I've this on and off for about 5 years now. I've never got to the bottom of it and went thru all the neurological tests. There's a great site named after the complaint you've got which is called Benign Fascisulation Syndrome. Lot's of people think they've got ALS/Motor Neurone disease and freak out initially but it's important to remember that a person will present with muscle weakness way before the twitches start. You haven't got that, so don't even be tempted to go down this road.

Best

Adam

Mineral imbalances may cause muscle twitches. (Along with a variety of other things of course)

The main 3 would be calcium, magnesium and potassium.

Assess your diet for a deficiency or imbalance of any of these, whether you've been having lots of calcium thus imbalancing magnesium or lots of sodium thus imbalancing potassium.

As the previous poster states its important to know what to supplement, if you notice your symptoms worsening, you can bet it was the wrong thing! ;-)

Try here for some info on minerals and spasms. http://www.acu-cell.com/dis-mus.html