stable cardiovascular disease (may actually benefit but requires clearance)
- Orthostatic hypotension
- Autonomic neuropathy
- Pregnancy (traditional advice is to avoid, though evidence is limited)
- Taking medications that affect sweating or temperature regulation
Medication Considerations:
- Beta-blockers may blunt heart rate response but do not preclude sauna use
- Diuretics increase dehydration risk
- Vasodilators may cause excessive blood pressure drop
- Drugs affecting sweating (anticholinergics) may impair thermoregulation
Medical Clearance
Individuals with known cardiovascular disease should consult their physician before beginning regular sauna use. However, the KIHD data suggest that even individuals with cardiovascular risk factors may benefit from sauna bathing when practiced safely.
Hydration and Electrolyte Considerations
Fluid Loss: A single sauna session can produce 0.5-1.0 kg of sweat loss (500-1000 mL of fluid). Repeated sessions without adequate rehydration can lead to significant dehydration.
Hydration Protocol:
- Consume 500 mL (2 glasses) of water 1-2 hours before sauna
- Drink water during session if desired (though some traditions advise against)
- Consume 500-750 mL water within 30 minutes after sauna
- Monitor urine color: pale yellow indicates adequate hydration
Electrolyte Replacement: Sweat contains sodium, potassium, magnesium, and other electrolytes. For single sessions, water is usually sufficient. For extended or multiple sessions:
- Consider electrolyte supplementation (pinch of salt in water, electrolyte tablets)
- Consume electrolyte-rich foods after sauna (fruits, vegetables)
- Those on low-sodium diets should be particularly attentive to salt replacement
Contrast Therapy: Combining Heat and Cold Exposure
The combination of heat exposure with cold exposure (contrast therapy) is a traditional practice in many cultures, including Finnish sauna followed by cold lake immersion and Russian banya followed by cold plunge.
Proposed Benefits
Vascular Training: Alternating vasodilation (heat) and vasoconstriction (cold) may improve vascular flexibility and endothelial function. The repeated cycling between these states provides a form of vascular exercise (Ihsan et al., 2016).
Enhanced Recovery: Some athletes use contrast therapy for recovery, though evidence is mixed. The alternating temperatures may promote blood flow and reduce perceived fatigue (Cochrane, 2004).
Norepinephrine Release: Cold exposure potently increases norepinephrine, enhancing alertness and mood. Combined with the relaxation effects of sauna, contrast therapy may provide a unique psychophysiological state (Shevchuk, 2008).
Contrast Therapy Protocol
A typical contrast therapy session:
- Heat phase: 15-20 minutes in sauna at 80-100C
- Cold phase: 1-3 minutes cold shower, cold plunge (10-15C / 50-59F), or cold lake immersion
- Rest phase: 5-10 minutes at room temperature
- Repeat: 2-3 cycles total
Order Matters
Ending on cold exposure tends to create an invigorating, alert state. Ending on heat exposure tends to promote relaxation and may be better before sleep. Choose the order based on desired outcome.
Considerations for Muscle Adaptation
Cold exposure immediately after resistance training may blunt muscle hypertrophy by interfering with inflammatory signaling necessary for adaptation (Roberts et al., 2015). If using contrast therapy:
- Avoid cold exposure within 2-4 hours after strength training
- Heat exposure alone after training may enhance recovery without blunting adaptation
- Cold exposure is fine after aerobic training or on non-training days
Measuring Success
Subjective Markers
- Improved sense of well-being and relaxation
- Better sleep quality, particularly when sauna is taken in evening
- Enhanced recovery from exercise
- Reduced muscle soreness
- Mental clarity and mood improvement
- Improved cold tolerance over time
Objective Markers
Cardiovascular:
| Marker | Assessment | Expected Change |
|---|---|---|
| Resting heart rate | Morning measurement | May decrease over time |
| Blood pressure | Home monitoring | Reduction, especially in those with elevated BP |
| HRV | Wearable device | May improve with consistent practice |
Metabolic and Inflammatory:
| Marker | Assessment | Expected Change |
|---|---|---|
| hs-CRP | Blood work | May decrease with regular practice |
| Fasting glucose | Blood work | Improved insulin sensitivity possible |
| Lipid profile | Blood work | Modest improvements reported |
Connected Concepts
Foundational Links
- Exercise: Sauna provides cardiovascular stress similar to moderate exercise; complements training programs
- Sleep: Evening sauna may improve sleep through core temperature manipulation
- Stress and Mindset: Heat exposure is a controlled stressor that may build resilience
Optimization Links
- Cold Exposure: Contrast therapy combines both modalities; different but complementary mechanisms
- Fasting: Both activate stress response pathways (FOXO3, autophagy)
Concepts
- Heat Shock Proteins: Key molecular mechanism of heat exposure benefits
- Autophagy: Cellular cleaning processes activated by heat stress
- Inflammation: Regular heat exposure reduces chronic inflammatory markers
- Mitochondria: Heat stress may promote mitochondrial biogenesis
Biomarkers
- HRV: Indicator of autonomic adaptation to heat stress
- Resting Heart Rate: May decrease with cardiovascular adaptation from regular sauna
- Blood Pressure: Sauna associated with reduced hypertension risk
Common Pitfalls
Mistakes to Avoid
- Combining sauna with alcohol: Alcohol impairs thermoregulation and increases cardiovascular risk. This combination is responsible for most sauna-related adverse events.
