1. Surgery and Medical Surgical Specialities Department, Faculty of Medicine and Health Sciences, University of Oviedo, Oviedo, Asturias, Spain.
2. Paediatric Gastroenterology and Nutrition Unit, Hospital Universitario Central de Asturias (HUCA), Oviedo, Asturias, Spain.
3. Independent Anthropologist, Oviedo, Asturias, Spain.