20/08/2026
MILD HYPERBARIC OXYGEN + THE IMMUNE SYSTEM 🫁🧬
What happens inside the body after just one mild hyperbaric oxygen session?
This study investigated 16 healthy young women following a 70-minute exposure to mild hyperbaric oxygen at 1.4 ATA with 35–40% oxygen, compared with a normal-pressure control condition.
The researchers found two particularly interesting changes:
🧠 Parasympathetic activity increased
High-frequency heart rate variability (HF-HRV) increased following mild hyperbaric oxygen exposure, suggesting increased parasympathetic nervous system activity.
🧬 Circulating Natural Killer (NK) cells increased
NK-cell numbers increased from approximately 2.28 to 4.44 cells/μL, with the change significantly greater than the control condition.
Natural Killer cells are part of our innate immune system and play an important role in identifying and responding to abnormal or infected cells.
Interestingly, researchers did not find a significant increase in the NK-cell activation marker CD69, or significant changes in the measured oxidative stress and inflammatory markers.
So rather than simply saying “hyperbaric oxygen boosts immunity,” the findings are much more nuanced.
One exposure was associated with changes in autonomic nervous system activity and circulating immune-cell numbers — but this was a small study involving only 16 healthy young women and looked at the acute response to a single session.
More research is needed to understand what these changes mean clinically and whether they persist with repeated exposure.
Swipe through ➡️ to explore the study.
📖 Research:
Un Nisa B, Nakanishi R, Tanaka M, et al. Mild Hyperbaric Oxygen Exposure Enhances Peripheral Circulatory Natural Killer Cells in Healthy Young Women. Life. 2023;13(2):408.
NervousSystem HRV NaturalKillerCells ImmuneHealth HealthResearch EvidenceBasedPractice