Fluoride can be bad for you, just at much higher doses than they put in water supply. It can cause issues with bones and neurological development. Again, only in very high doses over a long time. It happens a lot in poorer countries where they can’t treat well water.

https://en.m.wikipedia.org/wiki/Skeletal_fluorosis

I just made the jump to Ubuntu. You don’t need a Steam Deck or Steam OS. Steam works just as well on any Linux OS. Proton is the real star because it deals with the compatibility issues so well.

I just set up an Ubuntu dual boot last week. Valve has really made Linux gaming easy. Just one checkbox to enable Steamplay. I don’t see myself going back to Windows any time soon. Good luck with Mint.