As far as I can tell, no mechanism exists except for large scale water treatment plants, which are controlled to a strict 0.7 parts F to 1 million parts water. There used to be supplement pills you could get for free at the pharmacy, many years ago, but now you have to get a medical prescription and pay. I'm disappointed by all the people who ignore the question and instead give their personal opinion. None of you are qualified to give medical opinions, so shut it. Also to anyone who reads these opinions: make note of the fact these people are not doctors and have no knowledge whatsoever of your personal health - try not to be persuaded by their ignorant loud-mouthed opinions. Just talk to your own doctor.