For people living with Tourette’s syndrome that choose not to try medication, or are recommended not to take medication by their doctors, there have been studies done on how different food and drinks may affect their tics. Though little is known about this correlation, it is believed that nutritional factors such as food additives, allergies, and diets may be linked to the severity of tics in children and adults.
One study, done by four doctors from the Hanover Medical school in Hanover, Germany, aimed to increase the knowledge about the affects of food and drinks on tics. This group of doctors hypothesized that nutrition does not influence tics in patients with Tourette’s syndrome. They mailed out a standardized survey to 887 people that they had recruited from their Tourette’s outpatient clinic and the German Tourette’s self- aid group. The questionnaire asked the patients to rate how their tics were affected by 32 different foods, drinks, and diets. In order to try and get as many responses as possible, a prepaid addressed envelope was enclosed, as well as instructions to leave the survey anonymous. For children with Tourette’s syndrome under the age of sixteen, their parents were asked to complete the survey for them.
The survey had five parts, each separated from the rest and each having its’ own set of instructions in order to be as least confusing as possible. The first section asked patients to rate how severe thirty five different kinds of tics were for them, ranging from no tics of that kind, to extreme tics of that kind. The second part of the survey asked the patients to evaluate whether they had ever felt that certain food or drinks had influenced their tics. There were 32 different food and drink options, and six different rating choices ranging from no influence, marked deterioration, or an “I do not eat” response.
The third part of the survey asked patients if they had ever tried different diets or nutritional programs, and whether or not it had any influence on their tics. This part ranged from no influence to marked deterioration. The fourth part of the survey was only to be filled out by women who were pregnant or had been pregnant. This section was used to assess whether or not the intake of birth control, pregnancy, or breast feeding influenced their tics.
Finally, the last part of the survey asked patients about their medication history pertaining to treatment of tics. This part had a list of drugs commonly prescribed by doctors to help control tics. The patients were asked to complete this part if they had ever taken medication, or were currently taking medication to control their tics.
A little more than 25% of the patients that received the survey responded. Out of that 25%, 224 of the surveys were used for further analysis by the team. The average age of the respondent was 24.7 years, 75.9% were male, 23.7% female, and one not specified. 60% of the patients responded for themselves, and 40% were responding for a child under the age of 16.
After analyzing all of the data, the doctors concluded that there was a significant positive correlation between the deterioration of tics and certain foods. Those foods were coca-cola, coffee, black tea, preserving agents, refined white sugar, and sweeteners. No significant negative correlation was found during the analysis. There was a significant influence on the tics by diets and nutritional programs. Also, a significant improvement was seen after the use of certain drugs, including tiapride, sulpiride, riseridone, and citalopram. One medication, methylphenidate, showed a signification deterioration after usage. There were only a small number of patients that could answer the questions concerning pregnancy. However, their answers showed that there was no significant influence on tics caused by birth control pills, pregnancy or breastfeeding.
There were several limitations to this study that may have affected the outcome of the results. First, by using a standardized survey there was no control group, and the study was not performed in a controlled environment. Also, the results may have been biased based on the sample of patients, since the doctors used their own patients for the study. Second, because most people already eat a balanced diet every day and consume many different ingredients, it is difficult to specify which exact ingredient caused the severity of the tic.
The original hypothesis that nutrition would not affect the severity of tics was proven wrong by the results of the data. The doctors speculated that the ingredient that affects patients most severely was caffeine, because it stimulates an already overactive dopaminergic system in Tourette’s patients. Increased stimulation of this system increases the tics in the patients, so in the patients that experienced these increases, caffeine intake should be limited
Müller-Vahl, Kirsten R., et al. “The influence of different food and drink on tics in Tourette syndrome.” Acta Paediatrica 97.4 (2008): 442-446. Academic Search Premier. EBSCO. Web. 8 March 2010.