[newZWhoDis]

The link you mention is from the mouth bacteria/plaques and their leakage into the blood stream near the brain.

Fluoride is not an antibiotic, so there is no plausible mechanism for it’s known topical benefits to prevent bacterial growth that might lead to Alzheimer’s (itself a theory, but an interesting one)

[napier]

Municipal water fluoridation is problematic for a range of reasons but as a toothpaste and mouthwash it has merit and it actually does demonstrate direct bacterial growth arrest effects in addition to indirect substrate permissiveness inhibition via mineralisation.

“Fluoride acts to enhance membrane permeabilities to protons and compromises the functioning of F-ATPases in exporting protons, thereby inducing cytoplasmic acidification and acid inhibition of glycolytic enzymes.Basically, fluoride acts to reduce the acid tolerance of the bacteria. It is most effective at acid pH values. In the acidic conditions of cariogenic plaque, fluoride at levels as low as 0.1 mM can cause complete arrest of glycolysis by intact cells ofStreptococcus mutans.Overall, the anticaries actions of fluoride appear to be complex, involving effects both on bacteria and on mineral phases. The antibacterial actions of fluoride appear themselves to be complex but to be dominated by weak-acid effects.” https://cdnsciencepub.com/doi/10.1139/m95-133#:~:text=Basica....

[throwaway290]

Fluoride reduces disease by reducing acid that bacteria poop out. Diseased gums and decaying teeth is great for things to leak into blood.