I've not tried bentonite chelation although I looked into it. I decided against it due to its possible affects on good bacteria in the gut, constipation and the fact it contains trace amounts of aluminium. My DD already had enough gut issues and I didn't want to use a treatment that may exasperate them, plus I felt she was too young and wouldn't be overly accommodating anyway.
I did use alternative methods such as eating foods high in sulphur (onion/garlic in particular), epsom salts baths, and improving good gut bacteria through eating a lot of fermented foods and the removal of yeast from the diet. I did see quite large improvements. On an interesting point, DD's hair samples showed quite low metals, which is usual for autistic children, combined with her blood tests (which showed high levels) it showed she was not excreting them like she should. I haven't taken her back to be retested yet though - but we would initially want to see higher levels in her hair, not less.
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