水素吸入が血中活性酸素種レベルに与える影響：無作為化対照試験
Reactive oxygen species (ROS) participate in normal physiological functions, yet an excess relative to antioxidant capacity leads to oxidative stress implicated in various pathological conditions. Molecular hydrogen possesses selective antioxidant properties and high membrane permeability, making it a candidate for reducing oxidative burden. This randomized controlled trial enrolled 37 individuals with elevated blood ROS levels (d-ROMs > 350 U.CARR) and assigned them to either a hydrogen inhalation group or a non-intervention control group. Blood ROS concentrations were assessed immediately after the intervention and again at 24 hours. The hydrogen inhalation group exhibited a statistically significant decrease in circulating ROS compared with controls, supporting the capacity of hydrogen gas inhalation to reduce systemic oxidative stress markers.
Molecular hydrogen, owing to its small molecular size and selective reactivity, is thought to neutralize excess reactive oxygen species without disrupting normal redox signaling, thereby lowering circulating oxidative stress markers.
For inhalation applications of molecular hydrogen, the lower flammability limit (LFL) deserves careful handling. The classical 4% figure applies to closed-system mixtures; the practical inhalation-environment threshold is 10%. Even pure-hydrogen output (the UFL 75% paradox) passes through the flammable range at the air–gas boundary. High-concentration (66% / 100%) inhalers are documented in the Japanese Consumer Affairs Agency accident-information database and are not recommended.
See also:
https://h2-papers.org/en/papers/38996821