These people have been around forever but the pivotal point in my opinion is when the Lancet retracted the article on the link between MMR and autism.

Suddenly everything was up for debate.

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

You can’t be serious right now. Your teeth aren’t in your digestive tract.

> Your teeth aren’t in your digestive tract.

However:

Once ingested, the fluoride has a systemic affect on teeth before they erupt, incorporating into the matrix of developing teeth to increase the mineralization content and decrease the solubility of enamel. [1]

[1] https://www.uspharmacist.com/article/current-fluoride-recomm...