title: Folate, vitamin B12 and Homocysteine status in the post-folic acid fortification era in different subgroups of the Brazilian population attended to at a public health care center.
abstract: BACKGROUND
  Folate and vitamin B12 are essential nutrients, whose deficiencies are considerable public health problems worldwide, affecting all age groups. Low levels of these vitamins have been associated with high concentrations of homocysteine (Hcy) and can lead to health complications. Several genetic polymorphisms affect the metabolism of these vitamins. The aims of this study were to assess folate, vitamin B12 and homocysteine status in distinct Brazilian individuals after the initiation of folic acid fortification by Brazilian authorities and to investigate the effects of RFC1 A80G, GCPII C1561T and MTHFR C677T polymorphisms on folate, vitamin B12 and Hcy levels in these populations.
  
  
  METHODS
  A total of 719 individuals including the elderly, children, as well as pregnant and lactating women were recruited from our health care center. Folate, vitamin B12 and Hcy levels were measured by conventional methods. Genotype analyses of RFC1 A80G, GCPII C1561T and MTHFR C677T polymorphisms were performed by PCR-RFLP.
  
  
  RESULTS
  The overall prevalence of folate and vitamin B12 deficiencies were 0.3% and 4.9%, respectively. Folate deficiency was observed only in the elderly (0.4%) and pregnant women (0.3%), whereas vitamin B12 deficiency was observed mainly in pregnant women (7.9%) and the elderly (4.2%). Plasma Hcy concentrations were significantly higher in the elderly (33.6%). Pregnant women carrying the MTHFR 677TT genotype showed lower serum folate levels (p = 0.042) and higher Hcy levels (p = 0.003). RFC1 A80G and GCPII C1561T polymorphisms did not affect folate and Hcy levels in the study group. After a multivariate analysis, Hcy levels were predicted by variables such as folate, vitamin B12, gender, age and RFC1 A80G polymorphism, according to the groups studied.
  
  
  CONCLUSIONS
  Our results suggest that folate deficiency is practically nonexistent in the post-folic acid fortification era in the subgroups evaluated. However, screening for vitamin B12 deficiency may be particularly relevant in our population, especially in the elderly.
authors.affiliation: Department of Clinical Pathology, Faculty of Medical Sciences, University of Campinas, Rua Alexander Fleming, 105, Campinas, SP, 13083-881, Brazil. a_line00@hotmail.com.
authors.forename: Aline
authors.initials: A
authors.lastname: Barnabé
authors.affiliation: Hematology and Hemotherapy Center, University of Campinas, Rua Carlos Chagas, 480, Campinas, SP, 13083-878, Brazil. analessio@bol.com.br.
authors.forename: Ana Cláudia Morandi
authors.initials: AC
authors.lastname: Aléssio
authors.affiliation: Hematology and Hemotherapy Center, University of Campinas, Rua Carlos Chagas, 480, Campinas, SP, 13083-878, Brazil. lfbskayer@hotmail.com.
authors.forename: Luis Fernando
authors.initials: LF
authors.lastname: Bittar
authors.affiliation: Hematology and Hemotherapy Center, University of Campinas, Rua Carlos Chagas, 480, Campinas, SP, 13083-878, Brazil. brunamazetto_1@hotmail.com.
authors.forename: Bruna
authors.initials: B
authors.lastname: de Moraes Mazetto
authors.affiliation: Department of Pediatrics, Faculty of Medical Sciences, University of Campinas, Rua Tessália Vieira de Camargo, 126, Campinas, SP, 13083-887, Brazil. angelicabicudo@gmail.com.
authors.forename: Angélica M
authors.initials: AM
authors.lastname: Bicudo
authors.affiliation: Department of Clinical Pathology, Faculty of Medical Sciences, University of Campinas, Rua Alexander Fleming, 105, Campinas, SP, 13083-881, Brazil. erich@unicamp.br.
authors.forename: Erich V
authors.initials: EV
authors.lastname: de Paula
authors.affiliation: Department of Clinical Pathology, Faculty of Medical Sciences, University of Campinas, Rua Alexander Fleming, 105, Campinas, SP, 13083-881, Brazil. nelci@fcm.unicamp.br.
authors.forename: Nelci Fenalti
authors.initials: NF
authors.lastname: Höehr
authors.affiliation: Hematology and Hemotherapy Center, University of Campinas, Rua Carlos Chagas, 480, Campinas, SP, 13083-878, Brazil. joyce@unicamp.br.
authors.forename: Joyce M
authors.initials: JM
authors.lastname: Annichino-Bizzacchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology / Q000208:ethnology; D002268:Carboxypeptidases / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005494:Folic Acid Deficiency / Q000097:blood / Q000453:epidemiology* / Q000235:genetics / Q000378:metabolism; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007223:Infant; D007774:Lactation / Q000097:blood / Q000235:genetics; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011247:Pregnancy / Q000097:blood / Q000378:metabolism; D015995:Prevalence; D058978:Reduced Folate Carrier Protein / Q000235:genetics; D012307:Risk Factors; D012737:Sex Factors; D014805:Vitamin B 12 / Q000097:blood*; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000453:epidemiology* / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
chemical_list: D058978:Reduced Folate Carrier Protein; C548699:SLC19A1 protein, human; D006710:Homocysteine; D005492:Folic Acid; C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D002268:Carboxypeptidases; D014805:Vitamin B 12