STUDY: Single 30-Minute Sauna Session Elevates Immune Cell Levels in Bloodstream

Published April 15, 2026

Researchers from Finland discovered that a single 30-minute sauna session at a temperature of 163 degrees Fahrenheit led to a notable increase in immune cells circulating in the blood of participants.

The investigation involved monitoring 51 healthy adults at multiple points: before, during, and after engaging in traditional sauna bathing. Results showed that white blood cell counts rose immediately following the sauna exposure. Specifically, neutrophils and lymphocytes surged but then returned to baseline within 30 minutes post-session.

Both frequent sauna users and those who used saunas occasionally exhibited the same immune response, suggesting that the immune-boosting effect remains consistent regardless of sauna use frequency.

This study contributes to the growing body of evidence supporting sauna bathing, highlighting immune system benefits alongside the already well-established cardiovascular health improvements.