Now for Some Steaming Sauna Science

15038090674_24d0663e91_o

Wet sauna a.k.a. steam bath

Previously in December 2014, Spanking FIT took an in-depth look at the heated debate regarding alleged dry sauna therapeutic benefits and hazards. However, as all serious visitors to the health spa know,  generally there is an option; namely, the wet variety of sauna or the so-called “steam bath”. A steam bath is created when a steam bath generator boils water into steam which is then injected into a closed space or room. The room used for this purpose has to be virtually airtight to allow the humidity to build up to nearly one hundred percent. However, it is important that steam rooms operate at lower temperatures (generally around 110° F., in contrast to the 180° F. for most saunas) to avoid user discomfort, and to prevent hot humid air from causing burns. Following an intense workout, my personal preference is for the dry sauna, but I know that many others do find the “wet feel” more enjoyable, and prefer a steam bath after workout. Once again, Spanking FIT scientifically examines the issue of whether or not the steam bath has therapeutic value, and also asks if there is evidence that favors one over the other (i.e. steam bath versus sauna). But, first, we present a brief steam bath history:

Steam bath history

From our research, it was clear that the history of steam bath usage stretches way back to the bronze age (around 3,000 B.C.) as evidenced by the ancient ruins found in the Indus Valley (what is currently India and Pakistan). Later, in the western world (around 1,000 B.C.), the Spartans developed primitive vapor baths heated by hot rock method. The steam was generated by pouring water over the rocks. Steam bath usage reached a grandiose apex with the construction of the Baths of Diocletion by the Romans around 300 C.E. The ancient Roman thermae as it was called, included a magnificent steam bath that was referred to in Latin as the caldarium. In the Americas, native Americans made heavy use of sweat lodges long before the Spaniards arrived in the 15th century. The Aztec temazcal is the most famous example among them. It was both constructed of and heated with volcanic stone. In the Middle East, the so-called Turkish bath or hammam, invented around the same time, is so famous that today the term “Turkish bath” is often synonymous with steam bath.

12294726276_32c31f8915_h

Steam bath science

In investigating steam bath health benefit claims, Spanking FIT took exactly the same approach as with its dry sauna investigation (See: “Heated medical debate on sauna health benefits“). First, we cited the claims, and then, presented both sides of the issue. Some claimed health benefits of wet sauna are exactly the same as for dry. For that reason, in this study, we concentrated primarily on those benefits believed most relevant to the steam bath. Claim I (steam bath for colds): Use of wet sauna or steam bath may be beneficial in relieving breathing difficulties such as those associated with common colds. They may be used in opening up mucous membranes including sinuses, and those found in the throat and in the lungs. Consequently, they help clear congestion in affected areas. Claim II: Steam bath therapy is beneficial in treating joint problems, and in alleviating the symptoms of certain diseases such as rheumatoid arthritis.

Opponents of therapeutic steam bath use ( the naysayers)

In the case of our dry sauna investigation, Harvey R. Simon. M.D. editor-in-chief of Harvard Men’s Health Watch was a leading doubter of popular health claims. He is alleged by several websites to be a skeptic regarding wet sauna health claims also; but, honestly I was not able to confirm that. However, it’s true that the Columbia University website, goaskalice.columbia expresses a negative opinion on the subject. They state that “neither sauna nor steam exert health benefits”; but, unsupported by research references. Goaskalice.com is a health question and answer internet resource produced by health professionals who are affiliated with Columbia University.

Advocates of therapeutic steam bath use (the yeasayers)

There are a number of websites on internet, including those affiliated with sauna makers, claiming a long list of steam bath benefits. They include thermasol.com and steamspa.co.uk to cite a couple. Among the list of benefits claimed are the following: steam bathing opens up airways in the lungs, increases blood flow, and helps diminish respiratory congestion (essentially, claim I above). They state that it relieves sinusitis, bronchitis, and asthma. These websites frequently make reference to research allegedly conducted in the 1980’s at the Institute of Balneology and Climatology, University of Munich, Germany. (By the way, balneology is defined to be the study of physio chemical properties of mineral water in baths, just in case you were not aware of that!). A laborious effort on our part to find relevant published results from the Institute proved unfruitful.  Also, I have yet to receive a reply from the websites mentioned above regarding my request to them for a citation regarding this research. For the time being, these alleged findings, although reasonable sounding, are on hold. I was, however, able to locate at least one serious publication supporting Claim I: “Local hyperthermia benefits natural and experimental colds” by D. Tyrell, et. al. published in 1989 in the British Medical Journal.  In this paper, researchers at Harvard Hospital in England (not U.S.) reported significant findings based on the results of a randomized double blind experiment regarding the common cold and steam heat therapy. Remember that from a statistical viewpoint, a randomized double blind experiment is generally a good design. A group of common cold patients were randomly divided into “controls” who were exposed to heat, versus “treatments”, who were exposed to even higher heat at the level of what is expected in a standard wet sauna. The treatment group experienced a measurable reduction of symptoms which was also statistically significant. The research team took things further by injecting a group of healthy volunteers with human rhino virus. For those contracting a cold, a similar procedure to above was followed and results obtained were similar. I, for one, am not surprised by these findings. Steam bathing succeeds in bringing warmth to the areas of the anatomy affected by colds and increases blood circulation so, more than likely, it is beneficial in fighting the infection that is the underlying cause of these symptoms. On the other hand, I am quite surprised by the skepticism expressed by many medical practitioners on the subject. Needless to say, wet steam bathing needs to be performed safely and in moderation. One interesting note: Dr. Douglas Linz of Tri Health Fitness and Health Pavilion in Ohio totally disagrees with the previous websites regarding steam sauna  treatment for asthma. He warns that asthma sufferers should avoid the steam room and opt for the dry sauna instead; but, again, his claims are not referenced by research. Who to believe?
Regarding claim II, that steam bathing is therapeutic with respect to joint problems, and in alleviating the symptoms of certain diseases such as rheumatoid arthritis: A number of publications which support this hypothesis emanate from sources all over the world including Turkey, Holland, and Japan. All are limited by certain methodological flaws, even according to their own authors. Clearly, given the great number of persons who suffer from joint problems, and the resulting enormous costs of the medications used to treat them and their side effects, serious formal investigation into simple steam sauna therapy for joint problems is definitely warranted, in my opinion. What do you think?

Which carries greater risks: dry or wet sauna?

There appears to be a paucity of comparative research regarding the health benefits of the two types of sauna bath. However, I did find some serious research out of Poland regarding relative health risks: “Comparison of Physiological Reaction and Physical Strain in Healthy Men Under Heat Stress In Dry And Steam Heat Saunas”, by W. Pilch, et. al. published in the June 2014 issue of Biology of Sport. In their study, “healthy” men aged 25 through 28 years old first underwent dry sauna treatment. A month later, the same men underwent steam. A number of relevant physiological parameters were measured both before and after undergoing the exposures and a comparison was performed. The study concluded that wet sauna, where the humidity is high, causes elevated heat strain for the subjects as evidenced by parameter changes. All results obtained were claimed statistically significant by the authors who appear quite competent in that area, also. A potential problem with wet sauna use is that the high air humidity may cause difficulties in the evaporation of sweat from surface skin slowing down removal of body heat. In other words, one must exercise even greater caution when using the wet sauna, as opposed to the dry. Limit your exposure time and consume lots of fluids. Most important of all, use the steam bath in moderation and listen carefully to your body.   For the results of our dry sauna investigation see : “Heated Medical Debate On Sauna Health Benefits“, Spanking FIT, Dec. 1, 2014.        Dr. Garrett