Sauna & Health
Sweat Bathing and the Body
©2011 Mikkel Aaland All Rights Reserved
"Give me a fever and I can cure any disease."
SWEATING | SKIN | HEATING & COOLING THE INNER BODY | POSITIIVE EFFECTS OF NEGATIVE IONS |SPIRITS OF THE SWEAT BATH | SOCIAL SWEATING
Sweat on my fingertip. Magnification 90x, scanning electron
microscopy by J.R. Swafford, Arizona State University.
Sitting in a sweat bath could be the most vigorous activity you've
had all day. The heat produces an artificial "fever" and urges
every organ of the body into action. While outwardly relaxed,
your inner organs are as active as though you were jogging or
mowing the lawn. At the same time, you are being cleansed from
inside out by the skin, your body's largest organ and its excretion,
The oldest know medical document, the Ayurveda, appeared in Sanskrit
in 568 BC and considered sweating so important to health that
it prescribed the sweat bath and thirteen other methods of inducing
sweat. Throughout history physicians have extolled the medicinal
value of the sweat bath in its various forms such as the Finnish
sauna, Russian banai, Islamic hammam, or the American Indian sweatlodge.
Today, enthusiasts claim that beyond being relaxing the sauna
gives relief from the common cold, arthritis, headaches, hangovers
and "just about anything that ails you." Even if these claims
are somewhat exaggerated, medical evidence shows that bathing
in temperatures of 9O degrees C (192 degrees F) has a profoundly
beneficial effect on a healthy body. *
*Medical researchers in Finland, Germany and, recently, the United
States have made intensive studies on the phenomenon of sweating
and heating the body. Since much of this research is still in
progress, many results are still inconclusive. The author has
drawn from many sources and the information sometimes has been
controversial or debatable which he duly notes in this section.
2011 Update: Build Your Own Sweat
I just released a new eBook titled How to Build Your Own Sauna & Sweat. It's available for instant download ( $9.99) for the Kindle and the Nook (more formats to follow).
Sweating is as essential to our health as eating and breathing.
It accomplishes three important things: rids the body of wastes,
regulates the critical temperature of the body at 37 degrees C
(98.6 degrees F), and helps keep the skin clean and pliant.
Many people, in this sedentary age, simply don't sweat enough,
making sweat bathing particularly desirable during these times.
Antiperspirants, artificial environments, smog, synthetic clothing,
and a physically idle lifestyle all conspire to clog skin pores
and inhibit the healthy flow of sweat. These detrimental effects
are reversed in a sweat bath.*
[*The physiological effects of different sweat baths are not the
same, due to variations in heat and humidity. For example, the
body sweats more profusely in the hotter (80-100 degree C) and
drier (15-25%) atmosphere of the Turkish bath, where moisture
on your body is often merely condensation. The length of time
spent in the sauna differs from time spent in other types of sweat
baths. In this section, results peculiar to the sauna are noted.]
When you lounge in a sweat bath, heat sensitive nerve endings
produce acetylcholine, a chemical which alerts the 2.3 million
sweat glands embedded in the skin. But not all of them respond.
The aprocine sweat glands, located in the pubic and arm pit areas,
are activated only by emotional stimuli. They carry a faint scent
whose purpose is believed to arouse the sex drive.
Nevertheless, the eccrine sweat glands, by far the most abundant,
respond to heat. During a 15-minute sauna, about one liter of
sweat is excreted, depending upon the individual. (Normal daily
rate ranges from .5 to 1.5 liters.) Eccrine sweat is clear and
odorless; any odor is only created by the presence of bacteria.
One of its chief functions is to cool the body by evaporation,
although there are also eccrine glands on the palms of your hands
and soles of your feet which react to emotional stimuli. Like
the baseball batter who wets his hands for a better grip, it is
believed these sweat glands were intended to provide us with a
good grip on clubs, rocks or vines when our survival often depended
upon them. Sweat glands on the feet provided greater traction
when it came time to run.
A third kind of sweat, called insensible perspiration, originates
inside and works its way through blood and other cells to the
surface of the skin. Even without a sweat bath, approximately
a liter of insensible perspiration evaporates each day.
