title: High prevalence of suboptimal vitamin B12 status in young adult women of South Asian and European ethnicity.
abstract: Suboptimal vitamin B12 (B12) status has been associated with an increased risk of congenital anomalies, preterm birth, and childhood insulin resistance. South Asians - Canada's largest minority group - and women of reproductive age are vulnerable to B12 deficiency. This study aimed to assess the prevalence of and factors associated with B12 deficiency and suboptimal B12 status in a convenience sample of young adult women of South Asian and European descent in Metro Vancouver. We measured serum B12, holotranscobalamin, plasma methylmalonic acid, red blood cell and plasma folate, and hematologic parameters in 206 nonpregnant, healthy women aged 19-35 years. Categorization for B12 status adhered to serum B12 cutoffs for deficiency (<148 pmol/L) and suboptimal B12 status (148-220 pmol/L). We collected demographic, lifestyle, and dietary intake data and conducted genotyping for common genetic variants linked to B-vitamin metabolism. The prevalence of deficiency and suboptimal B12 status were 14% and 20%, respectively. Serum vitamin B12 concentrations were negatively associated with oral contraceptive use and first-generation immigrant status, and positively with dietary B12 intake and B12 supplement use. The prevalence of B12 inadequacy in this sample of highly educated women is higher than in the general Canadian population. In light of maternal and fetal health risks associated with B12 inadequacy in early-pregnancy, practitioners should consider monitoring B12 status before and during early pregnancy, especially in immigrants and women with low dietary B12 intakes including non-users of vitamin supplements.
authors.affiliation: a Food Nutrition and Health, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Teo A W
authors.initials: TA
authors.lastname: Quay
authors.affiliation: a Food Nutrition and Health, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Theresa H
authors.initials: TH
authors.lastname: Schroder
authors.affiliation: a Food Nutrition and Health, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Marta
authors.initials: M
authors.lastname: Jeruszka-Bielak
authors.affiliation: a Food Nutrition and Health, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Wangyang
authors.initials: W
authors.lastname: Li
authors.affiliation: b Division of Endocrinology, Department of Pediatrics, University of British Columbia, British Columbia, Canada.|c Child and Family Research Institute, Vancouver British Columbia, Canada.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Devlin
authors.affiliation: a Food Nutrition and Health, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Susan I
authors.initials: SI
authors.lastname: Barr
authors.affiliation: a Food Nutrition and Health, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.|c Child and Family Research Institute, Vancouver British Columbia, Canada.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Lamers
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D044466:Asian People / Q000235:genetics; D015415:Biomarkers / Q000097:blood; D001955:British Columbia / Q000453:epidemiology; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D005260:Female; D020022:Genetic Predisposition to Disease; D006306:Health Surveys; D006801:Humans; D008019:Life Style; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution; D012737:Sex Factors; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014805:Vitamin B 12 / Q000097:blood* / Q000627:therapeutic use; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000208:ethnology* / Q000235:genetics; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: D015415:Biomarkers; D014805:Vitamin B 12
keywords: South Asian; acide méthylmalonique plasmatique; deficiency; déficience; facteurs du mode de vie; holotranscobalamin; holotranscobalamine; lifestyle factors; maternal health; methylmalonic acid; periconceptional; périconception; santé maternelle; statut suboptimal; suboptimal status; sud-asiatique; supplement use; utilisation de suppléments; vitamin B12; vitamine B12