Removing waste, not "toxins". And unless you are severely dehydrated, they work fine. From: https://journals.lww.com/nutritiontodayonline/Pages/articleviewer.

Removing waste, not "toxins". And unless you are severely dehydrated, they work fine. From: https://journals.lww.com/nutritiontodayonline/Pages/articleviewer.aspx?year=2010&issue=11001&article=00010&type=Fulltext https://journals.lww.com/nutritiontodayonline/Pages/articlev... > Only a drastic reduction of total body water is able to impair renal function in healthy kidneys