I think it is a deficiency, I had the same problem now it's very rare and very minimal. It was worse for me through my pregnancies, it was nerves in my legs that's why when I tried lotions and things nothing helped. When I started taking supplements and eating mostly fruits and veggies it got better. I can't tell you what kind of deficiency because I never tried to single it out was just glad it was gone.
I did just start taking a womans one a day multi vitamin.... i'm hoping that will help.