Does methylene blue really have wellness benefits or will it just leave you with the blues? | Antiviral

The fabric dye is popular in wellness circles, with a laundry list of claimed benefits – but it also carries serious risks

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A week before he was sworn in as secretary of the US Department of Health and Human Services in February, a video of anti-vaccination conspiracy theorist Robert F Kennedy Jr went viral.

In it, Kennedy, who has frequently promoted debunked health claims, is seen squirting inky blue liquid into a drinking glass. The substance was widely speculated to be a dye called methylene blue, though Kennedy has not publicly commented on it.