81 clinical trials have tested hydrogen water. Here's what the research actually shows — the wins, the gaps, and what still needs more study.

Most hydrogen water bottles don't publish the one number that matters: ppm output. The minimum effective dose is 0.5 ppm, and budget bottles rarely reach it. This guide covers exactly what specs to verify, why PEM electrolysis beats chemical-reaction bottles, and when a home ionizer outperforms any portable option.