In Rio during the 2016 Summer Olympics, water in two of the swimming pools mysteriously turned a murky green color.

At a press conference a few days later, officials explained that cleaning personnel had dumped 42-plus gallons of hydrogen peroxide into the pools, most likely disabling the effect of chlorine already in the water and making it a hospitable environment for organic compounds, including blooming algae.

This is just one example of what happens if you misuse hydrogen peroxide. You can see examples of it all over the internet, where advocates would like you to believe that drinking a “food-grade,” highly concentrated 35-percent hydrogen peroxide solution is an effective treatment for all that ails you, including cancer, allergies and Alzheimer’s disease.

The Food and Drug Administration has cautioned that these fake cures come with potentially devastating side effects. One study in the Annals of Emergency Medicine looked at 294 people who ingested high-concentration hydrogen peroxide and found they suffered serious health risks, including blood clots, long-term disability and death.

Even the hydrogen peroxide you can buy at drugstores — it’s just a 3-percent concentration — can irritate your eyes, throat, airway, skin and gastrointestinal system.

Research shows it doesn’t do much to heal wounds and actually may delay wound healing. While the bubbling that occurs on the surface when you dab an injury with it does indicate it’s killing bacteria, it’s also damaging healthy skin cells. Instead, use saline or plain old water; they’re just as effective and perhaps more beneficial to a skin injury.

Mehmet Oz, M.D., is host of “The Dr. Oz Show,” and Mike Roizen, M.D., is Chief Wellness Officer and Chair of Wellness Institute at Cleveland Clinic. Email questions to youdocsdaily@sharecare.com.