1. CFS Clinical Unit, Vall d'Hebron Research Institute, Vall d'Hebron University Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain.
2. Research Laboratory, Dental School, University of Sevilla, Sevilla, Spain.
3. Vitae Natural Nutrition, S.L., Sant Cugat del Vallès, Barcelona, Spain.
4. Psychiatry Department and Legal Medicine, Vall d'Hebron University Hospital (CIBERSAM), Instituto de Salud Carlos III, Universitat Autònoma de Barcelona, Barcelona, Spain.