A new study has found that a single sauna session is enough to boost the body’s immune system.
University of Eastern Finland researchers found a single 30-minute sauna session could briefly put the immune system on “higher alert”.
This was achieved because the sauna temporarily moved more white blood cells into the bloodstream.
“These immune cells help the body detect and respond to pathogens and disease.” The study report said.
“Researchers found that a 30-minute sauna session increased the number of every type of circulating white blood cell.”
The effect was even more powerful when it was paired with a short cold shower.
The study involved 51 adults and the findings were published in the journal Temperature.
Academy Research Fellow at the University of Turku, Ilkka Heinonen, said the levels of neutrophils and lymphocytes (important parts of the immune system) returned to their usual levels within about 30 minutes of the sauna ending.
“This may indicate that sauna bathing mobilises additional white blood cells into the bloodstream from tissues, where they are then redeposited after the session,” Dr Heinonen said.
“This kind of periodic release of white blood cells into the bloodstream is beneficial, as once they leave their storage sites, they are better able to patrol the body and respond to pathogens.”
Dr Heinonen said a similar release of white blood cells happened during physical exercise.
“By sending more of these cells into circulation, the body may improve immune surveillance and strengthen its ability to respond to possible threats,” he said.
The research report said regular sauna use had previously been linked to a range of health benefits.
This latest study could enhance the understanding of some of the biological processes behind those benefits.
The researchers said the study only measured the immediate effects of a single sauna session.
The findings could not establish whether repeated sauna bathing produced lasting changes.
The full study is here
