Overview
- In a paper in the journal Temperature, Finnish researchers measured blood before and after a 30-minute sauna with a quick cold rinse and saw higher white blood cell counts.
- Neutrophils and lymphocytes rose during the session and returned to baseline within about 30 minutes afterward.
- Average cytokine levels changed little, but several cytokines varied in step with how much a participant’s body temperature increased.
- The study tested 51 adults with a mean age of 50 and examined only the immediate effects of a single visit.
- The authors interpret the rise as short-term mobilization of immune cells, similar to exercise, and they caution it does not prove lasting health benefits.