I have not been formally diagnosed, but I believe I am suffering from this. I went to see an osteopath that works with mind, body and soul. She is certain that I have a mineral imbalance. Of course I don't believe it, I'm deathly afraid I have MS as I have a lot of pins and needles. However, she mentioned a friend of hers who plays a lot of tennis outdoors here in Florida who had the exact symptoms as me and it was a mineral imbalance, specifically magnesium. The websites from traditional medicine all say it is rare to have a magnesium deficiency, but from other things I've read, it is very difficult to find a dificiency through a routine blood test as magnesium is stored in the tissue of the body, only 1% resides in the blood. Also, magnesium gets depleted through sweat as all minerals do. If you are going to supplement, do research and get a good quality supplement that is bioavailable, not a tablet.