One study of 49 people with liver cancer showed that drinking hydrogen-rich water for six weeks during radiation therapy could improve quality of life during treatment.
Side effects of radiation therapy include:
Fatigue
Hair loss
Skin problems
Nausea
Headaches
Soreness in the area treated
The study showed that quality of life scores were higher in the group that drank hydrogen water, versus the placebo group consuming regular water. But further study is needed.