This study compared the effects of hydrogen-water (HW) bath on the oxygen radical absorption-based antioxidant capacity and the inflammatory indicator, C-reactive protein (CRP), in serum between healthy volunteers and inflammatory/collagen disease-patients. The HW bath apparatus supplied nano-bubbles with a diameter of 110 ± 10 nm and 338-682 μg/L of dissolved hydrogen after 120 minutes electrolysis, and nano-bubbles increased to 9.91 × 107/mL along with the increase of correlative dissolved hydrogen. Ten-minute HW bath increased the oxygen radical absorption-based antioxidant capacity to 110.9 ± 9.2% at post-bathing 120 minutes, although unaltered with 10-minute normal water bath at 40°C in healthy subjects. The CRP level was repressed to 70.2 ± 12.1% at 120 minutes after HW bath, although rather increased for normal water bath. In the patients with connective tissue diseases, the CRP level was repressed to 3-24% upon 9 days to 4 months of HW bathing. In another six patients with diverse autoimmune-related diseases, upon daily HW bathing as long as 2-25 months, the pre-bathing CRP level of 5.31 mg/dL decreased to 0.24 mg/dL being within the standard-range, with relief of visible inflammatory symptoms for some cases. Thus, the HW bath with high-density nano-bubbles has beneficial effects on serum antioxidant capacity, inflammation, and the skin appearance. The study was approved by the Committee of Ethics, Japanese Center of Anti-Aging Medical Sciences (Authorization No. H-15-03-2, on January 15, 2019), which was a non-profitable organization officially authenticated by the Hiroshima Prefecture Government of Japan.
Keywords: C-reactive protein; anti-inflammatory effect; antioxidant capacity; electrolysis; human serum; human skin; hydrogen-rich water; nano-bubble.