15 Items You Should Always Leave Outside the Sauna

Ever tossed your phone or towel into the sauna, thinking it’s harmless? Many make this mistake, only to end up with damaged gadgets, sweaty fabrics, or even a safety hazard. 

It’s frustrating and avoidable. In this post, we reveal 15 essential items you should always leave outside the sauna to keep your belongings safe and your experience stress-free.

• Protect Your Electronics: Leave phones, headphones, and other gadgets outside to avoid heat and moisture damage.
  
  

• Safeguard Valuables: Remove watches, jewelry, and personal documents to prevent burns, corrosion, or warping.
  
  

• Prioritize Eye and Skin Safety: Skip contact lenses, makeup, skincare products, lotions, oils, and perfumes to avoid irritation or reduced effectiveness.
  
  

• Keep the Sauna Hygienic: Leave shoes, street clothes, and food outside to maintain cleanliness and prevent bacterial growth.
  
  

• Avoid Health Risks: Stay away from alcohol, heavy towels, and workout equipment to prevent dehydration, overheating, and accidents.

Bringing smartphones or other electronic devices into a sauna is a recipe for disaster. Dry saunas can reach temperatures of 80–90°C (176–194°F), which is far beyond what most electronics are built to handle, many phones automatically shut down around 30–35°C (86–95°F) to avoid overheating. 

Extended exposure to such heat can shorten battery life, warp internal components, or even render a device completely useless. 

Traditional and infrared saunas also produce high humidity, which can seep into your gadgets and cause short circuits, corrosion, or permanent damage. 

Research indicates that over 50% of electronic failures are linked to high temperatures, with moisture adding an extra layer of risk. 

Even brief stints in the sauna can compromise performance, reduce lifespan, and trigger unexpected malfunctions. 

Experts strongly recommend keeping electronics in a cool, dry area instead. By leaving your devices outside, you protect them from extreme heat and moisture, ensuring they continue to work reliably whenever you need them.

When it comes to saunas, it’s wise to leave your watches and jewelry behind. High heat and humidity can turn metals like silver, gold, copper, and even stainless steel into dangerous heat conductors, heating up faster than your skin can detect and potentially causing burns as experts warn. 

Beyond personal safety, prolonged exposure to heat and steam can also damage your treasured pieces. 

Moisture combined with sauna temperatures may weaken jewelry settings, cause discoloration, rust, or tarnish, and even compromise a watch’s water resistance by affecting gaskets and seals according to manufacturers’ guidelines. 

Even water-resistant watches can suffer when exposed to hot steam or baths, as heat may expand sealing components and allow moisture inside industry advice. 

To protect both your valuables and your skin, it’s best to remove all jewelry and watches before stepping into a sauna, hot shower, or any high-humidity, high-temperature environment as studies and experts suggest.

As noted by All About Vision, it’s best to remove your contact lenses before entering a sauna. 

The extreme heat and steam can dry out lenses, causing discomfort, blurry vision, and even altering their shape and fit. 

This can create tiny scratches on your cornea and increase the risk of eye irritation or infection. 

Saunas may also expose lenses to microorganisms like bacteria, fungi, and acanthamoeba, which can result in serious eye infections if contamination occurs. 

While the steam from a shower is usually gentle, the intense conditions of a sauna make wearing contacts risky. 

Eye care specialists recommend taking out your lenses in high-heat environments to protect your eyes and avoid long-term damage. 

All About Vision also emphasizes that when spending time outdoors, lenses with UV protection and polarized sunglasses are essential, regardless of temperature. 

Following these precautions keeps your eyes comfortable, healthy, and safe, so you can enjoy the sauna without any worry.

Leaving your makeup and skincare products in a sauna is a recipe for disaster. According to experts, the intense heat and humidity can chemically destabilize your products, causing oils, waxes, and water to separate, which can render them ineffective. 

Research shows that extreme temperatures can reduce the potency of key ingredients, including sun protection agents, meaning your favorite creams and serums might not work as intended. 

Even everyday situations, like a steamy bathroom, can create similar problems. Dermatologists and cosmetic chemists warn that humidity can allow moisture into containers, increasing the risk of contamination and breaking down active ingredients. 

To keep your products safe, store them in cooler, more stable areas, such as a bedroom dresser or vanity. 

By keeping your makeup and skincare away from heat and moisture, you preserve their effectiveness and extend their shelf life. 

Your beauty routine will thank you, and you won’t waste products that are meant to protect and nourish your skin.

When stepping into a sauna, it’s best to leave shoes and street clothing behind. Shoes can track in dirt and germs from outside, which not only dirties the sauna but also affects hygiene for everyone using it. 

Placing shoes directly on the bench is especially frowned upon, as it’s seen as both unhygienic and impolite. 

