Sweating rids the body of wastes. In this modern sedentary age of pollution, artificial environments, synthetic clothing and lack of regular exercise, a sweat bath can open clogged skin pores and stimulate the healthy flow of a body's own natural sweat.
Depending on how hot the sweat bath is and the climate in which it occurs, a fifteen minute sauna or sweat can perform the heavy metal excretion that normally takes healthy kidneys 24 hours to accomplish. Body sweat flushes toxic metals such as copper, lead, zinc, and mercury from the body. A sauna is often recommended as a supplement to kidney machines. Sweat can also remove excessive salts; this is generally believed to be beneficial for cases of mild hypertension. Sweat can also eliminate urea, a metabolic by-product. Excessive urea can cause headaches, nausea and in extreme cases, vomiting, coma--even death. Sweat may also draw out lactic acid responsible for stiff muscles and a contributor to general fatigue.
Sweat lodge heat dilates capillaries; this increases blood flow to the skin. The heart beats faster and impurities in vital organs are flushed out by the flow of fluids. Finnish and German doctors cite studies indicating sweat baths help persons with high blood pressure and heart problems; many American doctors, however, continue to recommend against sweat baths for such persons.
Lungs benefit, too. Clogged respiratory passages are opened by heat; this gives relief from colds or minor respiratory problems. Sweat baths are not recommended for persons with pneumonia and major respiratory problems. The heat of a sweat bath and the often rapid cooling afterwards, conditions the body. A well-tuned body is more resistant to colds, disease and infection. In cold weather, a warm glowing feeling often lingers for hours following a sweat bath. In hot weather, the body seems cooler afterwards.