Where I live in Seattle, August is the perfect month to get outdoors, enjoy the sun, and do some good old-fashioned sweating. For some ultra-therapeutic sweating, I’m hoping to make it to the mountains and hike up to some hot springs this month. But I’ll also be doing some day-to-day sweat-inducing outdoor activities, like walking or running around my neighborhood and working in my garden. I realize, of course, that in other parts of the country, August is a month of uncomfortable heat and you’re better off exercising in the air conditioned indoors during the hottest parts of the day. Wherever you are, though, it is important to sweat.
Sweating for Optimal Health
New research is revealing remarkable information about why the body sweats. Sweating is most widely known for its importance in cooling the surface of the skin to reduce body temperature, but that’s just the beginning. It leads to a number of other beneficial physiological changes and even helps eliminate accumulated toxins. Sweating for Detoxification
The skin is a major organ of detoxification and a vast array of toxic compounds can be excreted via perspiration.[1,2] In fact, many toxins are preferentially excreted through sweat.2 Studies have confirmed that body levels of many toxic compounds diminish with therapy to induce sweating. While sweating has long been known as a source of bodily and spiritual cleansing, until recently, very little scientific evidence existed to show that perspiration-induced detoxification actually works. But there is now compelling evidence pointing to the validity of this therapy. Heavy Metal
Detox via Sweat
A groundbreaking 2011 study published in the Archives of Environmental and Contamination Toxicology explored the effects of toxic heavy metals that accumulate within the human body and their methods of excretion. Although researchers detected the presence of toxic elements in people’s blood, urine, and sweat, they found that many toxic elements appeared to be preferentially excreted through sweat. In fact, some toxic elements that are stored in body tissues showed up only in the perspiration but not the blood or urine. “Induced sweating appears to be a potential method for elimination of many toxic elements from the human body,” concluded the researchers. A 2012 study published in the Journal of Public and Environmental Health titled, “Arsenic, cadmium, lead, and mercury in sweat: a systematic review,” was based on a review of 24 studies on toxicant levels in the sweat. The researchers discovered that in people with higher exposure or body burden, sweat generally exceeded plasma or urine concentrations, and excretion of these metals through the skin via sweat could match or surpass urinary daily excretion. The researchers concluded, “Sweating deserves consideration for toxic element detoxification.”
Detox of BPA and Phthalates
It’s not only heavy metals that you eliminate by sweating. Two studies published in 2012 found that sweating enhances the elimination of the endocrine-disrupting petrochemicals bisphenol A (BPA) and phthalates. The first study, involving 20 subjects who underwent induced sweating, found that the ubiquitous BPA was excreted through sweat, even in some people with no BPA detected in their serum or urine samples. The results clearly indicate that the body uses sweat to rid itself of BPA that has bioaccumulated in tissue. The second study by the same research group, also involving 20 subjects, found that phthalate, a plasticizer tied to breast cancer and various other conditions associated with endocrine disruption, was present in concentrations twice as high in subjects’ sweat compared to their urine. In several people, phthalate was found in sweat but not in blood serum, suggesting the possibility of phthalate retention and bioaccumulation. “Induced perspiration may be useful to facilitate elimination of some potentially toxic phthalate compounds,” the researchers concluded.
Body Temperature Benefits
Sweating and body temperature elevation go hand-in-hand. Some of the benefits of sweating are actually more related to increased body temperatures than they are to perspiration. Purposely increasing body temperature to the range of 100° to 105° F for therapeutic purposes is called hyperthermia. Hyperthermia has various physiologic effects that enhance healing, circulation, and immune function. Elevated body temperatures have been recognized as beneficial for the immune system’s defenses against pathogens since ancient times, and the notion of treating cancer with heat dates back to the writings of Hippocrates. Recent research has confirmed these early beliefs, showing that mildly increasing body temperature increases white blood cell production and kills tumors and pathogens.[6,7] Mild hyperthermia preferentially kills malignant cancer cells through complex biological reactions including stimulation of immune responses (cancer-killing immune cells, called natural killer cells, are increased), programmed cell death, and synergistic effects with other cancer treatments.[6,8] Hyperthermia has been found in human studies to enhance the effects of chemotherapy and radiation therapy and is now being used in cancer treatment centers along with these conventional treatments.8 The immune effects of hyperthermia may translate into decreased incidence of infections. Repeated sauna use cut the frequency of common colds by half in one small study.
Fascinating Sauna Therapy Research
In clinical studies, sauna therapy has been found to benefit numerous medical conditions:
- cardiovascular diseases (hypertension, congestive heart failure, and care after heart attack)[1-3]
- respiratory diseases (chronic obstructive pulmonary disease)
- allergies (allergic rhinitis)
- quality of life in type 2 diabetes
- joint disease (rheumatoid arthritis and ankylosing spondylitis)
- chronic pain
- chronic fatigue
In addition, sauna therapy has been found to:
- decrease total and LDL cholesterol
- induce physical relaxation as well as a subjective feeling of calmness10
- increase recovery from muscle fatigue
- increase the stability and restore the structure of blood cell membranes
- activate antioxidant protection
- regenerate oxidant-antioxidant balance after exercise
- stimulate the immune system by increasing white blood cell counts.
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