A modified type of sweat gland is the milk-producing mammary gland.
Some mothers in Finland believe the sauna encourages the breast's
ability to produce milk, although this hasn't been established
Sweat also has the function of being a judicious garbage collector.
During a 15-minute sauna, sweating can perform the heavy metal
excretion that would take the kidneys 24 working hours. Ninety-nine
percent of what sweat brings to the surface of the skin is water,
but the remaining one percent is mostly undesirable wastes. Excessive
salt carried by sweat is generally believed to be beneficial for
cases of mild hypertension. Some mental hospitals use saunas in
their rehabilitation programs to pacify patients.
A metabolic by-product, urea, if not disposed of regularly, can
cause headaches, nausea and, in extreme cases, vomiting, coma
and even death. Sweating is such an effective de-toxifier that
some physicians recommend home saunas to supplement kidney machines.
Sweat also draws out lactic acid which causes stiff muscles and
contributes to general fatigue. Sweat flushes out toxic metals
such as copper, lead, zinc and mercury which the body absorbs
in polluted environments.
Because it eliminates, the skin is sometimes called the "third
kidney." It is far more complex than the kidney or any other organ
except the brain. It is composed of blood vessels, nerve endings,
vessels for carrying Iymph, pigmentation, oil glands, hair follicles,
cells that waterproof and deny entry to bacteria and, of course,
the tubular, coiled sweat glands. It is so important that death
by accumulated poisons occurs in a matter of hours if the skin,
and its sweat passages, are smothered.
A Finnish doctor wrote: "The best-dressed of foreigners can come
into a doctor's office, and when his skin is examined, it is found
to be rough as bark. On the other hand, as a result of the sauna,
the skin of any Finnish worker is supple and healthy." Properly
cared for skin is better able to resist eczema, athlete's foot,
pimples and blackheads.
Furthermore, combining sweat bathing and brushing with a loofa
or rough brush removes flakes of dried skin cells that accumulate
on the epidermis. If allowed to remain, they can clog sweat pores
and oil passages and result in dry, flaky skin.
In conjunction with the sweat bath exercise, supplemental dosages
of vitamins B2 and E help keep skin fresh. Cayenne pepper, ginger,
peppermint are notable herbs which, when taken internally, promote
sweating and healthy skin.
(An interesting note: the ability of lizards and snakes to shed
old skins has fascinated many primitive societies. Some believe
that if they could shed their old skins and acquire new ones,
they could renew their youth. During some ceremonies, participants
don the skins of animals or other human beings in a symbolic gesture
of eternal youth.)
Heating and Cooling the Inner Body
Marvelous things happen beneath the skin in the heat of the sweat
bath. The capillaries dilate permitting increased flow of blood
to the skin in an attempt to draw heat from the surface and disperse
it inside the body. The bather's skin becomes cherry red. The
heart is pressed into a faster pace to keep up with the additional
demands for blood. Impurities in the liver, kidneys, stomach,
muscles, brain, and most other organs are flushed out by the faster
flow of juices. The skin and kidneys filter the wastes, excreting
them in sweat and urine.
Some researchers claim that the rapid flexing of the heart and
blood vessels in the heat of the sweat bath is a healthy exercise
that puts little more strain on the heart than strolling on level
ground. The increased capillary volume, they say, keeps blood
pressure normal. Other medical people, however, qualify their
commendations. One Finnish study observed that whereas blood pressure
of healthy persons remains approximately normal in a sweat bath,
there occurs a marked reduction of pressure in persons suffering
from high blood pressure. However, this effect is only transient,
and the original condition returns soon after the sweat bath.
American doctors commonly recommend that elderly people and persons
with heart problems should avoid sweat bathing. Finnish and German
doctors feel otherwise. Perhaps this difference of opinion arises
from the fact that the Germans and especially the Finns are more
familiar with sweat bathing.
While the surface temperature of the skin may rise as much as
1O degrees C, inner temperature increases up to 3 degrees C. This
is the "fever" that Hippocrates and generations of medical people
after him sought, and is created as one reclines in a sweat bath!
