Do these things:
Use flouride free toothpaste
Filter your water with a dual filter that filters out chemicals and flouride, ( not all do) and makes the water alkaline. You can purchase pitchers, machines, faucet filters and plumbing filters that do this.

I went to school with a girl whose father wouldn't let her brush her teeth with anything but baking soda. She always acted like she knew a secret and couldn't say what. Her father worked for the government and that was also a secret that we couldn't know about it. It all makes sense now.