Thought I should share one my experiences with Comfrey - I have gum recession which caused a loose tooth - so I thought "comfrey causes skin to grow so maybe I could fatten up my gum around the loose tooth" - it worked but didn't secure the tooth - it just made the gum thicker in the area where I put it and because it wasn't normal, my attention kept being drawn there to this little mound as well as my tongue :-) It's been a year and has gone down about half.