Quick answer
- An infrared sauna gets you sweating hard, and studies have found trace metals and BPA in sweat.
- Reviews suggest sweat plays a supporting role. Your liver and kidneys still do most of the clearing.
- A session also works your circulation and leaves you calm, and a cold plunge adds a jolt of alertness.
- Sweat is mostly water and salt, so drink before and after, and add something salty after a long session.
In this article · 7 sections
"Infrared sauna detox" is one of the most searched phrases in wellness, and it deserves an answer built on research, not hype. Here's the short version: an infrared sauna gets you sweating, often a lot, and scientists have measured trace metals and everyday chemicals in sweat. Sweat isn't your body's main exit for waste, though. Your liver and kidneys handle most of that. Think of the sauna as a supporting act, and a very enjoyable one.
Here's what the studies found, what a sauna and cold plunge session adds, and how to hydrate so you walk out feeling great.
What researchers have found in sweat
Sweat is mostly water and salt, and its main job is cooling you down (Temperature, 2019). It carries more than that, though:
- Metals. A systematic review of 24 studies found arsenic, cadmium, lead and mercury in sweat. In people with higher exposure, sweat levels often exceeded blood or urine levels, and for some metals the daily amount lost through the skin could match or beat the amount lost in urine. The authors concluded that sweating deserves consideration and called for properly sized trials (Journal of Environmental and Public Health, 2012).
- BPA. In a study of 20 people, researchers found BPA, a chemical used in some plastics, in the sweat of 16, including some whose blood and urine showed none (Journal of Environmental and Public Health, 2012).
- Workout sweat versus sauna sweat. In a small study of 12 students, sweat from treadmill running held more nickel, lead, copper and arsenic than sweat from sitting in a sauna cabinet, while mercury levels were similar (International Journal of Environmental Research and Public Health, 2022). Training plus a sauna is a natural pairing.
Where sweat fits next to your liver and kidneys
The 2019 review that describes sweat in such detail is also clear about its limits. Compared with your kidneys and digestive tract, sweating plays a minor role in clearing waste, and some studies suggesting a bigger role may reflect how the sweat was collected (Temperature, 2019).
So here's the honest picture. Your liver and kidneys do the heavy lifting every day, sauna or no sauna. A good sweat is one more way out, not a replacement for either. If you're worried about something specific you've been exposed to, talk to your doctor: testing and treatment are medical questions.
What a sauna session does for you
The detox debate misses what people actually feel. A sauna session works your body, then lets it settle.
- Your heart gets moving. In 19 adults, a 25-minute sauna raised heart rate and blood pressure about as much as moderate exercise, and blood pressure fell below its starting level afterward (Complementary Therapies in Medicine, 2019).
- Then you calm down. In 93 adults, heart rate climbed during a 30-minute sauna and settled below its starting level during a 30-minute cool-down, with heart rate variability shifting toward rest (Complementary Therapies in Medicine, 2019).
- It's quiet. No screens, no small talk, no shared bench. In a private suite, the room is yours.
And the cold plunge?
No study shows a cold plunge flushes toxins, and we won't pretend one does. What the cold does well is wake you up. In 33 adults new to cold water, a 5-minute dip at 68°F left people feeling more active, alert and attentive, and less nervous (Biology, 2023). Our plunges are kept at 45 to 49°F, much colder than that study, so short dips go a long way.
Step out, towel off and head back to the heat. That back-and-forth is contrast therapy, and it's what our suites are built for. Our infrared sauna page shows the setup.
How to hydrate around a sauna session
Since sweat is mostly water and salt, this is the part of detox advice that really matters.
- Before: drink a glass or two of water in the couple of hours before you arrive. No need to chug a bottle at the door.
- During: bring a water bottle into the suite and sip between rounds.
- After: drink again, and after a long session have something salty too. An electrolyte drink works, and so do water and a snack.
- Skip alcohol before a session and right after. Heat and alcohol are a bad mix.
- Check in later. Still thirsty a few hours on? Keep drinking.
If you feel dizzy, light-headed or queasy in the heat, get out, sit somewhere cooler and drink some water. Feeling headachy or wiped out afterward is a cue to drink more, add salt and go shorter next time. If it keeps happening, check with your doctor.
Check with your doctor first if...
Heat and cold both ask a lot of your body. Talk to your doctor before you book if you're pregnant, have a heart condition or high blood pressure, take medication that affects your heart rate, blood pressure or how you handle heat, or have any other medical concern. Every guest signs our liability waiver before a first session, and our safety guide covers the basics.
So, does an infrared sauna help you detox?
It helps you sweat, and research shows sweat carries small amounts of metals and chemicals out with it. That part is real. It isn't a cleanse, and your liver and kidneys stay in charge. Come for the heat, the cold and the quiet, and let your body do what it already does well. A first visit is the easiest way to start: book 55 minutes at our San Diego or Temecula studio and try two or three easy rounds.
Questions people ask.
Does an infrared sauna detox your body?
It gets you sweating, and studies have found trace metals and BPA in sweat. Reviews suggest sweat plays a small role next to your liver and kidneys, so think of the sauna as a supporting act, not a cleanse.
Does sweating remove heavy metals?
A 2012 systematic review found arsenic, cadmium, lead and mercury in sweat, sometimes at higher levels than in blood or urine. How much that lowers your body's total load isn't settled. If you're worried about exposure, see your doctor.
Is sauna sweat different from workout sweat?
In one small 2022 study, sweat from running held more of several metals than sweat from sitting in a sauna. Plenty of people do both: train first, then sauna.
Does a cold plunge flush toxins?
There's no research showing that, and we don't claim it. Studies do suggest a short cold dip can leave you feeling more alert and less nervous.
How much water should I drink after a sauna session?
There's no single right amount. Sip between rounds, drink a glass or two afterward, and keep drinking if you're still thirsty later. After a long sweat, add something salty.
Is a sauna safe if I take medication?
Ask your doctor first. Some medications change how your body handles heat or affect your heart rate and blood pressure, and your doctor knows your situation.
Sources
- Baker LB. Physiology of sweat gland function: the roles of sweating and sweat composition in human health. Temperature, 2019.
- Sears ME, Kerr KJ, Bray RI. Arsenic, cadmium, lead, and mercury in sweat: a systematic review. Journal of Environmental and Public Health, 2012.
- Genuis SJ, et al. Human excretion of bisphenol A: blood, urine, and sweat (BUS) study. Journal of Environmental and Public Health, 2012.
- Kuan WH, Chen YL, Liu CL. Excretion of Ni, Pb, Cu, As, and Hg in sweat under two sweating conditions. International Journal of Environmental Research and Public Health, 2022.
- Ketelhut S, Ketelhut RG. The blood pressure and heart rate during sauna bath correspond to cardiac responses during submaximal dynamic exercise. Complementary Therapies in Medicine, 2019.
- Laukkanen T, et al. Recovery from sauna bathing favorably modulates cardiac autonomic nervous system. Complementary Therapies in Medicine, 2019.
- Yankouskaya A, et al. Short-term head-out whole-body cold-water immersion facilitates positive affect and increases interaction between large-scale brain networks. Biology, 2023.
