TLDR

The research on saunas and cold plunges fits on one page.

We rated 54 claims. These 14 ideas hold up well enough to act on, and each one comes with a thing to try.

These findings about heat hold up

Heat · 01

58%

lower hazard of cardiovascular death for Finnish men who were fit and bathed often

Frequent sauna bathers died of heart disease less often, and fit bathers did best.

In a Finnish study of 2,315 men followed for about 20 years, those who took four to seven saunas a week died of heart disease at about half the rate of once-a-week bathers.Source 1 · Cohort studyAssociation Between Sauna Bathing and Fatal Cardiovascular and All-Cause Mortality EventsLaukkanen T, Khan H, Zaccardi F, et al.. JAMA Internal Medicine, 2015.Read the paper ↗PubMed ↗ With longer follow-up the gap narrowed, and it disappeared in the fittest men.Source 2 · Cohort studyInflammation, sauna bathing, and all-cause mortality in middle-aged and older Finnish men: a cohort studyKunutsor SK, Jae SY, Kurl S, et al.. European Journal of Epidemiology, 2022.Read the paper ↗PubMed ↗Source 3 · Cohort studyJoint associations of sauna bathing and cardiorespiratory fitness on cardiovascular and all-cause mortality risk: a long-term prospective cohort studyKunutsor SK, Khan H, Laukkanen T, et al.. Annals of Medicine, 2018.Read the paper ↗PubMed ↗

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Build a sauna habit you'll keep, and keep exercising. Men who were fit and bathed often had a 58% lower hazard of cardiovascular death than men who were neither.Source 3 · Cohort studyJoint associations of sauna bathing and cardiorespiratory fitness on cardiovascular and all-cause mortality risk: a long-term prospective cohort studyKunutsor SK, Khan H, Laukkanen T, et al.. Annals of Medicine, 2018.Read the paper ↗PubMed ↗

On Sauna MonthlyFinns made the daily sauna a habit

Heat · 02

−8 mmHg

extra drop in systolic pressure when a sauna followed each workout

A sauna after exercise added to the workout's effect on blood pressure.

In an eight-week trial, people who followed each workout with 15 minutes in a sauna ended with systolic pressure 8 mmHg lower than people who only exercised.Source 4 · Randomized trialEffects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trialLee E, Kolunsarka I, Kostensalo J, et al.. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2022.Read the paper ↗PubMed ↗ Heat on its own has shown smaller lasting drops or none.Source 5 · Meta-analysisHeat thermotherapy to improve cardiovascular function and cardiometabolic health: A systematic review and meta‐analysisPrice BS, Lucas SJE, Akerman AP, et al.. Experimental Physiology, 2025.Read the paper ↗PubMed ↗Source 6 · Meta-analysisNon-acute effects of passive heating interventions on cardiometabolic risk and vascular health: systematic review and meta-analysis of randomized controlled trialsHamaya R, Joyama Y, Miyata T, et al.. American Journal of Preventive Cardiology, 2025.Read the paper ↗PubMed ↗

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Take your sauna after the workout. If you take blood pressure medicine, stand up slowly when you finish, since these drugs can make pressure drop further after bathing.Source 7 · ReviewHealth effects and risks of sauna bathingKukkonen-Harjula K, Kauppinen K. International Journal of Circumpolar Health, 2006.Read the paper ↗PubMed ↗

On Sauna MonthlyAn indoor sauna puts the heat down the hall

Heat · 03

79°C

average heat in the Finnish saunas behind the long-term data

The long-term sauna data come from hot, traditional rooms.

The Finnish men sat at about 79°C for 14 minutes a session.Source 1 · Cohort studyAssociation Between Sauna Bathing and Fatal Cardiovascular and All-Cause Mortality EventsLaukkanen T, Khan H, Zaccardi F, et al.. JAMA Internal Medicine, 2015.Read the paper ↗PubMed ↗ In a head-to-head study, a typical infrared session left core temperature unchanged, and a traditional sauna raised it 0.4°C.Source 8 · Crossover trialComparison of thermoregulatory, cardiovascular, and immune responses to different passive heat therapy modalitiesAtencio JK, Reed EL, Wiedenfeld Needham K, et al.. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2025.Read the paper ↗PubMed ↗

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If you're buying for health, choose a sauna that reaches about 80°C. An infrared cabin loads the body the same way only when it runs hotter and longer than its usual 45–60°C.Source 9 · Clinical trialFar‐infrared sauna exposure at 65°C elevates core temperatureJenkins EJ, Killick JA, Grimm SR, et al.. Experimental Physiology, 2026.Read the paper ↗PubMed ↗

On Sauna MonthlySauna Monthly weighs infrared against traditional

Heat · 04

61 kcal

extra burned in an hour of passive heat, against 556 for an hour of cycling

A sauna burns a few dozen calories, and the weight you lose is water.

