The best health advice I ever received was from an Ear Nose and Throat specialist who I saw because I had a very bad sore throat with a lot of infection. I’d taken antibiotics for months and it wasn’t moving.
His advice (which I have followed ever since with no sore throats since a clean pink tongue and much greater confidence in the freshness of my breath and a lot fewer upper respiratory tract infections and complications):
Stir one teaspoon of bi-carb soda into several centimetres of water in a glass and gargle with it (and spit out) then rinse toothbrush in what remains in the glass. Do this morning and evening every day when cleaning teeth.
We have a bowl of bi-carb soda by the bathroom handbasin with a separate small bowl to hold the teaspoon (because it gets wet when stirring so don’t put back in the bi-carb until it dries).
Since then we’ve found out a lot more about bi-carb’s bacterial control properties starting with watching a butcher scrub his chopping block down with bi-carb to sterilize it. It is good for wiping out the handbasin.