Molecular hydrogen is an intriguing option for metabolic conditions which are often associated with high levels of oxidative stress and inflammation. While some trials have pointed to potential benefits, the research is mixed, and all outcomes require replication in further trials.
Hydrogen-rich water (HRW) might improve lipid profiles, more specifically by reducing LDL cholesterol, total cholesterol, and triglycerides. However, the effects appear small or marginally beneficial.[1]
A randomized controlled trial in people with metabolic syndrome reported that HRW reduced oxidative stress biomarkers, improved lipid profiles, and reduced fasting glucose and HbA1c after 24 weeks.[2] The participants consumed 750 mL (0.75 L) of HRW (7.3 millimolar (mM)) daily. Studies providing HRW at lower concentrations and for shorter durations have not found these benefits, aside from reduced oxidative stress biomarkers.[3][4]
In nonalcoholic fatty liver disease (NAFLD), a small trial reported that 1 L (1,000 mL) of HRW (3 mM) daily for 28 days reduced liver fat accumulation compared to a placebo.[5] In another trial, hydrogen gas (66% hydrogen and 33% oxygen) inhaled for 1 hour daily for 13 weeks was reported to reduce liver enzymes, inflammatory markers, and oxidative stress biomarkers compared to baseline, with no changes observed in the control group.[6]