Basically, it takes out the toxic metals, which is good. It also takes out a lot of important other things, which is bad. And it's very, very hard on the body. What happens unfortunately is often people are given it when they either don't have real heavy metal toxicity (everyone has some amount of these metals in their body). Even in some cases where they do have it, by the way, the damage is done already and taking it out would be more dangerous than leaving it in. So it's only used (appropriately) sometimes, and with extreme caution by someone with a license to do it and with a lot of instructions on how to take care of yourself in the meantime.
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"In my world it's a place of patterns and feel. In my world it's a haven for what is real. It's my world, nobody can steal it, but people like me, we live in the shadows." -Donna Williams