A recent study conducted in Japan reveals that hydrogen-water (HW) baths may significantly boost antioxidant levels and reduce inflammation, offering potential health benefits for both healthy individuals and patients with autoimmune or collagen-related diseases.

The research evaluated the effects of HW baths on antioxidant activity—specifically oxygen radical absorption—and the inflammatory marker C-reactive protein (CRP). Using a specialized bath system that produces nano-sized hydrogen bubbles (around 110 nanometers) and dissolves up to 682 µg/L of hydrogen through a 120-minute electrolysis process, researchers observed a marked improvement in participants’ health markers.

In healthy volunteers, a 10-minute soak in HW raised antioxidant capacity by over 10% after two hours, a benefit not seen with normal 40°C water. Additionally, CRP levels—a key indicator of inflammation—dropped by nearly 30% after an HW bath, whereas they slightly increased following a regular bath.

Even more striking results were reported among patients with inflammatory and autoimmune conditions. Those with connective tissue diseases experienced a reduction in CRP levels by up to 97% after using HW baths consistently for 9 days to 4 months. In another group of autoimmune patients, daily HW baths over periods ranging from 2 to 25 months reduced CRP from an average of 5.31 mg/dL to just 0.24 mg/dL, bringing inflammation within the normal range and visibly easing symptoms in some cases.

The findings suggest that regular HW bathing, enriched with nano-hydrogen bubbles, may offer a natural way to support the body’s antioxidant defenses and manage chronic inflammation. The study was officially approved by the Committee of Ethics at the Japanese Center of Anti-Aging Medical Sciences and recognized by the Hiroshima Prefecture Government.