- Inadequate hydration: Failure to replace fluids and electrolytes can lead to dehydration, electrolyte imbalances, and hypotension.
- Ignoring warning signs: Dizziness, nausea, and excessive discomfort are signals to exit immediately.
- Starting too aggressively: New users should begin with shorter durations and lower temperatures to allow adaptation.
- Expecting immediate results: The longevity benefits come from consistent practice over months and years.
- Using sauna immediately after heavy meals: Blood flow to the skin competes with digestive demands; wait 1-2 hours after eating.
- Cold exposure immediately after strength training: This may blunt muscle adaptation. Separate by 2-4 hours.
- Assuming infrared is equivalent: While beneficial, lower temperatures may not provide the same HSP activation as traditional sauna.
- Neglecting underlying conditions: Those with cardiovascular disease should obtain medical clearance before beginning.
Implementation Checklist
Week 1-2: Introduction
- Identify sauna access (gym, spa, or home unit)
- Start with 2-3 sessions per week
- Begin with 10-15 minutes at lower temperature or lower bench
- Establish hydration routine (water before and after)
- Note subjective response (tolerance, sleep effects)
Week 3-4: Adaptation
- Increase duration to 15-20 minutes
- Move to higher bench position (hotter)
- Increase frequency toward 4 sessions per week
- Experiment with timing (morning vs. evening)
- Add electrolyte replacement if needed
Week 5+: Optimization
- Achieve 4-7 sessions per week if tolerated and accessible
- Consistent 15-20 minute sessions at 80-100C
- Consider contrast therapy (ending with cold exposure)
- Track cardiovascular markers (resting HR, BP, HRV)
- Maintain practice as long-term lifestyle habit
Research Limitations and Future Directions
While the evidence for sauna and longevity is compelling, several limitations warrant acknowledgment:
Observational Nature: The KIHD studies are observational, meaning causation cannot be definitively established. Frequent sauna users may differ in other ways (socioeconomic status, overall health consciousness, other behaviors) that contribute to their longevity. However, the dose-response relationship and biological plausibility strengthen the case for causation.
Population Specificity: Most longevity data comes from Finnish men. While there is no biological reason to expect different effects in women or other populations, direct evidence is more limited. Recent extensions of the KIHD data have included women with similar findings.
Lack of RCTs for Mortality: No randomized controlled trial has examined sauna use and mortality outcomes (such a trial would be impractical given the duration needed). The evidence relies on observational cohorts supplemented by mechanistic studies.
Optimal Protocol Uncertainty: While 4-7 sessions per week at 80-100C for 15-20 minutes appears optimal based on KIHD data, the ideal protocol may vary by individual factors (age, health status, goals).
Infrared Sauna Evidence Gap: The longevity data specifically applies to Finnish dry sauna. Infrared sauna benefits are plausible but less well-documented for long-term outcomes.
Further Reading
Books:
- “Outlive” by Peter Attia: Discussion of sauna in the context of longevity medicine
- “Ageless” by Andrew Steele: Overview of longevity interventions including heat exposure
Podcasts:
- FoundMyFitness (Rhonda Patrick): Detailed episodes on sauna mechanisms and protocols
- Huberman Lab: Episodes on deliberate heat exposure and hormesis
- The Drive (Peter Attia): Discussion of Finnish sauna research
Research:
- KIHD Study publications (JAMA Internal Medicine, Age and Ageing)
- Rhonda Patrick’s sauna report at FoundMyFitness.com
- Finnish Sauna Society publications
References
Beever, R. (2009). Far-infrared saunas for treatment of cardiovascular risk factors: summary of published evidence. Canadian Family Physician, 55(7), 691-696.
Berryman, D. E., Christiansen, J. S., Johannsson, G., Thorner, M. O., & Kopchick, J. J. (2008). Role of the GH/IGF-1 axis in lifespan and healthspan: lessons from animal models. Growth Hormone & IGF Research, 18(6), 455-471.
Cochrane, D. J. (2004). Alternating hot and cold water immersion for athlete recovery: a review. Physical Therapy in Sport, 5(1), 26-32.
Faulkner, S. H., Jackson, S., Fatania, G., & Leicht, C. A. (2017). The effect of passive heating on heat shock protein 70 and interleukin-6: a possible treatment tool for metabolic diseases? Temperature, 4(3), 292-304.
