Health Benefits of Sauna
During a 10-20 minute sauna session, the
heart rate increases by 50-75%. This
provides the same metabolic result as
physical exercise. The increased cardiac
load is the equivalent to a brisk walk.
There is a nominal effect on
blood pressure because the heat also causes
blood vessels in skin to expand to
accommodate increased blood flow.
Blood vessels become more flexible and there is increased circulation to the extremities. During a sauna, blood flow to the skin increases to as high as 50-70% of cardiac output (compared to the standard 5-10%). This is due to the blood vessels in the skin's surface expanding to accommodate the increased blood flow, a process known as vasodilation. This increased blood flow brings important nutrients to subcutaneous and surface tissue, promoting cellular activity and growth. It is especially beneficial to areas of the skin which normally suffer from poor circulation. Along with nourishing the skin, the high temperatures also cause the skin's 2 million eccrine glands to excrete sweat to cool down the skin and blood capillaries. Research has shown that sweat is much more effective than water at emulsifying fat located in the skin's sebaceous glands, and thus at removing the sebum and bacteria lodged in the fat. The vasodilation caused by the high temperatures also allow essential fluids to be transported to the skin's surface. This enhances the development of collagen, giving the skin a continued elasticity and wrinkle-free complexion.
Steambaths and saunas induce sweating to provide a comprehensive cleansing of the skin and sweat glands. Skin is the largest organ in the body. 30% of body wastes are passed through the skin. Profuse sweating enhances the detoxifying capacity of the skin by opening pores and flushing impurities from the body. Researchers have often found that the towels smokers use to sit on in saunas turn yellow as a result of the skin removing impurities and toxins.
When taking a sauna, skin temperature rises to 40°C (104°F) and internal body temperature rises to about 38°C (100.4°F). Exposure to the high heat creates an artificial fever state, a process known as hyperthermia. Fever is part of the body’s natural healing process. Fever stimulates the immune system, resulting in increased production of disease fighting white blood cells, antibodies and interferon (an anti viral protein with cancer fighting capability).
Steam inhalation is an excellent treatment for many respiratory problems. For example, the moist air in saunas can relieve throat irritation. Steam also loosens secretions and can stimulate discharge of mucous from the lungs and throat, giving relief to sufferers of bronchitis. Finally steam can also aid sinusitis by relieving congestion and inflammation of the upper respiratory mucous membranes.
The heat also kills all kinds of bacteria and insects, e.g. lice. This knowledge was used widely during the Winter War and Continuation War when Finnish troops were forced to sauna (although with the unclean conditions in the field made it unnecessary to force them). While the men were in their sauna, their equipment was in another. This cleansed both very effectively while Russians had problems with many diseases.
However, it should be noted, people with heart problems may be at risk due to blood pressure unpredictably rising or lowering after using a sauna. People with stable coronary artery disease are generally safe in a sauna, but people with uncontrollable heart problems may be advised to stay away from a Sauna by a doctor in order to avoid possible complications. People with autoimmune disorders may also be at risk.