Of course it is unlikely that "any disease" can be cured by fever,
but it is common knowledge that many bacterial and viral agents
do not survive well at temperatures higher than normal body temperature.
It is also possible that damaged cells repair themselves quicker
in fever conditions due to the increased metabolic rate. Recovery
from illness then comes easier and quicker.
The inner temperature rise also affects the function of important
endocrine glands, the pituitary in particular. Located in the
bottom center of the brain, the pituitary is known as the master
gland because its hormones regulate both metabolism and the activity
of other glands such as the thyroid, adrenal, ovaries and testes.
Urged by the heat, the pituitary accelerates the body's metabolism
and affects the interplay of several of the body's hormones. Some
people have gone as far to say that sex drive is increased and
growth stimulated in the sauna bath.
The oxygen needs of the body increase by about 2O percent so the
lungs, another important eliminator of body wastes, join in the
body's quickened pace. (The lungs' rapid exchange of carbon dioxide
for oxygen is hindered in some sweat baths. In high humidity water
condenses on the tiny alveoli where this exchange takes place
and breathing may be slightly more difficult. On the other hand,
if the air is too dry, as occurs in many American saunas, mucous
membranes may become dry and damaged.) Clogged respiratory passages
are opened by heat, giving relief from colds and other minor respiratory
problems. Sweat bathing is not recommended for those suffering
from pneumonia or other acute respiratory diseases.
When the bocly is slowly cooled, the effects of heat are reversed--the
heart calms, sweat pores close, dilated blood vessels contract
and body temperature returns to normal. (The German Sauna Society
recommends a warm foot bath to re-open closed blood vessels.)
On the other hand, abrupt cooling brought on by a plunge into
snow or icy water creates a more dramatic effect. For this reason,
people with weak constitutions should avoid rapid cooling. Vessels
near the skin's surface contract, but since the skin's metabolism
returns to normal slower than the circulatory system, wastes accumulate
that are normally washed out by the blood. Local vasodilators
are then stimulated and blood rushes back to the skin's surface.
The heart continues to beat vigorously and you may experience
psychedelic flashes bouncing across your retina from the increased
adrenal activity--an unforgettable experience! Goose bumps sometimes
appear, a phenomenon reminiscent of the time when our prehistoric
ancestors possessed a shaggy pelt of hair. Goose bumps extended
the hair, making it thicker and giving more insulating power against
cold or protection from attack. The swift transition from hot
to cold stimulates the kidneys and usually creates the desire
The typical body is 6O% water by weight and any pounds lost at
this point will be promptly regained. (However, sweat baths have
an indirect effect on weight loss--see appendix.) As you can imagine,
the combination of sweat bathing and cooling conditions the body,
and a well-tuned body is more resistant to colds, disease and
infection. In cold weather, the warm glowing feeling lingers for
hours, while in hot climates the body seems cooler than before
the sweat bath. (See chapter 3.)
Positive Effects of Negative Ions
Physiologically, the presence of negative ions in a sweat bath
is as important as the heat. The discovery of negative ions in
certain types of saunas a few years ago became headline news in
Finland. Until then, the healing power of the sauna was attributed
to relaxation and increased circulation. Now, negative ions add
startling new possibilities.
Since the early 1950s scientists have suspected that ions play
an important role in how the body functions and, consequently,
in how we feel. Research has shown that an abundance of negative
ions ln the air we breathe is highly beneficial, while a lack
of ions or a higher ratio of positive to negative can cause physical
harm. The role played by ions in everyday life has become intensely
topical among researchers in the medical profession. (Read The
Ion Effect by Fred Soyka for an excellent discussion on the use
of negaive ions in medicine.)
An ion is simply a molecule with an electric charge, either positive
or negative. Ionization, or ion formation, occurs when enough
energy acts on a molecule to cause it to discharge an electron.
Because electrons carry a negative charge, the molecule stripped
of an electron has a greater positive charge and becomes a positive
ion. The lost electron scoots around loose until it attaches itself
to another molecule which causes the new molecule to become negatively
charged--a negative ion.
