Hydrogen Baths and Topical Use: Human Studies
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. 39 papers touch on this form, including 10 randomized controlled and 10 pilot and observational studies in humans, supplemented by preclinical investigations and reviews.
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.
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 39 studies using this route — 10 randomized trials, 10 pilot/observational studies and 8 reviews. Listed newest first.
Human studies (20)
2026 · Tsai et al. — Effects of Hydrogen Water Gargling on Oral Mucositis and Pain in Head and Neck Cancer Patients: A Randomized Controlled Pilot Study
In a randomised pilot trial in head and neck cancer patients receiving radiotherapy or chemoradiotherapy, the group gargling with hydrogen water showed significant improvement in oral mucositis at day 7 (p = 0.04) and day 14 (p = 0.002).
2024 · Jin et al. — Clinical Observation of Hydrogen-Rich Saline for Nasal Irrigation After Surgery for Chronic Sinusitis: A Randomized, Double-Blind, Controlled Trial
In 61 patients who had surgery for chronic rhinosinusitis, nasal irrigation with hydrogen-rich saline led to lower visual analogue scores after 12 weeks than normal saline (0.52 compared with 1.47, P=0.005).
2022 · Jin et al. — The Beneficial Effects of Hydrogen-Rich Saline Irrigation on Chronic Rhinitis: A Randomized, Double-Blind Clinical Trial
In 120 patients with chronic rhinitis, nasal irrigation with hydrogen-rich saline lowered the total nasal symptom score more than irrigation with normal saline, and the difference was statistically significant.
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.
2018 · Kawamura et al. — Involvement of Neutrophil Dynamics and Function in Exercise-Induced Muscle Damage and Delayed-Onset Muscle Soreness: Effect of Hydrogen Bath
In nine healthy young men, a daily hydrogen bath for one week after downhill running showed no effect on muscle soreness, neutrophil counts and function, muscle damage or inflammation markers compared with a placebo bath.
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.
2025 · Debkowska et al. — Topically Applied Molecular Hydrogen Normalizes Skin Parameters Associated with Oxidative Stress: A Pilot Study
In 15 healthy adults, four weeks of topical treatments with hydrogen-rich water were followed by a statistically significant reduction in pore visibility, while the reduction in porphyrin levels was not statistically significant.
2025 · Devi et al. — Hydrogen Water Versus Normal Saline for Post-Surgical Irrigation: A Study on Healing and Complication Rates After Third Molar Extraction
In 30 patients having impacted lower wisdom teeth removed, irrigating the surgical site with hydrogen water instead of normal saline was reported to give greater improvement in pain, swelling and restricted mouth opening and less dry socket from the second day after surgery.
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
2020 · Todorovic et al. — The Effects of Supersaturated Hydrogen-Rich Water Bathing on Biomarkers of Muscular Damage and Soreness Perception in Young Men Subjected to High-Intensity Eccentric Exercise
In six young men, a single 30-minute whole-body bath in water with 8 mg of hydrogen per litre after hard eccentric exercise kept serum creatine kinase similar to baseline at 24 hours, while it rose after a control bath (group difference P = 0.04).
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.
Reviews (8)
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.
Preclinical (11)
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.