Is sauna therapy particularly useful?

October 3, 2009 4:24 PM

Are the benefits of sauna therapy real? Some family members of mine talk about saunas being useful for "getting out heavy metals." Supposedly, the body sweats them out.

I've not found any valid research to this, however. I've seen some studies suggesting potential other effects, however.

posted by mdpatrick to science & nature (11 answers total)

This was recently addressed at the Straight Dope.
posted by El_Marto at 4:30 PM on October 3, 2009 [3 favorites]

From what I was told by one professor who does cancer research -- about fifty years ago they found that heating the entire body up to above a certain temperature would indeed kill every cancerous cell.

Unfortunately, the death rate from heating the human body up above that temperature and the death rate from cancer was around the same.

He said that today, people are looking at ways to cool the brain while heating the rest of the body.
posted by Comrade_robot at 4:40 PM on October 3, 2009 [4 favorites]

[removed wall-o-text links to pubmed - AskMe should be for questions, not blog posts. sorry.]
posted by jessamyn at 4:46 PM on October 3, 2009

I'm particularly interested in the excretion aspect, which he kind of addressed, but not very well. One study suggesting PCB excretion MIGHT have been enhanced? I want some more firm data! Something like that could be legitimately useful.
posted by mdpatrick at 4:47 PM on October 3, 2009

No hard data, but the few times I've heard people talk about excreting toxins, it's usually as orangey/yellow sweat. I remembered them also mentioning that part of the "cleanse" is taking a lot of vitamin B and I wonder if it's just the excess vitamin coming out.
posted by bonobothegreat at 5:17 PM on October 3, 2009 [1 favorite]

The funny thing is, bonobothegreat, it seems like a relatively easy test to perform. Simply collect their sweat and check it's content. I'm really surprised that it's been so difficult to address this question. (Which is largely in part why I posted this -- I figure someone must have found some hard data I've just so far missed)
posted by mdpatrick at 5:23 PM on October 3, 2009 [1 favorite]

I've not found any valid research to this, however.

Because there isn't any. Detoxing heavy metals is a scam. For the rare occasions when someone has heavy metal toxicity, you remove the toxins through chelation, usually with dimercaptosuccinic acid (although some metals require a different agent).

Sitting in a sauna may have beneficial effects, I don't really know. But detoxing from heavy metals isn't one of them.
posted by Justinian at 5:46 PM on October 3, 2009 [3 favorites]

Isn't that why we go to the bathroom to excrete the excess toxins from our system?
Seems they are just, well, p**ing out their pores to put it crudely.
posted by Frugalforlife at 5:59 PM on October 3, 2009

The main ways your body dumps toxins it can't detoxify is in urine and feces. But in both cases there's heavy processing involved, respectively in the kidneys and liver, and not every toxin will make it through the filtration.

Some heavy metals are like that. The liver stores them instead of excreting them (in bile) because it doesn't have any chemical way to get hold of them and process them. What chelation does is to attach a biological marker to atoms of heavy metals which the liver can, and does, grab and excrete.

The fluid in sweat comes from blood plasma. But unlike the kidneys, which are extremely sophisticated and very selective about what they keep and what they get rid of, sweat glands are not very sophisticated. They just grab fluid plus whatever is dissolved in the fluid and dump it out on the surface of the skin.

That's why you lose a lot of salt in sweat, but won't lose anything like as much in your urine. Retaining salt when necessary is one of the things the kidneys are really good at. (They're also good at getting rid of it when you have too much.)

I think that if there are heavy metals in your blood plasma they'd also be dumped out in the sweat. But heavy metals don't circulate in the blood in very high quantities because the liver and certain other tissues tend to store them. And sweat glands don't have any ability to concentrate trace elements from the blood plasma.

And in any case, most people aren't carrying a toxic load of heavy metals. We aren't harmed (much, if a tall) by small quantities, precisely because the liver (and bones, and body fat etc.) do grab and store what comes by. In the case of things like lead and mercury, they only really become seriously toxic once the total load in the body exceeds the capacity of the liver (and bones etc.) to isolate and store them. (These things are a matter of degree, of course; it's not a digital switch.)

So I think this idea as proposed is mostly baloney. But IANAD.

(Another way the body gets rid of certain heavy metals is in hair and fingernails. One of the standard medical tests for non-fatal arsenic poisoning is to test the hair.)
posted by Chocolate Pickle at 7:13 PM on October 3, 2009 [6 favorites]

It will clear your sinuses for a few hours, and the shower afterwards is great.
posted by Burhanistan at 10:53 PM on October 3, 2009 [2 favorites]

Makes you drink lots and lots of water, and makes exfoliating crocodile skin a breeze in the shower afterwards. Obviously I live in an excruciatingly dry climate.

Also, you get to sit naked (or mostly naked) in a warm steamy room and it's non-sexual and socially acceptable.
posted by variella at 9:23 AM on October 4, 2009