Last updated: October 2026
Sauna benefits are real but often overstated. Large Finnish studies link regular sauna use with a lower risk of high blood pressure and fewer heart deaths, and many people find it deeply relaxing, but this shows an association, not proof. For most healthy adults, 10 to 15 minutes, two to four times a week, is a sensible routine.
Below: the evidence, how long and how often, workouts, sleep, skin, steam rooms, cold plunges and who should take care.
Sauna benefits: what the research says
The best-known study followed 2,315 middle-aged Finnish men for about 21 years. Those who used a sauna four to seven times a week had half the rate of sudden cardiac death of men who went once a week (5.0% vs 10.1%), and fewer deaths overall (30.8% vs 49.1%). Sessions of more than 19 minutes were linked with lower heart risk than sessions under 11 minutes. A later analysis of the same men found frequent users were about half as likely to develop high blood pressure.
The catch: these were observational studies, and people well enough to sit in a sauna most days may simply be healthier to begin with. A 2018 review of 40 studies found only 13 were randomised trials, and most had fewer than 40 people. Its verdict: regular sauna “has potential health benefits” but needs better research.
| Claimed benefit | What the evidence shows |
|---|---|
| Heart health and blood pressure | Strong associations in Finnish cohorts; not proof of cause |
| Relaxation | The main reason people go; few good trials measure it |
| Fewer colds | One small 1990 trial (50 people) found fewer colds, but not shorter or milder ones |
| Weight loss | Water weight only; it returns when you drink |
| “Detox” | No good evidence; reviewers call such claims scant and incomplete |
How long to stay in a sauna, and how often
Finnish saunas run at 80 to 100°C, and studies typically use sessions of 5 to 20 minutes. A simple routine for healthy adults:
- First few visits: 5 to 10 minutes on a lower bench, where it’s cooler.
- Once you’re used to it: 10 to 15 minutes, then cool down for 5 to 10 minutes. Repeat once or twice if you feel well.
- How often: two to four times a week is where most of the research sits.
- Leave straight away if you feel dizzy, sick, very thirsty or get a headache. These are NHS signs of heat exhaustion: cool down and drink.
Stand up slowly when you leave. Blood vessels widen in the heat, so a quick change in position can make you light-headed.
Sauna after a workout
A post-workout sauna feels good, but evidence for faster recovery is thin. In one study of just six male runners, about 30 minutes of sauna after training, roughly 13 times over three weeks, raised blood plasma volume by around 7% and improved endurance on a treadmill test. Interesting, not settled.
Drink water first, keep it short because you’re already warm, and skip it after a long session in hot weather. Our guide to muscle recovery covers what helps most (sleep, protein and rest days), and magnesium and cramps looks at cramping after heavy sweating.
Sauna for sleep and relaxation
Many people sleep well after a sauna, but few trials test it directly. The closest evidence is for warm baths and showers: a review of 17 studies found that 10 minutes or more of warm water (40 to 42.5°C), 1 to 2 hours before bed, helped people fall asleep faster, probably because core temperature drops afterwards. So finish an evening sauna 1 to 2 hours before bed. For more ways to wind down, see sleep hygiene habits, how to relieve stress and progressive muscle relaxation. A warm, cosy sauna evening also fits neatly into hygge.
Sauna benefits for skin and weight loss
Skin: a small German study found regular sauna users had better skin hydration and a more stable skin barrier than non-users. Encouraging, but exploratory. If your skin flushes easily, keep sessions short.
Weight loss: any drop on the scales is water. In a study of 674 young adults, two 10-minute sessions at 90°C led to an average loss of 0.37kg in women and 0.50kg in men, all from sweat. It comes straight back when you rehydrate, as you should.
Sauna vs steam room
A steam room feels cooler on the thermometer but can be harder work. In very humid air, sweat can’t evaporate, so it cools you less. In one study of young women, a humid sauna at 59°C raised core temperature and heart rate more than a dry sauna at 91°C.
| Type | Typical temperature | Humidity |
|---|---|---|
| Dry (Finnish) sauna | 80 to 100°C | 10 to 20%, briefly higher when water goes on the stones |
| Steam room | Lower | Very high |
| Infrared sauna | 45 to 60°C | Dry |
Neither is clearly better. Dry saunas are the most studied; pick the one you enjoy and keep steam room sessions short.
Sauna and cold plunge
A 2026 Bangor University study found that adding a 90-second dip in 20°C water to the cooling break between two 15-minute sauna rounds left people with a lower core temperature and heart rate by the end of the second round, and they found the heat easier to tolerate.
