Health》Not a Supplement: Study Finds This Sauna Routine Can Temporarily Boost Immune Cells

A 30-minute sauna session may briefly increase the number of infection-fighting white blood cells in the bloodstream, according to a Finnish study discussed by kidney specialist Chiang Shou-shan.

Researchers from the University of Eastern Finland studied 51 adults with an average age of about 50. Participants spent 30 minutes in a sauna and briefly took a cold shower halfway through the session to cool down.

After the sauna, the participants had higher levels of several types of circulating white blood cells, including neutrophils and lymphocytes. These cells play important roles in the immune system and help the body respond to infections. Their levels returned to normal within about 30 minutes after the sauna ended.

The researchers suggested that sauna heat may move more white blood cells from tissues into the bloodstream before the cells return to those tissues. The temporary circulation of these cells could improve immune surveillance and help the body react to potential threats. Similar white blood cell release can also occur during exercise, the researchers said.

The findings appeared in the scientific journal Temperature. Chiang also cited earlier research tracking people for more than 20 years that linked frequent hot bathing with longer life and lower all-cause, cancer and cardiovascular mortality. He warned, however, that people who received a heart stent within the previous two months or underwent heart surgery within three months should not use hot baths.