Randomized controlled trials — molecular hydrogen water
Level 2 — Randomized Controlled Trials

Level 2 — Randomized Controlled Trials

RCTs — the gold standard in medicine. Patients randomized, H₂ in one group, placebo in the other. The difference is measured.

Applied evidence, organized by body system.

The 54 articles in this level are that kind of experiment, organized by body system. Here is the heart of the directory.

Start with the strongest

The studies in this section

54 studies
Aging: Longer Telomeres in 6 Months 07
Level 2 · RCT

Aging: Longer Telomeres in 6 Months

DOI · 10.1016/j.exger.2021.111574
Type 2 Diabetes: Glucose Normalized — Kajiyama 2008 08
Level 2 · Double-blind RCT

Type 2 Diabetes: Glucose Normalized — Kajiyama 2008

DOI · https://pubmed.ncbi.nlm.nih.gov/19083400/
Type 2 Diabetes: Higher Resistance, Bigger Response 09
Level 2 · Double-blind RCT

Type 2 Diabetes: Higher Resistance, Bigger Response

DOI · 10.1007/s13340-021-00524-3
Endothelial Function: H₂ Water at 7 ppm Restores Vascular Dilation in 4 Weeks 10
Level 2 · RCT

Endothelial Function: H₂ Water at 7 ppm Restores Vascular Dilation in 4 Weeks

DOI · 10.1371/journal.pone.0233484
H₂ Concentration Matters: Vascular Gains Only Above 3.5 mg/L 11
Level 2 · Clinical

H₂ Concentration Matters: Vascular Gains Only Above 3.5 mg/L

DOI · 10.2147/VHRM.S68844
Metabolic Syndrome: LDL Down, HDL Up — Song 2013 12
Level 2 · Double-blind RCT

Metabolic Syndrome: LDL Down, HDL Up — Song 2013

DOI · 10.1194/jlr.M036640
Metabolic Syndrome: Antioxidant Defenses Restored 13
Level 2 · Clinical

Metabolic Syndrome: Antioxidant Defenses Restored

DOI · 10.3164/jcbn.09-100
H₂ Water Cuts Body Fat and Improves Metabolism in 4 Weeks 14
Level 2 · RCT

H₂ Water Cuts Body Fat and Improves Metabolism in 4 Weeks

DOI · 10.1007/s11845-017-1638-4
Resting Metabolism Lifted in Women on H₂ Water 15
Level 2 · RCT

Resting Metabolism Lifted in Women on H₂ Water

DOI · 10.4103/mgr.MEDGASRES-D-24-00085
Heart Attack: Inhaled H₂ Protects the Myocardium — Katsumata 2017 16
Level 2 · Pilot

Heart Attack: Inhaled H₂ Protects the Myocardium — Katsumata 2017

DOI · https://pubmed.ncbi.nlm.nih.gov/28321000/
HYBRID II Protocol: H₂ for Neurological Recovery After Cardiac Arrest 17
Level 2 · RCT

HYBRID II Protocol: H₂ for Neurological Recovery After Cardiac Arrest

DOI · 10.1186/s13063-017-2246-3
H₂ + Magnesium for Severe Subarachnoid Hemorrhage: Neuroprotection Protocol 18
Level 2 · RCT

H₂ + Magnesium for Severe Subarachnoid Hemorrhage: Neuroprotection Protocol

DOI · 10.1186/s12883-014-0176-1
Memory Slipping? Molecular Hydrogen Reverses Mild Cognitive Impairment in 12 Weeks 19
Level 2 · Double-blind RCT

Memory Slipping? Molecular Hydrogen Reverses Mild Cognitive Impairment in 12 Weeks

DOI · https://pubmed.ncbi.nlm.nih.gov/29110615/
Memory + Fatigue: H₂ + PQQ Reverses Cognitive Decline in Older Adults in 6 Weeks 20
Level 2 · RCT

Memory + Fatigue: H₂ + PQQ Reverses Cognitive Decline in Older Adults in 6 Weeks

DOI · 10.1016/j.jnha.2024.100287
Early Parkinson's: Molecular Hydrogen Slows Documented Dopamine Loss 21
Level 2 · Double-blind RCT

Early Parkinson's: Molecular Hydrogen Slows Documented Dopamine Loss

DOI · 10.1002/mds.25375
Chronic Anxiety: Molecular Hydrogen Balances the Vagal Nerve Without a Drug 22
Level 2 · RCT

Chronic Anxiety: Molecular Hydrogen Balances the Vagal Nerve Without a Drug

DOI · 10.4103/2045-9912.222448
Acute Ischemic Stroke: Inhaled H₂ Gas Protects Neurons in the First 24 Hours 23
Level 2 · RCT

