Sauna is not a recent invention of mankind. In fact, the cradle of the sauna is far from the luxurious spas of today. Ancient civilizations from all parts of the world once made use of rudimentary facilities, with the aim of raising body temperature (hyperthermia) to promote profuse sweating, aware that this powerful mechanism could activate healing processes in the body.
The healing effects of sauna are mainly derived from the activation of the parasympathetic system.
Science has further proven several benefits of regular use of sauna and in particular the use of the infrared sauna, which uses infrared radiation (or light) to increase temperature. It also has more therapeutic effects when compared to steam. 
An integrative approach to treating cancer will never be complete without a detoxification program. Among the different ways to eliminate waste from our bodies, sweat plays a key role. In fact, it has been said that the skin is the main detoxification organ in our body. Heavy metals, phenols, phthalate, medications of chronic use, and many other cancer-causing chemicals are expelled out through our pores when we sweat.
Speeds recovery processes
The use of sauna increases IGF-1, a hormone vital for growth and essential in recovery processes. One study found that IGF1 increased by 142% during the use of an infrared sauna. 
Another study detected a 5-fold increase in Human Growth Hormone (HGH) levels in just two 15-minute infrared sauna sessions per week. 
Improves blood flow
Cancer cells grow and reproduce better in low oxygen environments. Sauna therapy, however, allows for greater absorption of nutrients and oxygen in the areas and organs of the body affected by cancer, thereby making the cancer cells more labile to treatments.
Improves mood and decreases stress levels
It is well known that a bad attitude and negative feelings adversely affect your immune system and promote the development of the disease. Cancer is very much linked to stress and depression. Therefore, the proper treatment of these conditions is essential in the context of an integrative cancer treatment program.
The use of a sauna increases the number of beta-endorphins, which provokes a certain feeling of euphoria or happiness. Thus, heat therapy throughout the body has been shown to improve the symptoms of depression in patients with cancer. 
Not All Stress is Bad
Interestingly, a very long session of a sauna can also be stressful for the body, however, this kind of stress is beneficial, since it generates a hormone response and the release of an opiate called dynorphin, as well as an increase in heat shock proteins. In simple words, this process of “hormesis” enables the body to become “stronger” and in turn, makes it more resistant to toxins, extreme temperatures, and cellular stress caused by disease.
Sauna therapy is so powerful that it can restore and bring back to normality the hypothalamic-pituitary-adrenal (HPA) axis. These are the glands that interact and keep a balance in our stress hormones.
Sauna reduces blood sugar levels
Cancerous cells are eager glucose-eaters and thrive in a high-glucose environment with a high rate of growth and reproduction. In animal models, mice with insulin resistance received 30 minutes of hyperthermia (sauna therapy) three times a week for 12 weeks. At the end of that period, the mice had decreased insulin levels by 31%, due to a lower load of sugar level in blood. The researchers suggest that the use of sauna therapy may increase insulin sensitivity thanks to an abundance of GLUT4 transporters, with blood sugar levels very low. The researchers further suggest that the use of the sauna may increase insulin sensitivity due to an increase in GLUT4 transporters. 
Helps to fight pain
The use of sauna helps alleviate pain, through the increased secretion of several hormones that have anti-inflammatory effects, such as noradrenaline and adrenaline as well as cortisol and IGF-1. It also increases the release of endorphins, our body’s natural analgesics.
Kills cancerous sells
In 1891, Dr. William Coley published an investigation on how fever could benefit cancer patients by stimulating an immune response and causing the remission of cancer.
A study in 2009 found that in just 30 days infrared sauna therapy could reduce the volume of all tumors by 86% in animal models.  Japanese researchers also found that hyperthermia (a term used to describe infrared sauna therapy) stopped the growth of breast cancer in mice without adverse side effects. 
As we can see, the infrared sauna is a beneficial and safe powerful aid in the integrative approach of cancer treatment. 
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