Likewise, while light clothing is sometimes acceptable, health and spa guidelines suggest wearing breathable, loose-fitting garments rather than tight sweaters or snug undergarments. 

Such clothing lets your skin breathe and helps your body maintain a comfortable temperature. 

Experts also note that wearing clothes can reduce the transfer of germs, bacteria, or bodily fluids onto sauna benches, keeping the environment cleaner and safer. 

By following these simple habits, going barefoot and choosing suitable attire, you create a more enjoyable, hygienic experience for yourself and others, all while showing respect for this shared space.

Leaving plastic water bottles in hot environments, like a sauna, can be risky. Research cited by PubMed shows that heat speeds up the release of chemicals such as BPA, phthalates, antimony, and microplastics into the water. 

PET bottles, which are commonly used for single-use water, can also release formaldehyde, acetaldehyde, and trace metals when exposed to high temperatures. 

While some studies found that these chemicals didn’t immediately cause harmful effects, long-term exposure has been linked to hormone imbalances, metabolic issues, gastrointestinal irritation, and even cancer. 

Exposure to sunlight and UV rays can further accelerate this chemical leaching. To protect your health, experts recommend avoiding plastic bottles in hot conditions and choosing safer alternatives like glass, stainless steel, or food-grade silicone. 

These options are durable, non-reactive, and suitable for both hot and cold beverages, letting you stay hydrated without worrying about potential chemical exposure.

Bringing food into a sauna is never a good idea. The high heat and humidity can quickly ruin both the safety and quality of your snacks. 

Eating before a sauna can also cause problems, your digestive system slows down during the session, which may lead to nausea, headaches, or even food poisoning. 

The intense temperatures create an ideal environment for bacteria. As reported in the Journal of Bacteriology and Virology, dry saunas can contain thermophilic and thermoduric bacteria that survive and even thrive at 50–60℃. 

Humidity adds another risk, encouraging mold and bacterial growth that spoils food and reduces its nutritional value. 

Packaging is also vulnerable, heat and moisture can weaken cans or paper wrapping, potentially contaminating the contents. 

Overall, storing or eating food in a sauna compromises both health and taste. It’s much safer to enjoy your meals before or after your session rather than risking them inside the sauna.

Bringing alcohol into a sauna is a dangerous choice and should be avoided. Medical News Today explains that alcohol disrupts your body’s ability to manage temperature, worsens dehydration, and causes blood vessels to widen, which can lead to sharp drops in blood pressure. 

In the intense heat of a sauna, these effects are amplified: the heart must work harder to pump blood, while alcohol hampers your body’s ability to cool itself and recognize overheating. 

Research highlighted on PubMed shows that this combination can trigger dizziness, fainting, or even collapse, increasing the risk of burns, falls, or other accidents. 

Studies from Finland indicate that alcohol is linked to 20–25 sauna-related deaths each year, with dangers including heat stroke, arrhythmias, and sudden cardiac events. Even minor mishaps like sprains or burns are more likely when drinking in the sauna. To enjoy a safe and relaxing session, it’s best to leave alcoholic beverages outside.

It’s tempting to bring a book or magazine into the sauna for some relaxing reading, but paper items are extremely sensitive to heat and moisture. 

High temperatures can warp pages, loosen bindings, and cause adhesives to soften or bleed, while humidity can make pages swell, stick together, or even develop mold. 

Over time, repeated exposure can lead to yellowing, brittleness, tears, and chemical deterioration, shortening the life of your favorite reads. 

Studies featured in Building and Environment highlight that even moderate heat and poor climate control in archives can dramatically affect the longevity of paper collections, underlining the cumulative risks. 

Moisture can also damage metal clasps, paper clips, and other fasteners, adding to the overall deterioration. 

While protective covers may offer some limited defense, they cannot fully prevent these effects. 

To truly preserve your books and magazines, it’s much safer to enjoy reading outside the sauna, keeping both your papers and your relaxation worry-free.

High heat and humidity can take a serious toll on your headphones and earbuds. As SONY points out, extreme heat can melt plastic or rubber parts, while very cold temperatures can make them brittle and prone to cracking. 

Moisture is another hidden danger, it can cause corrosion or even short circuits over time. Studies have shown that repeated exposure to small amounts of steam or condensation can damage the internal components of earbuds. 

Even if your headphones are marketed as waterproof or water-resistant, SONY and other manufacturers strongly warn against using them in saunas or environments with extreme temperatures. 

Electronics are built to function within certain temperature ranges, and saunas, with their 70-90°C heat and high humidity, far exceed these safe limits. 

To protect your devices, keep them away from direct sunlight, radiators, ovens, freezers, or humidifiers. 

If they do get wet, dry them thoroughly before use. Taking these precautions can help your headphones last longer and avoid costly damage.

