Bath / Topical
Bath / topical: H₂ delivered through the skin — via hydrogen-rich bathing water or local application. How much H₂ actually reaches the body this way is often unclear. Around 32 papers touch on this form, including about 6 randomized controlled and around 7 pilot and observational studies in humans, supplemented by preclinical investigations and reviews.</p><p>Skin and musculoskeletal topics are in the foreground: bathing in hydrogen-rich water or local applications were tested, for example, in skin complaints, wound healing and rheumatic complaints, often with a view to oxidative stress and inflammation.</p><p>A fundamental problem is the unclear systemic absorption through the skin, which complicates interpretation. Some studies report favorable local effects, but the data are small and heterogeneous — the evidence remains preliminary.
Human studies on molecular hydrogen given by Bath / Topical. This page collects the 32 studies using this route — 6 randomized trials, 7 pilot/observational studies and 8 reviews. Listed newest first.
2023 · Saengsin et al. — Hydrogen Therapy as a Potential Therapeutic Intervention in Heart Disease: From the Past Evidence to Future Application
This comprehensive review in Cellular and Molecular Life Sciences synthesises in-vitro, animal, and clinical evidence for molecular hydrogen's protective effects in cardiovascular disease, covering its antioxidant, anti-inflammatory, and anti-apoptotic mechanisms.
2021 · Quan — Protective effects of molecular hydrogen on lung injury from lung transplantation.
This review synthesizes the experimental evidence showing that H₂ — administered via inhalation, drinking, injection, or topical bath — can reduce the oxidative stress and inflammation responsible for primary graft dysfunction after lung transplantation.
2021 · Zhang et al. — Hydrogen Gas: A Novel Type of Antioxidant in Modulating Sexual Organs Homeostasis.
Molecular hydrogen (H₂) appears to benefit reproductive health in both males and females — from improving sperm motility and erectile function to protecting ovarian function and reducing uterine inflammation — acting primarily through antioxidant and anti-inflammatory mechanisms.
2020 · Kawamura et al. — Application of Molecular Hydrogen as a Novel Antioxidant in Sports Science
This review surveys the evidence on molecular hydrogen (H₂) intake and exercise, covering all administration routes and focusing on exercise-induced oxidative stress.
2015 · Ohta — Molecular hydrogen as a novel antioxidant: overview of the advantages of hydrogen for medical applications.
Molecular hydrogen (H₂) is a mild, selective antioxidant that neutralizes the most damaging reactive oxygen species without disrupting normal cellular redox signaling — a key advantage over broad-spectrum antioxidants.
2014 · Ohta — Molecular hydrogen as a preventive and therapeutic medical gas: initiation, development and potential of hydrogen medicine.
One of the founding papers of hydrogen medicine, authored by Shigeo Ohta, summarises how H₂ was discovered to react with harmful hydroxyl radicals in cells — and why this makes it a candidate for preventing and treating a wide range of diseases.
2012 · Ohta — Molecular hydrogen is a novel antioxidant to efficiently reduce oxidative stress with potential for the improvement of mitochondrial diseases.
This review by Shigeo Ohta — one of the founders of modern H₂ medicine — surveys the biological effects of molecular hydrogen across more than 38 diseases, physiological states, and clinical tests documented in the years following the 2007 Nature Medicine paper.
2011 · Ohta — Recent progress toward hydrogen medicine: potential of molecular hydrogen for preventive and therapeutic applications.
Since the landmark 2007 Nature Medicine paper demonstrating that molecular hydrogen (H₂) selectively neutralizes toxic hydroxyl radicals, the field of hydrogen medicine has grown rapidly.
2021 · Javorac — Hydrotherapy with hydrogen-rich water compared with RICE protocol following acute ankle sprain in professional athletes: a randomized non-inferiority pilot trial
Hydrogen-rich baths were just as effective as the gold-standard RICE procedure (rest, ice, compression, elevation) for acute ankle sprain in professional athletes.
2020 · Shibayama — Impact of hydrogen-rich gas mixture inhalation through nasal cannula during post-exercise recovery period on subsequent oxidative stress, muscle damage, and exercise performances in men
Inhaling hydrogen gas right after intense exercise lowered a DNA oxidation marker and protected jump strength from the exercise-induced drop. Other performance and blood markers, however, remained unchanged.
2020 · Jin — Changes of nasal nitric oxide in the treatment of allergic rhinitis with hydrogen-rich saline lavage of nasal cavity
A nasal lavage with hydrogen-rich saline significantly changed the nitric-oxide value in the nose and could thus offer a starting point for treating allergic rhinitis (hay fever).
2018 · Jin — Clinical Study of Hydrogen-Rich Saline in the Treatment of Moderate to Severe Allergic Rhinitis
Nasal lavage with hydrogen-rich saline significantly improved symptoms, signs, and quality of life in patients with moderate-to-severe allergic rhinitis — with no relevant adverse effects.
2014 · Ostojic et al. — Effectiveness of oral and topical hydrogen for sports-related soft tissue injuries.
In male professional athletes with acute soft tissue injuries, adding oral hydrogen tablets (2 g/day) plus topical hydrogen-rich packs accelerated joint range-of-motion recovery and reduced plasma viscosity compared to standard treatment alone.