Start with a cool shower, and ask your doctor before cold plunging if you have a heart condition. Our guide to cold showers explains how to build up, and the vagus nerve guide covers the cold water “diving reflex”.
Who should avoid a sauna or take care
Sauna is well tolerated by most healthy people. Take care if:
- You’re pregnant: the charity Tommy’s says there’s no evidence that occasional sauna use causes miscarriage, but a significant rise in core temperature could be harmful, particularly in the first 12 weeks. Talk to your midwife first.
- You have a heart condition: the British Heart Foundation explains that heat makes the heart work harder and can drop blood pressure. With angina, heart failure or a fluid limit, ask your GP or heart team first.
- You have low blood pressure or take blood pressure medicines: you may feel dizzy standing up afterwards.
- You’ve been drinking: deaths in saunas are rare (under 2 per 100,000 people a year in Finland), but half of those who died had been drinking. Don’t mix the two. See cutting down on alcohol.
- You’re unwell or have a high temperature: wait until you’re better.
- You’re a man trying for a baby: Tommy’s advises avoiding saunas, as sperm need to stay cool.
Staying hydrated: water and electrolytes
Drink a glass of water before you go in and one or two afterwards. Dark yellow pee, a headache or feeling light-headed are NHS signs of dehydration. Plain water is enough after a normal session; after very heavy sweating, the NHS says an isotonic drink or rehydration powder helps replace lost salt. Our electrolytes guide explains when they’re worth it.
Magnesium contributes to electrolyte balance and to normal muscle function. Our Magnesium Glycinate Sleep Complex is a caffeine-free evening drink with magnesium bisglycinate and citrate. It isn’t a replacement for water. For more seasonal ideas, see winter wellness.
FAQs
How long should you stay in a sauna?
Start with 5 to 10 minutes. Once you’re used to it, 10 to 15 minutes per round with a cooling break is typical. Leave at once if you feel dizzy or unwell.
Is it OK to use a sauna every day?
For most healthy adults, yes, if you feel well and stay hydrated. The Finnish studies linked four to seven sessions a week with the lowest heart risk, but that is an association, not proof.
Does a sauna help you lose weight?
Not fat. In one study, two 10-minute sessions removed about 0.4 to 0.5kg of water, which returns when you drink.
Is a sauna good when you have a cold?
One small trial found regular sauna users caught fewer colds, but not milder ones. If you’re already ill or have a high temperature, skip it and rest. See how to sleep with a cold.
Should you use a sauna before or after a workout?
After is more common, once you’ve had a drink. Using one before means starting your session already hot and sweaty.
Sources
- Laukkanen T, et al. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med, 2015.
- Zaccardi F, et al. Sauna bathing and incident hypertension: a prospective cohort study. Am J Hypertens, 2017.
- Hussain J, Cohen M. Clinical effects of regular dry sauna bathing: a systematic review. Evid Based Complement Alternat Med, 2018.
- Scoon GS, et al. Effect of post-exercise sauna bathing on the endurance performance of competitive male runners. J Sci Med Sport, 2007.
- Haghayegh S, et al. Before-bedtime passive body heating by warm shower or bath to improve sleep. Sleep Med Rev, 2019.
- Podstawski R, et al. Sauna-induced body mass loss in young sedentary women and men. ScientificWorldJournal, 2014.
- Kowatzki D, et al. Effect of regular sauna on epidermal barrier function and stratum corneum water-holding capacity. Dermatology, 2008.
- Pilch W, et al. Physiological indicators and thermal stress in a dry and wet sauna in young healthy women. Med Pr, 2019.
- Owen TF, et al. Thermal and cardiovascular responses to sauna are attenuated by adding cold water immersion to cooling breaks. Exp Physiol, 2026.
- Ernst E, et al. Regular sauna bathing and the incidence of common colds. Ann Med, 1990.
- Kenttämies A, Karkola K. Death in sauna. J Forensic Sci, 2008.
- Kukkonen-Harjula K, Kauppinen K. Health effects and risks of sauna bathing. Int J Circumpolar Health, 2006.
- Tommy’s. What causes a miscarriage? and How to improve male fertility.
- British Heart Foundation. Hot weather advice for heart patients.
- NHS. Heat exhaustion and heatstroke, Dehydration and Low blood pressure.
This guide is general information, not medical advice. If you have a health condition, are pregnant or take medicines, check with your GP before using a sauna. Evopure makes the Magnesium Glycinate Sleep Complex.