When heading into the sauna, it’s best to skip lotions, oils, and perfumes. These products can clog your pores, trapping sweat and toxins and limiting the detoxifying benefits of your session. 

On top of that, some lotions or oils may react to the high heat, causing skin irritation or discomfort. 

Essential oils, while lovely in scent, carry an extra risk, they’re flammable, and applying them near a hot sauna heater could even start a fire. 

Healthline notes that experts also recommend exercising caution in saunas if you have certain health conditions, including heart disease, asthma, epilepsy, abnormal blood pressure, or if you are pregnant, under the influence of alcohol, or taking certain medications. 

Simply leaving lotions, oils, and perfumes outside allows your body to sweat naturally, keeping your sauna experience safe, soothing, and truly effective.

Heat can be surprisingly harmful to your eyeglasses and sunglasses, which is why optometrists strongly recommend keeping them away from hot environments like saunas. 

High temperatures can warp frames, soften plastic, or even melt the glue holding parts together, leaving your glasses loose or broken. 

Lens coatings, such as anti-reflective layers, may also be damaged by heat, causing visual distortions or reducing their effectiveness. 

In extreme cases, plastic lenses might crack or warp, and polarized films can be ruined. Research shows that exposure to very high heat, from car dashboards, stovetops, or open flames, can weaken frames and lenses. 

Common signs of heat-related damage include warped frames, crazing (a fine web of cracks on the lenses), and diminished coating performance. 

Protecting your eyewear from heat not only extends its lifespan but also keeps your vision clear and comfortable. 

So, before stepping into a sauna, it’s best to leave your glasses safely outside to avoid unnecessary damage.

Bringing heavy towels or blankets into a sauna might feel comforting, but heavy towels and blankets can actually make your session uncomfortable and even unsafe. 

These thick fabrics act as insulators, trapping heat and moisture against your skin, which disrupts your body’s natural cooling process. 

Rather than making you warmer, they can lead to overheating and reduce proper airflow, making it harder for sweat to evaporate and the skin to breathe. 

Health specialists and sauna experts often highlight that heavy or tight clothing restricts movement, limits skin respiration, and interferes with natural thermoregulation. 

In hot environments like saunas, lightweight and loose-fitting options, such as airy cotton garments, a simple towel, or even minimal clothing, allow air to flow freely, helping your body cool naturally while staying comfortable. 

Choosing lighter fabrics ensures a safer and more relaxing sauna experience, letting you fully enjoy the benefits of heat and sweating without the risks tied to [heavy towels and blankets.

Bringing workout equipment or metal items into a sauna can be risky, potentially harming both your skin and your gear. 

As noted, metal objects, like watches or jewelry, heat up quickly and can burn, so it’s safest to remove them before stepping inside. 

Gym equipment and weights are also affected, as high heat and humidity can cause them to wear out faster, shortening their lifespan. 

Fitness gear made of rubber, plastic, or leather is particularly sensitive: rubber may warp or lose elasticity, plastics can melt or release toxic fumes, and leather can dry, crack, or lose its shape. 

Even glasses can fog up, while contact lenses might feel uncomfortable or dry out. To enjoy a safe sauna session, leave all fitness gear and electronics in the locker room. 

Stick to minimal clothing, such as a swimsuit or breathable cotton, and bring a towel to sit on. Doing so protects your belongings and ensures the sauna remains a safe, relaxing retreat.

Bringing electronics or important documents into a sauna is never a smart move. The high heat, usually between 150°F and 195°F (65°C to 90°C), can easily cause your phone or other devices to overheat, damaging batteries, processors, and screens according to experts. 

Humidity adds another layer of risk: moisture can infiltrate electronics, corroding internal components, while metal jewelry may become uncomfortably hot [as noted by public sauna guidelines. 

Even short exposure can result in condensation, short-circuits, or permanent screen damage according to safety recommendations. 

To protect your belongings, public saunas advise leaving all valuables in a secure locker outside the sauna. 

Many facilities offer keyed, electronic, or RFID lockers, often supervised by staff, and rules typically forbid bringing personal electronics or important documents inside as suggested by spa policies. 

For added caution, leave non-essential items at home, use separate lockers for different valuables, or carry a waterproof pouch for small necessities. 

While thermal phone cases exist, the safest choice remains simple: relax and enjoy the sauna without risking your valuables [as recommended by professionals.

This article has explored the risks of bringing electronics, jewelry, contact lenses, makeup, clothing, and other personal items into a sauna, highlighting how heat and humidity can damage devices, materials, and even your health. 

These findings underscore the importance of leaving valuables outside, allowing the sauna to remain a safe, hygienic, and effective space for relaxation. 

Future exploration could examine innovative storage solutions or materials designed to withstand extreme sauna conditions, further protecting both belongings and users.