Measured by calorimetry, an hour of passive heat burned 61 kcal more than rest, and an hour of moderate cycling burned 556 more.Source 10 · Crossover trialThe effect of passive heating on heat shock protein 70 and interleukin-6: A possible treatment tool for metabolic diseases?Faulkner SH, Jackson S, Fatania G, et al.. Temperature, 2017.Read the paper ↗PubMed ↗ In a trial that measured fat, a sauna after exercise added no fat loss beyond the exercise itself.Source 4 · Randomized trialEffects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trialLee E, Kolunsarka I, Kostensalo J, et al.. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2022.Read the paper ↗PubMed ↗

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Count the sauna as rest when you track calories, and weigh yourself before a session. If your watch logs a sauna as a workout, delete the entry.

On Sauna MonthlyA wearable shows the adaptation happening

Heat · 05

of a day's urine lead, carried by half a liter of sweat

Your kidneys and gut do the detox, and sweat carries traces.

Half a liter of sweat carries about 8% of the lead that a day's urine removes.Source 11 · Clinical trialLead in sweat and its relationship to salivary and urinary levels in normal healthy subjects1Omokhodion F, Crockford G. The Science of The Total Environment, 1991.Read the paper ↗PubMed ↗Source 12 · BookDietary Reference Intakes for Water, Potassium, Sodium, Chloride, and SulfateInstitute of Medicine. National Academies Press, 2005.Read the paper ↗ A 2019 review of sweat physiology calls sweat's role in clearing toxicants minor next to the kidneys and gut.Source 13 · ReviewPhysiology of sweat gland function: The roles of sweating and sweat composition in human healthBaker LB. Temperature, 2019.Read the paper ↗PubMed ↗

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Use the sauna for the heat, and drink water to replace what you sweat. If a clinic sells sweating as a way to clear metals, ask what it measured.

On Sauna MonthlySauna Monthly decodes infrared sauna marketing

Heat · 06

6 months

for sperm counts to recover after three months of regular saunas

Regular saunas lower sperm counts, and the drop reverses.

Two 15-minute sessions a week at 80–90°C for three months cut sperm count and motility in 10 men. Every measured change had reversed six months after they stopped.Source 14 · Clinical trialSeminal and molecular evidence that sauna exposure affects human spermatogenesisGarolla A, Torino M, Sartini B, et al.. Human Reproduction, 2013.Read the paper ↗PubMed ↗

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If you're trying to conceive, talk to your doctor about pausing saunas and hot baths for a few months.

30°HSperm count

These findings about cold hold up

Cold · 07

103 g

of quadriceps gained with ice baths after lifting, against 309 g without

Ice baths right after lifting slow your muscle gains.

Men who sat in 10°C water after every leg session for 12 weeks added 103 g of quadriceps muscle, against 309 g after light cycling.Source 15 · Randomized trialPost‐exercise cold water immersion attenuates acute anabolic signalling and long‐term adaptations in muscle to strength trainingRoberts LA, Raastad T, Markworth JF, et al.. The Journal of Physiology, 2015.Read the paper ↗PubMed ↗ Pooled trials agree on the direction, and cold after endurance sessions showed no such cost.Source 16 · Meta-analysisThe Effects of Regular Cold-Water Immersion Use on Training-Induced Changes in Strength and Endurance Performance: A Systematic Review with Meta-AnalysisMalta ES, Dutra YM, Broatch JR, et al.. Sports Medicine, 2021.Read the paper ↗PubMed ↗

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If you lift for size or strength, keep cold water away from the minutes after training. Plunge on rest days or after cardio.

22°HBlunted gains

On Sauna MonthlyTime your plunge around your training

Cold · 08

0.3

points less soreness on a 0–10 scale after an ice bath

Cold water after hard exercise eases soreness a little.

Across trials, ice baths after exercise cut soreness by about 0.3 points on a 0–10 scale, and water at 10–15°C for 10–15 minutes did best.Source 17 · Meta-analysisCan Water Temperature and Immersion Time Influence the Effect of Cold Water Immersion on Muscle Soreness? A Systematic Review and Meta-AnalysisMachado AF, Ferreira PH, Micheletti JK, et al.. Sports Medicine, 2016.Read the paper ↗PubMed ↗

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Save the ice bath for days when soreness is what's holding you back, like the day before a race or a match.

30°HFaster recovery

On Sauna Monthly · $1,749.99Ice Barrel 500

Cold · 09

5 min

in 13.6°C sea water lifted mood as much as 20 minutes did

A few minutes of cold water lifts mood right afterward.

Students with low mood felt about as much better after 5 minutes in 13.6°C sea water as after 20.Source 18 · Randomized trialImproved Mood Following Cold‐Water Immersion: A Comparison of Differing Exposure DurationsKelly JS, Davidson N, Delaney JP. Lifestyle Medicine, 2026.Read the paper ↗ None of the mood studies used a placebo, so expectation plays a part.

