One of my sons had the beginnings of Tourette Syndrome when he was little - eye blinking, facial twitching, eye tics, etc. Our regular doctor didn't have any advice for us, so I researched my son's condition using the book library at the local health food store. The indications were that he was low in magnesium, so we changed his diet to get more magnesium rich foods and give him magnesium supplements for a few days crushed in yogurt. It worked great. The tics, twitches and eye blinking all stopped within a few days. We made the diet changes permanent, and for years I never gave the tics another thought. The only other time my son developed tics and twitches was when he was older and went on vacation with friends (without mom around to remind him to eat his vegetables!) and ate junk food for a few days, but the tics and twitches cleared up after he got home and ate healthier foods, including vegetables and nuts, for for a few days.
I find it odd that kids with tics, twitches and other signs related to Tourette Syndrome do not seem to be regularly checked for magnesium deficiency. A web page on magnesium in diet from the U.S. National Library of Medicine, National Institutes of Health's web site clearly notes that muscle twitching is a sign of magnesium deficiency. Yet based on my experience with my son and the experiences of parents who write to me, children with symptoms of tics and muscle twitching who are taken to the doctor are unfortunately not usually asked about their diets or checked for low magnesium levels.