While saunas can provide a welcomed source of relaxation and warmth, there can be too much of a good thing: If you stay in a sauna too long, you risk dizziness, dehydration, low blood pressure and nausea.

With the right guidelines, though, you can learn how long you can safely stay in a sauna and enjoy a safer, more relaxing experience.

In general, sauna users should stick to these time frames:

  • For beginners, limit sauna sessions to five to 10 minutes.
  • For experienced users, limit sauna sessions to 10 to 20 minutes.

Here, we’ll go in-depth about sauna safety and how you can avoid staying in for too long.

Why You Shouldn’t Use a Sauna for Too Long

While saunas certainly provide a variety of benefits (check out our previous blog post to learn more about the benefits of saunas), they can also cause discomfort if used for extended periods of time.

If you overdo your sauna session, you may start to experience:

  • Dehydration: Sauna use triggers extreme sweating. According to a 2018 article in Harvard Health Publishing, “Sauna Health Benefits: Are saunas healthy or harmful?” the average person loses an entire pint of sweat during a brief sauna. All that sweating can cause dehydration, which can lead to headache, fatigue and dizziness.
  • Dizziness and nausea: When your body temperature rapidly rises, as it can after stepping into a hot sauna, you may become overheated. As a result, you may feel dizzy and nauseous. If you continue to stay in the sauna, you may even get heat stroke, which qualifies as a medical emergency and can cause serious damage to your body.
  • Low blood pressure: When exposed to the high heat of the sauna, your body will automatically start pumping more blood toward your skin’s surface, where it will become cooled when your sweat evaporates before returning to your core. In the extreme heat of a sauna, this mechanism can result in low blood pressure in your brain and organs, which may make you feel light-headed, nauseous and fatigued, and can result in blurred vision or even loss of consciousness.

Keep in mind that certain groups of people are more vulnerable to those side effects than others. For example:

  • According to a 1987 article published in the Journal of the National Medical Assocation, “Dehydration in the Elderly: A Short Review,” elderly people are prone to age-related changes in total body water, reduced thirst perception, reduced kidney function and other factors which create an increased risk for dehydration.
  • According to Mayo Clinic, people with diabetes, kidney disease or illnesses like the cold and flu are especially prone to dehydration.
  • According to the Centers for Disease Control and Prevention (CDC), older adults are more prone than younger adults to heat stress. This is because older people don’t adjust as quickly as young people to sudden changes in temperature, are more likely to have a medical condition that affects temperature regulation and are more likely to take medication that affects body temperature and perspiration.

How to Use a Sauna Safely

As we mentioned above, beginners should use caution and limit their sauna sessions to no more than five to 10 minutes, even if they feel fine.

Intermediate and experienced users can increase the length of their sauna sessions by five minutes increments but should refrain from staying in a sauna for more than 20 to 30 minutes total.

Of course, should you start to feel dizzy, nauseous or fatigued during your session, or if you start to experience blurred vision or a headache, step out of the sauna immediately and find a cool place to sit down until you feel normal again.

To ensure that you stay safe while using your sauna, follow these safety tips:

  • Stay hydrated: Drink a glass of cool water before entering the sauna, and drink another one to four glasses after you exit.
  • Turn down the heat: If you’re a beginner, or if you start to feel ill while using your sauna, turn down the heat to its lowest setting before starting another session.
  • Avoid alcohol: Avoid drinking alcohol either before or directly after your sauna session, as this can cause additional dehydration.
  • Cool down slowly: If you plunge into a cold shower or bath immediately after you exit (or jump into a freezing body of water or snow as is the tradition in Finland), you’ll place a significant amount of stress on your cardiovascular system. Instead, cool down with a glass of cool water and a cool (but not cold) shower.
  • Dress properly: While a swimsuit may seem like a logical choice for sauna attire, their waterproof fabrics can act as a trap for sweat and heat, raising your temperature even more. Opt for loose, breathable clothing instead (or forgo clothing altogether).
  • Don’t wear jewelry: Metal jewelry can quickly heat up in a sauna and may cause burns if not quickly removed.
  • Be aware of medical conditions: If you have any medical condition such as low (or high) blood pressure, cardiovascular diseases, diabetes, brain conditions or anything similar, as well as any surgical implants, consult with your doctor before using a sauna.

Remember, sauna sessions are not a competition. By taking these simple precautions, you can reduce your risk of adverse side effects and enjoy a safe, relaxing and pleasant sauna experience.