Both my dad and I have something in our sweat that causes certain metals to corrode...?

Question

Any watches that I wear start to corrode. I got a new Timex for Christmas and the side that faces my hand is already rotting(little holes, rough spots from pitted metal). My dad has a Seiko and his is okay. Whenever I wear new rings(anything except gold or platinum) they start to corrode and pit. Sometimes they even turn black on the inside and anywhere they touch my skin. Same thing for my dad.
Occasionally they'll even turn my fingers green(my husband and I bought matching engraved rings at Disney; mine turned black and my finger green and his was fine).
All my earrings have to be for sensitive ears or they get infected and the holes get black around the edges.
Anyone know why this happens or what causes it?

Answer 1

High acidity in sweat.

Answer 2

Not sure what it is but if it makes you feel better my brother and I are the same.