Ok, it turns out that my skeptic alarm wasn't wrong on this. It looks like there's a whole cottage industry of people who are peddling non-FDA-approved UV blood irradiation therapy and ozone therapy as a cure-all for everything from depression to AIDS. It goes by the name "BioPhotonic Therapy" if you do some googling. There's probably a good reason why nobody besides "alternative medicine" providers practice this stuff [1].

[1] https://health.wusf.usf.edu/post/despite-skeptics-alternativ...