title: Vitamin B12 among Vegetarians: Status, Assessment and Supplementation.
abstract: Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.
authors.affiliation: Vico Sant'andrea 5, Ritiro, Messina 98152, Italy. gianlucarizzo@email.it.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Rizzo
authors.affiliation: Unit of Gynecology and Obstetrics, Department of Human Pathology in Adulthood and Childhood, "G. Barresi", University of Messina, Via Consolare Valeria 1, Messina 98125, Italy. antlagana@unime.it.
authors.forename: Antonio Simone
authors.initials: AS
authors.lastname: Laganà
authors.affiliation: Department of General Surgery and Medical Surgical Specialties, University of Catania, Via S. Sofia 78, Catania 95124, Italy. agni.rap@live.it.
authors.forename: Agnese Maria Chiara
authors.initials: AM
authors.lastname: Rapisarda
authors.affiliation: Department of Gastroenterology and Digestive Endoscopy Maddalena Raimondi San Cataldo, Via Forlanini 5, San Cataldo, Caltanissetta 93017, Italy. giolaferrera@libero.it.
authors.forename: Gioacchina Maria Grazia
authors.initials: GM
authors.lastname: La Ferrera
authors.affiliation: Unit of Diabetology and Endocrino-Metabolic Diseases, Hospital for Emergency Cannizzaro, Via Messina 829, Catania 95126, Italy. buscemamassimo@gmail.com.
authors.forename: Massimo
authors.initials: M
authors.lastname: Buscema
authors.affiliation: Unit of Diabetology and Endocrino-Metabolic Diseases, Hospital for Emergency Cannizzaro, Via Messina 829, Catania 95126, Italy. paolarossetti@alice.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Rossetti
authors.affiliation: Unit of Diabetology and Endocrino-Metabolic Diseases, Hospital for Emergency Cannizzaro, Via Messina 829, Catania 95126, Italy. ang.nigro@gmail.com.
authors.forename: Angela
authors.initials: A
authors.lastname: Nigro
authors.affiliation: Unit of Diabetology and Endocrino-Metabolic Diseases, Hospital for Emergency Cannizzaro, Via Messina 829, Catania 95126, Italy. vince80@alice.it.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Muscia
authors.affiliation: Department of General Surgery and Medical Surgical Specialties, University of Catania, Via S. Sofia 78, Catania 95124, Italy. valentigaetano@gmail.com.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Valenti
authors.affiliation: Department of General Surgery and Medical Surgical Specialties, University of Catania, Via S. Sofia 78, Catania 95124, Italy. fabrizio.sapia@libero.it.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Sapia
authors.affiliation: Department of General Surgery and Medical Surgical Specialties, University of Catania, Via S. Sofia 78, Catania 95124, Italy. peppe_sarpietro@hotmail.com.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sarpietro
authors.affiliation: Department of General Surgery and Medical Surgical Specialties, University of Catania, Via S. Sofia 78, Catania 95124, Italy. micolziga@gmail.com.
authors.forename: Micol
authors.initials: M
authors.lastname: Zigarelli
authors.affiliation: Unit of Gynecology and Obstetrics, Department of Human Pathology in Adulthood and Childhood, "G. Barresi", University of Messina, Via Consolare Valeria 1, Messina 98125, Italy. vitalesalvatore@hotmail.com.
authors.forename: Salvatore Giovanni
authors.initials: SG
authors.lastname: Vitale
mesh_terms: D014676:Diet, Vegetarian; D019587:Dietary Supplements; D006801:Humans; D000066988:Vegetarians; D014805:Vitamin B 12; D014806:Vitamin B 12 Deficiency
chemical_list: D014805:Vitamin B 12
keywords: cardiovascular disease; cobalamin; deficiency; diagnostic markers; food sources; neurological symptoms; supplements; vegan; vegetarian; vitamin B12