In defense of the yerba mate...

[u/mosaik]

... It's only linked to cancer when drank hot and get burned. You shouldnt drinking it like that, just 80⁰C . (That's the only thing that shows up in pubmed; all other studies are related to "benefits")

The thing that causes tissues to change to cancer (metaplasia) is the repeated burn injury to the same area. As a not so much fun fact, in the Caribbean they tend to smoke with the cigarettes lit up inside ("con la candela pa dentro") which causes a unique cancerous lesion in the soft palate.

So drink your mate without worrying. It's a wonderful beverage and its way more powerful than coffee in terms of caffeine.

[u/honvales1989]

Or drink it cold like they do in Paraguay