Programs that do multiple things are not simple, so successfully using or understanding what they do is less likely to be possible for you. I expect that wanting to avoid interacting with many programs will lead a person to use programs that are nonfree more often than they otherwise would, so it would be more likely that a program controls the users.
I think this is not among the most important things to be talking about.
https://www.hsph.harvard.edu/magazine/magazine_article/fluoridated-drinking-water/
https://nutritionsource.hsph.harvard.edu/fluoride/
https://duckduckgo.com/?t=ftsa&q=fluoride+site%3A.edu&ia=web