One-word answer to critics: toothpaste.
Yes. Read the warning labels on the toothpaste.
Two point response:
1) You don't swallow gallons toothpaste every week, do you?
2) Sodium fluoride and calcium fluoride are very, *very* different substances. Sodium fluoride is the poison that gets dumped into municipal water supplies. Calcium fluoride is what helps teeth and bones form properly. Huge difference.