{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T16:48:33Z","timestamp":1787503713352,"version":"build-2736575974"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,18]],"date-time":"2022-02-18T00:00:00Z","timestamp":1645142400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: Tourette syndrome (TS) is a neurodevelopmental disorder characterized by tics and co-occurring disorders. It has been suggested that anxiety occurs in 2\u201345% patients affected by Tourette syndrome. Despite dietary and nutritional factors have been found to affect a range of neurological conditions, no more studies have investigated the relationship between nutritional supplements and tics. Objective: To evaluate the effectiveness of supplementation of both L-Theanine and Vitamin B6 in reducing tics and co-occurring disorders in a sample of youth with chronic tic disorder (CTD) or Tourette syndrome with anxiety symptoms. Design: A open-label trial. Patients affected by Tourette syndrome were randomized to receive nutritional supplements based on L-Theanine and vitamin B6, or psychoeducation (PE). Participants: 34 children (30 boys and 4 girls) aged between 4 and 17 years affected by Tourette syndrome or chronic tic disorder, associated with anxiety symptoms. Results: Patients in both groups showed a reduction in the severity of tic and anxiety symptoms. Supplementation with L-Theanine and vitamin B6 was significantly more effective than psychoeducation in reducing tics and co-occurring disorders, as measured by neuropsychological findings. Conclusions: Supplementation of both L-Theanine and Vitamin B6 may help in the treatment of tic disorders associated with anxious symptoms. Between-group differences in clinician-rated severity did reach statistical significance only for tics. Despite this finding, further placebo-controlled trials are needed.<\/jats:p>","DOI":"10.3390\/nu14040852","type":"journal-article","created":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T08:22:19Z","timestamp":1645431739000},"page":"852","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Use of Nutritional Supplements Based on L-Theanine and Vitamin B6 in Children with Tourette Syndrome, with Anxiety Disorders: A Pilot Study"],"prefix":"10.3390","volume":"14","author":[{"given":"Renata","family":"Rizzo","sequence":"first","affiliation":[{"name":"Child and Adolescent Neurology and Psychiatric Section, Department of Clinical and Experimental Medicine, Catania University, 95124 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana","family":"Prato","sequence":"additional","affiliation":[{"name":"Child and Adolescent Neurology and Psychiatric Section, Department of Clinical and Experimental Medicine, Catania University, 95124 Catania, Italy"},{"name":"Department of Cognitive Sciences, Psychology, Education and Cultural Studies, University of Messina, 98121 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miriam","family":"Scerbo","sequence":"additional","affiliation":[{"name":"Child and Adolescent Neurology and Psychiatric Section, Department of Clinical and Experimental Medicine, Catania University, 95124 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica","family":"Saia","sequence":"additional","affiliation":[{"name":"Child and Adolescent Neurology and Psychiatric Section, Department of Clinical and Experimental Medicine, Catania University, 95124 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6302-2686","authenticated-orcid":false,"given":"Rita","family":"Barone","sequence":"additional","affiliation":[{"name":"Child and Adolescent Neurology and Psychiatric Section, Department of Clinical and Experimental Medicine, Catania University, 95124 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"Curatolo","sequence":"additional","affiliation":[{"name":"Child Neurology and Psychiatry Unit, Systems Medicine Department, University of Rome Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"American-Psychiatric-Association (2013). 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