There is emerging scientific interest in the use of molecular hydrogen (H₂) as a potential adjunctive therapy for autoimmune disorders, though the evidence is still preliminary and mainly based on animal studies and limited human trials. Molecular hydrogen acts as a selective antioxidant, specifically neutralizing hydroxyl radicals and peroxynitrite, which are highly reactive oxygen species implicated in inflammation and tissue damage. Several preclinical studies suggest that hydrogen-rich water or hydrogen gas inhalation can modulate immune responses and decrease inflammatory cytokines in animal models of autoimmune diseases such as rheumatoid arthritis and multiple sclerosis.

Additionally, a few small-scale human studies and case reports have observed improvements in clinical symptoms and biomarkers of inflammation when hydrogen was administered, typically as hydrogen-rich water. However, these studies often have small sample sizes, short durations, and lack rigorous controls. No large-scale, high-quality randomized controlled trials have conclusively demonstrated efficacy or established hydrogen therapy as a standard treatment for autoimmune disorders. As such, while there is a scientific rationale and some encouraging early data, the overall quality and quantity of evidence remain low, and hydrogen therapy should not replace established treatments. Further research is needed to confirm safety, efficacy, and optimal dosing strategies in humans.