Tourette syndrome, which causes embarrassing nervous facial tics, is a mystery to the medical profession.
Although incidence of the condition have increased four-fold in the past 20 years, few researchers are any the wiser as to the cause. One study in Rochester, New York, found that one out of four students in special education classes had a tic-related disorder, and over 18 per cent of the classroom students had some kind of a tic.
However, a study among 300 complementary practitioners, who specialize in Tourette therapy, found that environmental factors aggravated or triggered tics. Toxins, stimulants, allergens, and foods were all blamed as potential causes.
One study found that even a modest increase in room temperature could trigger tics. (Source: Townsend Letter for Doctors and Patients, January 2003; 22).