It might sound weird, but I've been progressively losing weight by religiously brushing my teeth after eating anything.
I used to have a problem of eating small things like candies and biscuits randomly, as a way to control anxiety. Now I think twice before eating anything, because I don't want to go and brush my teeth again. After some time doing that, I ended regulating myself and eating at specific times, with no extra eating between them.
Yes, it's a thing. Brushing too often can damage the enamel and lead to some issues.
However, in my case, it's my inertia and laziness that are the stronger forces preventing me from taking some extra snacks, and not the fear of overbrushing. 😅