My dad has been wearing one he says for a number of years.
The inside of his elbow started to pain suddenly. He was telling me and says that he might rub some ointment on it and see if it helps.
Then suddenly he remembered that he had taken off the bracelet a few days before and did not put it back on. I told him ok, do not rub the ointment, put the bracelet back on and see what happens.
He called me back 2 days later and said the pain is all gone.
So I dunno