A single 15-minute Finnish sauna session at 96°F can increase white blood cell profiles and beneficially adjust cortisol levels for combating infection.

“after the first and 10th Saab baths they witnessed an increase in lucite count lucaites are a particular type of cell of the inate immune system however only after the last sauna session did this change reach statistical significance in the trained group”

“Sauna use does increase immune cell numbers and is associated with reduced incidence of respiratory diseases.”

“A single 30-minute session at ~165°F (enough to elevate body temperature to 101°F) increased levels of several immune cells including lymphocytes and neutrophils for up to 30 minutes.”

“This occurred in non-users and people who used sauna 2-3 times per week more.”

“the mechanism by which frequency on use reduces the incidence of colds is unknown but it could have to do with the modulation of the immune system white blood cells lymphocytes and neutrophil counts were all increased in both trained and non trained athletes after sauna use”