Radioactive substances in the earth's crust and cosmic rays cause
most ionization. But fire, crashing water (like water falls and
surf), and plants during photosynthesis can produce negative ions
as well. Europeans take ion depletions seriously and simple negative
ion generators have been installed in many businesses, banks,
hospitals, and passenger cars and even airliner cockpits. Furthermore,
in this country, Europe and the Soviet Union, negative ion therapy
has been used in treatments to help burn victims heal faster,
to cure respiratory diseases, to rid the body of general infections,
and even to check the spread of some cancers.
Conversely, scientists have found that if the air is charged with
too few negative ions and too many positives, we become anxious,
fatigued and tense. This condition is known as "pos-ion poisoning,"
and often occurs as the result of weather disturbances, central
air conditioning, smog, and driving too long within the confines
of an automobile. Pos-ion poisoning has, in fact, been linked
to heart attacks, aggravated asthma, migraine headaches, insomnia,
rheumatism, arthritis, hay fever, and most allergies.
The effect of negative ions on sweat bathing was discovered when
researchers were trying to account for the tremendous popularity
of sauna wood burning stoves over electric stoves. Subjective
reasons, such as the fragrance of burned wood, did not fully explain
why Finns felt so refreshed after time in a wood heated sauna
and quite dulled, from certain electrically heated saunas. Tests
showed that the practice of splashing water on super-heated rocks
produced an abundance of negative ions. Many electric stoves,
it turned out, were not getting the rocks hot enough and the glowing
metal heating coils were spurting more positive ions in the air.
Researchers learned that if the rocks were properly heated in
electric stoves, the positive ions, being larger and less mobile,
would ground out on the hot stones. The buying habits of the Finns,
perhaps the most sophisticated of sweat bathers, has forced many
Finnish electric stove companies to pay particular attention to
their sauna stove design. Researchers also cited poor ventilation
in modern saunas as a cause of positive ion buildup; but, for
a discussion of the proper climatic conditions for a sauna please
refer to the appendix material on construction and use. A more
detailed study regarding ions and saunas can be found in Sauna
Studies, published by the Sauna Society of Finland, 1977.
Although tests have not been conducted on other sweat baths, it
is likely similar negative ion production occurs in any sweat
bath that converts water to vapor quickly. The Native American
Indian sweat lodge comes to mind.
The further effects of sweat bathing and the body are discussed
in the appendix: sports, women (menstruation, pregnancy, menopause),
arthritis, rheumatism, sleep, hangover, weight reduction, children
Spirits of the Sweat Bath: Born of Fire
Whether shining in heaven or burning in hell, fire has always
commanded reverence. For stealing fire from the gods and delivering
it to humans, Prometheus was credited by the Greeks with the founding
of civilization. The Navajos say that fire's color is sinister,
a dangerous element of war and sorcery. They often combine red
with black. Yet for the Navajos, and most cultures, fire is also
the color of power, vigor and vitality. The sweat house, by housing
and controlling the awesome power of flame, became a sacred shrine.
Early sauna bathers in Finland believed fire was heaven sent and
if fueled with choice firewood and tended to with appropriate
ritual, diseases and spiritual evils could be driven off. If treated
disrespectfully, fire could engulf and destroy the bather.
Many sweat bath cultures discovered that rocks could absorb the
power of fire, and thereby acquired spiritual significance. The
Omaha Indians, for example, referred to the rocks as Grandfather,
symbol of earthly endurance, and moved them from the fire into
the revered sweatlodge. When water was splashed over them, the
vapor produced became another medium for the transfer of heat
and another object of worship. The Finns named this vapor loyly,
spirit of life. The Fox, another American Indian tribe, believed
that Manitou, a friendly spirit, dwelled inside the rocks and
was released through the vapor to penetrate the skins of the bathers
and drive out sickness. (Science has given a new name to vapor's
healing power--negative ions.)
A bather absorbing the heat of a sweat bath was seen as re-enacting
Creation, merging body and fire. Hindu mythology has several stories
regarding the human absorption of heat. Pajapati created the world
by heating himself to an extreme temperature through asceticism.
Consequently, Hindu ascetics meditate near fire to achieve inner
heat. Those who reach a communion with the Spirit are said to
"burn." Those who perform miracles are called sahib-jocks, which
means to "boil" from inner heat.
