Repetitive Bathing and Skin Poultice with Hydrogen-Rich Water Improve Wrinkles and Blotches Together with Modulation of Skin Oiliness and Moisture

Abstract

Hydrogen-rich warm water (HW) has not been verified yet for skin anti-aging effects. Daily 10 min HW (dissolved hydrogen: 338–682 μg/mL, 41 °C) bathing and skin poultice with HW-impregnated towels for 11–98 days were demonstrated to improve wrinkle degrees (29 skin-loci) from 3.14 ± 0.52 to 1.52 ± 0.74 (p < 0.001) and blotch degrees (23 loci) from 3.48 ± 0.67 to 1.74 ± 0.92 (p < 0.001) in five healthy subjects (49–66 years old), by densito-/planimetrically evaluating with an Image-J software, and ranking into six hierarchies (0, 1–5). Meanwhile, skin oiliness was evaluated to increase for the oil-poor skins, but inversely decrease for excessively oily skins, suggesting the HW’s function as skin-oiliness modulation, with an appreciably negative correlation in prior oiliness contents versus change after HW application (r = −0.345, 23 loci). Skin moisture increased upon HW application, with a negative correlation (r = −0.090, 23 loci) in prior moisture contents versus post-HW-application moisture-changing rates, meaning that HW application compensated moisture for water-deficient skins (27.5–40% moisture), but not for wet skins (>41% moisture). Thus, the HW bath together with HW poultice exerted beneficial effects on skin appearances such as wrinkles, blotches and moisture/oiliness, some of which might ensue from enhanced antioxidant ability in blood, as was previously demonstrated for the HW bath.