Harvard about sauna

Sauna has a long history. The Mayans of Central America, about 3000 years ago, used sweat houses for religious ceremonies and good health. Ancient Roman baths were an inspiration for modern Turkish steam baths. One of the oldest, and still popular today are Finnish saunas. However, saunas are increasingly popular all around the world. Experts on Harvard make their opinion about using saunas. If you’re interested in benefits of infrared saunas,read here.

Wooden box

The modern sauna is a simple room with wooden walls and benches on one or more levels. The electric heater keeps the temperature at about 100°C. This type of sauna has a low level of humidity from 10 % to 20 %. If sauna has an efficient ventilation system, air exchanges three to eight times an hour.

Human’s body in the sauna

Sweating begins on the dry heat immediately. The problem is that a person may not realize how much he is perspiring, while skin temperature soars to about 37°C within minutes. Internal body temperature rises more slowly, usually stays below 37°C.

The pulse rate jumps by 30 %, and the result is double the amount of blood it pumps each minute. The extra blood flow is directed to the skin, all of the changes resolve quickly after a person cools down.

Sauna and heart

Finnish researchers found that of 1631 heart attacks in Helsinki just 1.8 % developed within three hours of taking a sauna. Another investigation found that all of 6175 sudden deaths, only 1.7 % occurred within 24 hours of taking a sauna – many of those were related to alcohol. Do not overdo sauna, and do not mix sauna and alcohol.

On the other hand, Canadian research investigated sauna safety in 16 patients with heart disease. They compared the effects of a 15-minute sauna with a standard treadmill stress test. None of the patients developed chest pain, abnormal heart rhythms or ECG changes with either type of stress. Heart scans did show impaired blood flow to the heart muscles of most patients, but the sauna-induced changes were milder than the exercise-induced abnormalities.

The third case comes from Japan. The research found that sauna appears safe for patients with stable coronary artery disease. Conclusion of this research is: two weeks of daily saunas may even improve vascular function in patients with mildly damaged hearts that cannot pump blood normally.

Still, heart patients should check with their doctors before using saunas.

Sauna and other organs

There is no evidence that regular saunas impair fertility, but elevated scrotal temperatures reduce sperm production. The dry air doesn’t harm the skin or lungs, or in case of psoriasis, report relief from itching. Asthmatics may experience less wheezing, too.

Hot tub

Lower temperature and higher humidity are characteristic of a hot tub. A study of 15 men with stable coronary artery disease showed that 15 minutes in a hot tub produced less circulatory stress than 15 minutes on a stationary bike. Moreover, a study of 21 people with hypertension found that while sitting in a hot tub lowered the blood pressure, it never approached unsafe levels.

Guidelines for hot tub and saunas are the same. Additionally, be sure the tub is clean and well chlorinated to avoid folliculitis.

Precautions to have sauna safety

  • Avoid alcohol before and after sauna
  • Do not stay longer than 15 minutes in the sauna
  • Cool down gradually afterward. If you don’t have experience don’t advocate a plunge into cold water
  • Don’t forget water! Drink two to four glasses of cool water after each sauna, and listen to your body
  • If you’re ill, of you feel unwell during your sauna, avoid the sauna. A cool head is the best way to keep your hot sauna safe and enjoyable