Acute Ischemic Stroke: Inhaled H₂ Gas Protects Neurons in the First 24 Hours

DOI · 10.1016/j.jstrokecerebrovasdis.2017.06.012
Fatty Liver: How H₂ Reduces Fat Accumulation 24
Level 2 · Clinical

Fatty Liver: How H₂ Reduces Fat Accumulation

DOI · 10.1016/j.clinre.2019.03.008
Fatty Liver: 8 Weeks of H₂ Water Switches Off Inflammation 25
Level 2 · Double-blind RCT

Fatty Liver: 8 Weeks of H₂ Water Switches Off Inflammation

DOI · 10.3390/antiox11101935
Hepatitis B: Liver Enzymes Restored on H₂ Water 26
Level 2 · RCT

Hepatitis B: Liver Enzymes Restored on H₂ Water

DOI · https://pubmed.ncbi.nlm.nih.gov/24127924/
Long-COVID: 14 Days, Less Fatigue 27
Level 2 · RCT

Long-COVID: 14 Days, Less Fatigue

DOI · 10.3390/nu16101529
Post-COVID-19: Molecular Hydrogen Improves Physical and Respiratory Function 28
Level 2 · Clinical

Post-COVID-19: Molecular Hydrogen Improves Physical and Respiratory Function

DOI · 10.3390/ijerph19041992
Post-COVID Syndrome: H₂ + Inhaled Nitric Oxide Improves Outcomes 29
Level 2 · Clinical

Post-COVID Syndrome: H₂ + Inhaled Nitric Oxide Improves Outcomes

DOI · 10.26442/00403660.2026.03.203537
Rheumatoid Arthritis: IV Hydrogen Lowers Inflammatory Activity 30
Level 2 · Double-blind RCT

Rheumatoid Arthritis: IV Hydrogen Lowers Inflammatory Activity

DOI · https://pubmed.ncbi.nlm.nih.gov/24929023/
H₂ Water in Rheumatoid Arthritis: Oxidative Stress and DAS28 Down 31
Level 2 · RCT

H₂ Water in Rheumatoid Arthritis: Oxidative Stress and DAS28 Down

DOI · 10.1186/2045-9912-2-27
Psoriasis: How H₂ Reduces PASI and Visible Symptoms 32
Level 2 · Clinical

Psoriasis: How H₂ Reduces PASI and Visible Symptoms

DOI · 10.1038/s41598-018-26388-3
Periodontitis: How H₂ Accelerates Gum Recovery 33
Level 2 · Clinical

Periodontitis: How H₂ Accelerates Gum Recovery

DOI · https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712607/
Hemodialysis: How H₂ Reduces Cardiovascular Mortality 34
Level 2 · Clinical

Hemodialysis: How H₂ Reduces Cardiovascular Mortality

DOI · 10.1038/s41598-017-18537-x
Hemodialysis: Red Blood Cell Protection — Huang 2006 35
Level 2 · RCT

Hemodialysis: Red Blood Cell Protection — Huang 2006

DOI · 10.1038/sj.ki.5001576
H₂ Water in Kidney Disease: The Foundational 2003 Study — Huang 36
Level 2 · Foundational RCT

H₂ Water in Kidney Disease: The Foundational 2003 Study — Huang

DOI · 10.1046/j.1523-1755.2003.00118.x
Radiotherapy for Liver Cancer: H₂ Water Improves Quality of Life Without Interfering 37
Level 2 · RCT

Radiotherapy for Liver Cancer: H₂ Water Improves Quality of Life Without Interfering

DOI · https://pubmed.ncbi.nlm.nih.gov/22146004/
Molecular Hydrogen in Mitochondrial Myopathies: Mitochondrial Function Restored (2011 RCT) 38
Level 2 · Double-blind RCT

Molecular Hydrogen in Mitochondrial Myopathies: Mitochondrial Function Restored (2011 RCT)

DOI · 10.1186/2045-9912-1-24
Interstitial Cystitis: Bladder Pain Reduced on H₂ Water — Matsumoto 2013 39
Level 2 · Clinical

Interstitial Cystitis: Bladder Pain Reduced on H₂ Water — Matsumoto 2013

DOI · https://pubmed.ncbi.nlm.nih.gov/23374763/
Postoperative Red Blood Cells Protected by Molecular Hydrogen (RCT) 40
Level 2 · RCT

Postoperative Red Blood Cells Protected by Molecular Hydrogen (RCT)

DOI · 10.4103/2045-9912.356473
Hydrogen Inhalation Lowers Circulating Free Radicals — Free Radical Biology 2024 41
Level 2 · RCT

