x
So, why would one swelter in a sauna? I find it pleasant but not everyone has the same level of heat tolerance (more on that below). It turns out heat and sweating alone have many positive health benefits. According to Dr. Rhonda Patrick, the benefits of heat conditioning in a sauna include:
A review of all of the published scientific literature about saunas shows a strong trend of coronary benefits, most notably in their ability to help normalize blood pressure and reduce the chance of congestive heart failure. In fact, a Harvard review of data showed a potential 40+% reduction in heart attack risk from using a sauna 4-7 times per week. And the benefit went up with increased use. In other words, the study showed that the more often and the longer amount of time a person uses a sauna, the more benefit and on average, the longer that person lives.
Heat conditioning or sauna use resembles cardiovascular exercise in many ways, because the cardiovascular system has to work harder to eliminate the heat. Not only does it increase blood flow, sweating, and cardiovascular fitness, but it also leads to a post-exercise euphoria where you feel relaxed, happy, and experience less pain.
An increase in circulation and sweating can aid in detoxification, and in this way sauna therapy helps the body’s natural process of detoxification through sweating.
There is also some evidence that sweating might help reduce heavy metals in the body. A systematic review in 2012 found that toxic heavy metals like arsenic, cadmium, lead, and mercury are found in sweats of people who are exposed to these harmful metals. In a case report, they found that mercury levels normalized with repeated sauna treatments. Again, this benefit is likely due to the sweating and not any special mechanism of the sauna itself.
Saunas increase heat shock proteins, antioxidant enzymes, and stimulate cellular cleanup (autophagy), which can help our cells function like new. In aging mice, an increase in heat shock proteins help delay aging and improves cognitive function.
Sauna bathing can also increase several anti-aging hormones including human growth hormones and the insulin-growth factor 1. IGF-1, in particular, can really help with injury healing.
Several heat-shock proteins can even help with increasing muscle mass, even without weight training. Through photobiomodulation, infrared therapy has a powerful anti-inflammatory effect that can accelerate injury healing.
This is the reason that many people, including Lady Gaga, turn to saunas for pain relief.
Just as when you go for a run, sauna use increases endorphins (the happiness hormone) and opiods (the body’s natural pain reliever), as well as a molecule called brain-derived neurotrophic factor (BDNF) in the brain.
BDNF stimulates neurogenesis (the growth of new neuronal cells) in the brain and protects new neurons from damage. Improving BDNF levels is therefore important for cognitive function. In addition, low or abnormal levels of BDNF may be a cause of several mental and psychiatric diseases.
Infrared saunas can also reduce stress by re-balancing the stress response axis. It can help lower cortisol, and thus helps with stress-related health problems. Saunas also improve the neurotransmitter called norepinephrine, which can help improve cognitive performance.
Contrary to popular claims, heat and sauna use do not directly burn fat or kill fat cells. However, saunas can help improve insulin sensitivity, increase lean muscles, and reduce fat by changing the hormonal environment. In addition, the saunas also reduce inflammation. Therefore, sauna therapies can prevent obesity, diabetes, and cardiovascular diseases.
A Japanese study found that two weeks of sauna therapy increased appetite and food intake in people of a healthy weight. However, in overweight people, far infrared sauna usage together with a low-calorie diet resulted in significant weight and body fat loss. While this study did not compare the fat loss with a group that did not use the sauna, the reduction in body fat (4.5%) in about two week’s time is considered very fast.
As mentioned above, sauna use may increase the presence of heat shock proteins, which are anti-inflammatory. For this reason, saunas may help lower chronic inflammation. Since inflammation is connected to almost every major disease, this is a big deal!
Study participants who used saunas regularly shower lower levels of oxidative stress, even within two weeks! Another study found that men who used the sauna 4-7 times a week had 32% lower levels of c-reactive protein (CRP).
According to Dr. Michael Breus, a clinical psychologist with a board certification in sleep medicine, the steep drop in body temperature at night is one of the circadian cues that the body takes that it is time to sleep. This explains why a warm bath or a shower before bed can improve sleep quality. Because the sauna typically heats the body up much hotter than a warm shower, it can take the body a few hours to cool down for bed. In order to improve your sleep quality, consider using a sauna session in the afternoon or before dinner in order to allow the body to cool down by bedtime.
A Japanese study also found that far-infrared ray exposure improved sleep quality in both rats and an insomniac human subject.
In order to eliminate heat, your body increases blood flow to the skin. In addition, the skin adapts to this process, making it healthier. A German study found that the skin of regular saunas users could better hold moisture and maintain a healthy skin pH. In addition, these sauna users had less sebum on their foreheads, suggesting that they were less likely to get acne.
Skin problems like eczema and psoriasis involves both inflammation and a vulnerability of the skin barrier. By helping both with strengthening the skin barrier and reducing overall inflammation, infrared sauna, if tolerated, can really help with these skin issues. (If sweat significantly irritates the rash, then you may want to protect the rashes with a eczema-friendly lotion and shower right after the sauna.)
.png)