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Keep dips short if you're doing it for your mood. Five minutes did as much as twenty.

34°HBetter mood

On Sauna MonthlyThese cold plunge tubs are worth buying

Cold · 10

30 s

of cold at the end of a shower did as much as 90 seconds

A cold finish to your shower is a free way to try cold.

In a trial of 3,018 Dutch adults, ending a hot shower with 30 to 90 seconds of cold cut sick days off work by 29%, and 30 seconds did as much as 90. The number of days people felt ill didn't change significantly.Source 19 · Randomized trialThe Effect of Cold Showering on Health and Work: A Randomized Controlled TrialBuijze GA, Sierevelt IN, van der Heijden BCJM, et al.. PLOS ONE, 2016.Read the paper ↗PubMed ↗

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Finish your shower with 30 seconds of cold for a month and see whether you like it.

On Sauna MonthlyRun the Nordic hot and cold cycle at home

Cold · 11

2–3×

rise in noradrenaline after a short, very cold dip

A short, very cold dip sends noradrenaline up two- to threefold.

Twenty seconds in 0–2°C water raised noradrenaline two- to threefold after every swim for 12 weeks.Source 20 · Clinical trialEffects of long‐term whole‐body cold exposures on plasma concentrations of ACTH, beta‐endorphin, cortisol, catecholamines and cytokines in healthy femalesLeppäluoto J, Westerlund T, Huttunen P, et al.. Scandinavian Journal of Clinical and Laboratory Investigation, 2008.Read the paper ↗PubMed ↗ The famous 250% dopamine figure came from an hour in 14°C water, measured in the blood.Source 21 · Clinical trialHuman physiological responses to immersion into water of different temperaturesŠrámek P, Šimečková M, Janský L, et al.. European Journal of Applied Physiology, 2000.Read the paper ↗PubMed ↗

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Use a plunge as a wake-up if you like it, and judge it by how you feel in the hour afterward.

74°HDopamine

On Sauna MonthlyCold plunge tubs range from ice barrels to chillers

A few rules keep heat and cold safe

Safety · 12

1 min

for the gasp and fast breathing of cold shock to settle

The first minute in cold water is the dangerous part.

Men new to 10°C water breathed 47 times a minute in their first 30 seconds.Source 22 · Clinical trialPermanence of the habituation of the initial responses to cold-water immersion in humansTipton MJ, Mekjavic IB, Eglin CM. European Journal of Applied Physiology, 2000.Read the paper ↗PubMed ↗ In lab studies, holding the breath under cold water set off irregular heartbeats in 62% to 82% of submersions.Source 23 · Review‘Autonomic conflict’: a different way to die during cold water immersion?Shattock MJ, Tipton MJ. The Journal of Physiology, 2012.Read the paper ↗PubMed ↗

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Keep your face out of the water and breathe through the first minute. Never hold your breath under cold water, and have someone nearby.

18°HCold shock

Safety · 13

1 in 2

Finnish sauna deaths from 1990 to 2002 involved alcohol

Half the people who died in Finnish saunas had been drinking.

Forensic records show alcohol in half of Finnish sauna deaths from 1990 to 2002.Source 24 · Case seriesDeath in Sauna*Kenttämies A, Karkola K. Journal of Forensic Sciences, 2008.Read the paper ↗PubMed ↗ In a small experiment, sauna plus alcohol dropped systolic pressure from 136 to 113 mmHg, where the sauna alone left it at baseline.Source 25 · Clinical trialAlcohol and sauna bathing: effects on cardiac rhythm, blood pressure, and serum electrolyte and cortisol concentrationsRoine R, Luurila OJ, Suokas A, et al.. Journal of Internal Medicine, 1992.Read the paper ↗PubMed ↗

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Keep alcohol out of the sauna and skip it the morning after heavy drinking. Don't let anyone who has been drinking bathe alone.

Safety · 14

8 weeks

to wait after a heart attack before using a sauna

Heart patients and pregnant women should check with a doctor first.

People with stable heart disease tolerated sauna sessions in small studies, and Finnish experts advise staying out while chest pain is new or unstable or within eight weeks of a heart attack.Source 7 · ReviewHealth effects and risks of sauna bathingKukkonen-Harjula K, Kauppinen K. International Journal of Circumpolar Health, 2006.Read the paper ↗PubMed ↗ In pregnancy, the reassuring data cover up to 20 minutes at around 70°C.Source 26 · Systematic reviewHeat stress and fetal risk. Environmental limits for exercise and passive heat stress during pregnancy: a systematic review with best evidence synthesisRavanelli N, Casasola W, English T, et al.. British Journal of Sports Medicine, 2019.Read the paper ↗PubMed ↗

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If you have heart disease or you're pregnant, talk to your doctor or midwife before you start, and keep sessions shorter and cooler if you get the go-ahead.