Hydrogen Inhalation Lowers Circulating Free Radicals — Free Radical Biology 2024

DOI · 10.1016/j.freeradbiomed.2024.07.010
First Double-Blind Trial of Ionized Water for Diarrhea (1998) 42
Level 2 · Historic RCT

First Double-Blind Trial of Ionized Water for Diarrhea (1998)

DOI · 10.1016/j.tifs.2011.10.009
H₂ Water Reduces Premenstrual Symptoms: 2024 RCT 43
Level 2 · RCT

H₂ Water Reduces Premenstrual Symptoms: 2024 RCT

DOI · 10.1186/s12905-024-03029-8
Shortness of Breath: More Efficient Breathing on H₂ Water 44
Level 2 · Double-blind RCT

Shortness of Breath: More Efficient Breathing on H₂ Water

DOI · 10.1055/a-0991-0268
Soreness: 1260 mL Cuts DOMS at 24 Hours 45
Level 2 · Double-blind RCT

Soreness: 1260 mL Cuts DOMS at 24 Hours

DOI · 10.1519/JSC.0000000000003979
Athletic Fatigue: 500 mL Pre-Effort 46
Level 2 · Double-blind RCT

Athletic Fatigue: 500 mL Pre-Effort

DOI · 10.3389/fphys.2023.1240871
Post-Exercise Fatigue: H₂ Water Improves Endurance and Cuts Psychometric Fatigue 47
Level 2 · Double-blind RCT

Post-Exercise Fatigue: H₂ Water Improves Endurance and Cuts Psychometric Fatigue

DOI · 10.1139/cjpp-2019-0059
Hard Exercise: Molecular Hydrogen Optimizes Breathing and Muscle Oxygenation 48
Level 2 · Clinical

Hard Exercise: Molecular Hydrogen Optimizes Breathing and Muscle Oxygenation

DOI · 10.3390/nu13020459
Post-Exercise Recovery: Inhaled H₂ Reduces Muscle Damage and Improves the Next Session 49
Level 2 · Clinical

Post-Exercise Recovery: Inhaled H₂ Reduces Muscle Damage and Improves the Next Session

DOI · 10.4103/2045-9912.304222
High-Intensity HIIT: A Single Dose of H₂ Modulates Physiology Under Maximal Effort 50
Level 2 · Clinical

High-Intensity HIIT: A Single Dose of H₂ Modulates Physiology Under Maximal Effort

DOI · 10.3390/nu14193974
H₂ Inhalation: What Happened with SpO₂ (2026 Study) 51
Level 2 · Double-blind RCT

H₂ Inhalation: What Happened with SpO₂ (2026 Study)

DOI · 10.1139/cjpp-2025-0228
Molecular Hydrogen and Lactate: A Study in Soccer Players 52
Level 2 · Double-blind RCT

Molecular Hydrogen and Lactate: A Study in Soccer Players

DOI · 10.1186/2045-9912-2-12
Molecular Hydrogen Sustains Repeated-Sprint Performance: Soccer Study (2022) 53
Level 2 · Double-blind RCT

Molecular Hydrogen Sustains Repeated-Sprint Performance: Soccer Study (2022)

DOI · 10.3390/nu14030508
2 Weeks of H₂ Water Raise VO₂ Max in Cyclists (2020 RCT) 54
Level 2 · RCT

2 Weeks of H₂ Water Raise VO₂ Max in Cyclists (2020 RCT)

DOI · 10.4103/2045-9912.304223
Blood pH and H₂: Higher Alkalinity in Athletes 55
Level 2 · RCT

Blood pH and H₂: Higher Alkalinity in Athletes

DOI · 10.1080/15438627.2013.852092
Negative ORP and Performance: H₂ Improves Exercise Output 56
Level 2 · Double-blind RCT

Negative ORP and Performance: H₂ Improves Exercise Output

DOI · https://www.researchgate.net/publication/225183451
Hydrogen Baths: DOMS and Oxidative Stress Down 57
Level 2 · RCT

Hydrogen Baths: DOMS and Oxidative Stress Down

DOI · 10.7600/jspfsm.65.297
Soft-Tissue Injuries: Oral + Topical H₂ Speeds Recovery 58
Level 2 · Double-blind RCT

Soft-Tissue Injuries: Oral + Topical H₂ Speeds Recovery

DOI · 10.3810/pgm.2014.09.2813
Hydrotherapy vs RICE for Ankle Sprain: Equally Fast Recovery 59
Level 2 · RCT

Hydrotherapy vs RICE for Ankle Sprain: Equally Fast Recovery

DOI · 10.1080/15438627.2020.1868468
Double Session: Recovery in Elite Swimmers 60
Level 2 · Double-blind RCT

Double Session: Recovery in Elite Swimmers

DOI · 10.3389/fphys.2024.1321160