Can Hydrogen Water Help Parkinson's Disease? What the Largest Trial Found

An earlier, smaller pilot study on hydrogen water and Parkinson's disease looked promising. This much larger follow-up trial was designed to confirm it — and it didn't. We think that result belongs in this library just as much as a positive one.

What the research looked at

Published in Movement Disorders in 2018, this randomized, double-blind, multicenter trial enrolled 178 patients with Parkinson's disease across 14 hospitals in Japan, most of whom were also being treated with levodopa. Participants were randomly assigned to drink one liter per day of hydrogen water or a placebo water for up to 72 weeks. Researchers tracked disease severity using the Unified Parkinson's Disease Rating Scale (UPDRS), along with quality-of-life and disease-stage measures.

What they found

After 72 weeks, there was no statistically significant difference between the hydrogen water group and the placebo group on total UPDRS score, any of its individual components, quality-of-life scores, or disease stage. The trial did not replicate the encouraging results seen in an earlier, smaller pilot study.

What this means in practice

This is exactly the kind of study that should carry real weight — large, randomized, double-blind, and multicenter, run specifically to confirm an earlier promising result. It didn't. That doesn't necessarily mean hydrogen water has zero biological effect (the mechanism research on oxidative stress is real), but it does mean there's currently no solid evidence it changes the course of Parkinson's disease, and it shouldn't be used as a substitute for standard treatment. We'd rather tell you this plainly than only cite the smaller, earlier study that pointed the other way.