Pharmacokinetics of hydrogen after ingesting a hydrogen-rich solution: A study in pigs

Drinking hydrogen (H₂)-rich water is a common way to consume H₂. Although many studies have shown efficacy of drinking H₂-rich water in neuropsychiatric and endocrine metabolic disorders, their authenticity has been questioned because none examined the associated pharmacokinetics of H₂. Therefore, we performed the first study to investigate the pharmacokinetics of H₂ in pigs given an H₂-rich glucose solution with the aim to extrapolate the findings to humans. We inserted blood collection catheters into the jejunal and portal veins, suprahepatic inferior vena cava, and carotid artery of 4 female pigs aged 8 weeks. Then, within 2 min we infused 500 ml of either H₂-rich or H₂-free glucose solution into the jejunum via a percutaneous gastrostomy tube and measured changes in H₂ concentration in venous and arterial blood over 120 min. After infusion of the H₂-rich glucose solution, H₂ concentration in the portal vein peaked at 0.05 mg/L and remained at more than 0.016 mg/L (H₂ saturation level, 1%) after 1 h; it also increased after infusion of H₂-free glucose solution but remained below 0.001 mg/L (H₂ saturation level, 0.06%). We assume that H₂ was subsequently metabolized in the liver or eliminated via the lungs because it was not detected in the carotid artery. In conclusion, drinking highly concentrated H₂-rich solution within a short time is a good way to increase H₂ concentration in portal blood and supply H₂ to the liver.