2026 · Pozdnyakova — The combined use of inhaled nitric oxide and molecular hydrogen in patients with post-COVID-19 syndrome
Combined inhalation of nitric oxide (NO) and molecular hydrogen (H₂) relieves post-COVID syndrome better than NO alone.
2025 · Moriya et al. — Hydrogen Inhalation Is Associated With a Transient Rightward Shift in Prefrontal Oxyhemoglobin Asymmetry and Autonomic Modulation
A single 30-minute session of pure hydrogen gas inhalation (99.9 % H₂, 300 mL/min via nasal cannula) transiently increased oxygenation in the right prefrontal cortex and simultaneously altered heart-rate variability in healthy adults — findings consistent with a brief, coordinated neurovascular-autonomic response.
2022 · Tanaka — Hydrogen-rich bath with nano-sized bubbles improves antioxidant capacity and inflammation levels in human serum
A 10-minute bath in hydrogen-rich water with nano-bubbles raised blood antioxidant capacity by about 11% and lowered the inflammatory marker CRP by roughly 30% in healthy volunteers — and sustained CRP reductions were observed in patients with autoimmune conditions over months of daily bathing.
2021 · Kato — Heat-retention effects of hydrogen-rich water bath assessed by thermography for humans
2018 · Zhu — Positive Effects of Hydrogen-Water Bathing in Patients of Psoriasis and Parapsoriasis en Plaques
In a parallel-controlled trial, hydrogen-water bathing achieved at least 75% improvement in psoriasis severity (PASI-75) in 24.4% of patients versus 2.9% in controls, with over half the patients reaching PASI-50 improvement.
2025 · Zhu — Transdermal Hydrogen Therapy for Psoriasis Using Cavity-embedded Double-conical Microneedles
A new microneedle patch delivers hydrogen directly through the skin into psoriatic tissue, where sustained H₂ release significantly outperformed a standard topical therapy (calcipotriol cream) in reducing oxidative damage, inflammation, and the hallmark skin thickening of psoriasis.
2023 · Sahoo — Hydrogen-producing Photocatalyst at Sunscreen for Athletes in Preventing and Healing Muscle-nerve-skin Injuries
A theoretical concept paper proposes embedding a UV-absorbing photocatalyst into a hydrogel sunscreen that would continuously split sweat into H₂ — allowing athletes to absorb H₂ through the skin during sun exposure.
2022 · Chen et al. — Photocatalytic Glucose Depletion and Hydrogen Generation for Diabetic Wound Healing
Researchers engineered hydrogen-incorporated titanium oxide nanorods that, under visible light, simultaneously deplete glucose and generate molecular hydrogen (H₂) at diabetic wound sites — addressing both the hyperglycaemic microenvironment and chronic inflammation.
2022 · Yamamoto et al. — Development of a Model System for Gas Cavity Formation Behavior of Magnesium Alloy Implantation
This study developed an in-vitro gelatin model to simulate and measure the hydrogen gas cavities that form in tissue when biodegradable magnesium (Mg) bone screws corrode — a known clinical challenge in orthopaedic surgery.
2021 · Hartjen — Toward Tailoring the Degradation Rate of Magnesium-Based Biomaterials for Various Medical Applications: Assessing Corrosion, Cytocompatibility and Immunological Effects
This in-vitro materials science study tested a surface-treated magnesium alloy (WE43 with plasma electrolytic oxidation) as a degradable implant material.
2019 · Meng — Hyperoxygenated Hydrogen-Rich Solution Suppresses Lung Injury Induced by Hemorrhagic Shock in Rats.
In rats with hemorrhagic-shock-induced acute lung injury (ALI), intravenous infusion of a solution combining both extra oxygen and dissolved hydrogen (HOHS) outperformed standard resuscitation fluid and each component alone in protecting lung tissue.
2017 · Zhao — Changes in IL-4 and IL-13 Expression in Allergic Rhinitis Treated with Hydrogen-Rich Saline in a Guinea-Pig Model
Hydrogen-rich saline significantly reduced sneezing, scratching, IgE levels, and key allergy-driving cytokines (IL-4, IL-13) in guinea pigs with experimentally induced allergic rhinitis.
2014 · Chen — Controlling initial biodegradation of magnesium by a biocompatible strontium phosphate conversion coating
Magnesium implants dissolve too quickly after implantation — a strontium phosphate (SrP) coating developed in this in-vitro study significantly slows this degradation.
2012 · Baxter et al. — Evaluation of outgassing, tear strength, and detail reproduction in alginate substitute materials.
This study compares dental impression materials (alginate substitutes) to traditional alginate for three performance properties: the release of hydrogen gas (outgassing), tear strength, and detail reproduction quality.
2012 · Kato et al. — Hydrogen-rich electrolyzed warm water represses wrinkle formation against UVA ray together with type-I collagen production and oxidative-stress diminishment in fibroblasts and cell-injury prevention in keratinocytes.
UVA radiation from sunlight damages skin cells, promotes wrinkle formation, and reduces collagen production — primarily via oxidative stress from reactive oxygen species.
2011 · Gao — Fabrication and Characterization of Bioactive Composite Coatings on Mg-Zn-Ca Alloy by MAO/Sol-Gel
This in-vitro materials science study develops a two-layer protective coating for magnesium alloy implants that dramatically reduces corrosion and supports cell adhesion — addressing one of the main obstacles to using biodegradable magnesium in medical implants, namely the rapid release of hydrogen gas during degradation.