The visible product of heat, or "waters born from the heated man,"
is sweat. When looked on in this spiritual light, sweat's importance
to many primitive societies becomes clear. New Guinea tribes believed
that sweat carried the combined essences of spiritual and human
powers. Before leaving a campsite, they would carefully stab the
ground with spears to prevent a demon from making use of any of
their precious fluids they may have left behind. On Warrior Island
in the Torres Straits, men would drink the sweat of renowned warriors
so they too might become strong and fearless. Another example
of sweat's mystical powers comes from Russia where peasants would
concoct an aphrodisiac with vodka and sweat from the bride-to-be.
Sweat, because of its indirect association with fire, was sometimes
connected with the creation of humankind. Sweat from bathing gods
is of special importance. In Russian and Indian folklore are tales
of "God" in a sweat bath and creating "Adam and Eve" through drops
of falling sweat. A Bengali tale indicates another culture that
believed that sweat carries the seeds of life: "Siva (a Hindu
god) sweat and he washed the sweat away with a piece of cloth.
He threw the cloth away. out of this a girl was born."
Perhaps another explanation for the sweat bath's spirituality
is its association with re-birth. The rejuvenating effects of
the sweat bath, combined with its physical characteristics, made
it a natural place for purification and rebirth rituals. The warm,
dark, moist ambiance inside a sweat bath is easily likened to
a womb, even the womb of Mother Earth herself. A tired, dirty
bather climbs into the confines of the sweat bath, assumes a fetal
position (especially in the smaller, more primitive baths), sweats
out physical and spiritual impurities and emerges refreshed and
Because of these re-birth qualities, rites of passage were invariably
connected with sweat bathing. Cleanliness is next to godliness,
and close to God is a good place to be when an individual passes
from one stage of life to another. The sweat bath prepared bathers
for the rituals that attended birth, adulthood, marriage and death
rites of passage; times when awe of the unknown was highest.
Finnish women usually gave birth inside saunas in order to be
in the presence of benevolent spirits. These spirits were thought
to reduce the pains of childbirth and increase the chance of survival
for both the mother and child.
When a boy reached puberty among the Thompson Indians of British
Columbia, he entered the sweat bath to pray to the "sweat bathing
Grandfather Chief." He prayed that he might be strong, brave,
and agile, a good hunter and fisherman, lucky and prosperous.
Islamic women went to the hamman, the middle eastern sweat bath,
three times during many days of wedding ceremonies, attending
the final rinsing bath on the eve of marriage.
Russian mourners would heat their sweat bath in order to warm
their living souls and, by projection, the souls of the deceased.
Finally, as with any religion or ritual, sweat baths would not
have been given such cultural importance without serving humankind
in practical ways. With its mystical powers marshalled, the sweat
bath became healer. We've seen how modern science attempts to
explain its healing powers, but before people knew that bacteria
thrived in blood and filth and were responsible for disease, people
believed that evil spirits were the cause of ill health. So instead
of relying on the antiseptic properties of fire, people called
on the spirits of fire to purge their bodies of demonry. Benevolent
sweat bath spirits drove aches and pains from the body through
the medium of sweat.
The idea is not to have the best sauna on the block, but to get
the entire block in the sauna.
-Professor Harold Tier
President, Finnish Sauna Society
The medicinal and spiritual values of the sweat bath are furthered
by its communal character. The sweat bath is a social event--like
the coffee shop, neighborhood bar or picnic--and is probably the
healthiest ever offered a group of people.
Early in its history, sweat bath ceremonies and rituals were strong
expressions of the community. Elders of' the Cherokee tribe used
the sweat bath as a hallowed schoolhouse where teachinings of'
their forefathers were passed on to their young. Groups of Finns,
dodging elves, would gather inside the sauna to talk, to escape
the Nordic cold and to soothe aching muscles. Turkish women would
congregate for hours in their hamman, the only place their men
allowed them to socialize. The gregarious Romans would throng
by the thousands to their lavish thermaes.
The Russians say, "If there are few banias, we live in unity;
but if there are too many, we are lonely because one does not
visit the other."
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