Newbie, looking at fast for repair

Hi all

I am looking at doing a fast for repair purposes (or at least improvement) of soft tissue tendons/ligaments/cartilage

I also have been told I have early osteoarthritus

- I just know I've had a crappy elbow for years! that hurts all the time unless I dont move it :(

I've developed the habit of 16 hours fasts each day and a pretty 'clean' diet already

I'd like if anyone has been through a fast with this aim

I think that It would need to be around 5 days to have a repair effect but Im not sure about this

I cant figure out whether black coffee is acceptable but Im leaning towards thinking it might be better without it (pretty much my only remaining vice)

Also how to get from where I am now to a 5 day fast, do I do a 1 day this month, 2 day next month etc

sorry for the long post and thank you for sticking with reading it!

Gary