Garrido, C., Gurbuxani, S., Ravagnan, L., & Kroemer, G. (2001). Heat shock proteins: endogenous modulators of apoptotic cell death. Biochemical and Biophysical Research Communications, 286(3), 433-442.
Genuis, S. J., Birkholz, D., Rodushkin, I., & Beesoon, S. (2011). Blood, urine, and sweat (BUS) study: monitoring and elimination of bioaccumulated toxic elements. Archives of Environmental Contamination and Toxicology, 61(2), 344-357.
Hayasaka, S., Shibata, Y., Noda, T., Goto, Y., & Ojima, T. (2010). Bathing and mortality among Japanese older adults. Journal of Epidemiology, 20(5), 383-387.
Ihsan, M., Watson, G., & Abbiss, C. R. (2016). What are the physiological mechanisms for post-exercise cold water immersion in the recovery from prolonged endurance and intermittent exercise? Sports Medicine, 46(8), 1095-1109.
Imamura, M., Biro, S., Kihara, T., Yoshifuku, S., Takasaki, K., Otsuji, Y., Minagoe, S., Toyama, Y., & Tei, C. (2001). Repeated thermal therapy improves impaired vascular endothelial function in patients with coronary risk factors. Journal of the American College of Cardiology, 38(4), 1083-1088.
Krause, M., Ludwig, M. S., Heck, T. G., & Takahashi, H. K. (2015). Heat shock proteins and heat therapy for type 2 diabetes: pros and cons. Current Opinion in Clinical Nutrition and Metabolic Care, 18(4), 374-380.
Kregel, K. C. (2002). Heat shock proteins: modifying factors in physiological stress responses and acquired thermotolerance. Journal of Applied Physiology, 92(5), 2177-2186.
Kunutsor, S. K., Laukkanen, T., & Laukkanen, J. A. (2017). Sauna bathing reduces the risk of respiratory diseases: a long-term prospective cohort study. European Journal of Epidemiology, 32(12), 1107-1111.
Kunutsor, S. K., Khan, H., Laukkanen, T., & Laukkanen, J. A. (2018). Joint associations of sauna bathing and cardiorespiratory fitness on cardiovascular and all-cause mortality risk: a long-term prospective cohort study. Annals of Medicine, 50(2), 139-146.
Laukkanen, T., Khan, H., Zaccardi, F., & Laukkanen, J. A. (2015). Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Internal Medicine, 175(4), 542-548.
Laukkanen, T., Kunutsor, S., Kauhanen, J., & Laukkanen, J. A. (2017). Sauna bathing is inversely associated with dementia and Alzheimer’s disease in middle-aged Finnish men. Age and Ageing, 46(2), 245-249.
Laukkanen, J. A., Laukkanen, T., & Kunutsor, S. K. (2018). Cardiovascular and other health benefits of sauna bathing: a review of the evidence. Mayo Clinic Proceedings, 93(8), 1111-1121.
Leppaluoto, J., Huttunen, P., Hirvonen, J., Vaananen, A., Tuominen, M., & Vuori, J. (1986). Endocrine effects of repeated sauna bathing. Acta Physiologica Scandinavica, 128(3), 467-470.
Locke, M., & Tanguay, R. M. (1996). Increased HSF activation in muscles with a high constitutive Hsp70 expression. Cell Stress & Chaperones, 1(3), 189-196.
Miller, A. H., & Raison, C. L. (2016). The role of inflammation in depression: from evolutionary imperative to modern treatment target. Nature Reviews Immunology, 16(1), 22-34.
Morimoto, R. I. (2008). Proteotoxic stress and inducible chaperone networks in neurodegenerative disease and aging. Genes & Development, 22(11), 1427-1438.
Roberts, L. A., Raastad, T., Markworth, J. F., Figueiredo, V. C., Egner, I. M., Shield, A., Cameron-Smith, D., Coombes, J. S., & Peake, J. M. (2015). Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. Journal of Physiology, 593(18), 4285-4301.
Shevchuk, N. A. (2008). Adapted cold shower as a potential treatment for depression. Medical Hypotheses, 70(5), 995-1001.
Willcox, B. J., Donlon, T. A., He, Q., Chen, R., Grove, J. S., Yano, K., Masaki, K. H., Willcox, D. C., Rodriguez, B., & Curb, J. D. (2008). FOXO3A genotype is strongly associated with human longevity. Proceedings of the National Academy of Sciences, 105(37), 13987-13992.
Zaccardi, F., Laukkanen, T., Willeit, P., Kunutsor, S. K., Kauhanen, J., & Laukkanen, J. A. (2017). Sauna bathing and incident hypertension: a prospective cohort study. American Journal of Hypertension, 30(11), 1120-1125.
Last updated: 2026-01-01