{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T11:04:08Z","timestamp":1791975848625,"version":"4.4.0"},"reference-count":56,"publisher":"BMJ","issue":"8","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2016,6,14]]},"published-print":{"date-parts":[[2016,8]]},"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>\n                      To assess serum B\n                      <jats:sub>12<\/jats:sub>\n                      , folate and the associated homocysteine (Hcy) levels among women of childbearing age in the UK and examine their association with dietary intake in relation to the UK Recommended Nutrient Intakes (RNIs) for B\n                      <jats:sub>12<\/jats:sub>\n                      and folate.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>Cross-sectional study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>Data from two publicly available National Diet and Nutrition Surveys (NDNS 2000\/2001 and 2008\/2012) were used. These were population-based surveys of randomly selected samples of adults which were carried out in their households.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>Women of childbearing age (aged 19\u201339\u2005years), representative of the UK population. Those who were pregnant or breastfeeding were excluded.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Outcome measures<\/jats:title>\n                    <jats:p>\n                      The associations between micronutrient intakes and blood levels of B\n                      <jats:sub>12<\/jats:sub>\n                      , folate and Hcy were assessed by correlation and stepwise linear regression. B\n                      <jats:sub>12<\/jats:sub>\n                      intake was divided into quintiles and plotted against blood B\n                      <jats:sub>12<\/jats:sub>\n                      and Hcy concentrations to determine the threshold of any associations.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      299 women from the first NDNS cohort had complete intake and biomarker data. The prevalence of serum vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      (\u2264150\u2005pmol\/L) and serum folate (\u226410\u2005nmol\/L) deficiency and hyperhomocysteinemia (\u226512\u2005\u00b5mol\/L) was 12.4%, 6.4% and 21.2%, respectively, despite seemingly adequate B\n                      <jats:sub>12<\/jats:sub>\n                      intakes (median 3.8\u2005\u03bcg\/day, 96% consumed more than the UK RNI of 1.5\u2005\u03bcg\/day). B\n                      <jats:sub>12<\/jats:sub>\n                      concentrations increased across all quintiles of intake with serum levels in quintiles 4 and 5 (median intake 4.9 and 7.1\u2005\u03bcg\/day, respectively) significantly higher than quintile 1. However, Hcy concentrations levelled off between quintiles 4 and 5. Comparison of micronutrient intake between the two surveys found that folate intake has reduced in the more recent cohort.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      The UK RNI for B\n                      <jats:sub>12<\/jats:sub>\n                      intake should be increased for women of childbearing age with intakes of around 5\u20137\u2005\u03bcg\/day likely to be associated with stable biomarker levels. B\n                      <jats:sub>12<\/jats:sub>\n                      levels should also be measured in women preconceptionally or in early pregnancy given the high rates of deficiency.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2016-011247","type":"journal-article","created":{"date-parts":[[2016,8,12]],"date-time":"2016-08-12T21:58:36Z","timestamp":1471039116000},"page":"e011247","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":45,"title":["Vitamin B\n                    <sub>12<\/sub>\n                    status in women of childbearing age in the UK and its relationship with national nutrient intake guidelines: results from two National Diet and Nutrition Surveys"],"prefix":"10.1136","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8549-2061","authenticated-orcid":false,"given":"Nithya","family":"Sukumar","sequence":"first","affiliation":[{"name":"Warwick Medical School, University of Warwick, Coventry, UK"},{"name":"Academic Department of Diabetes and Metabolism, George Eliot Hospital, Nuneaton, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonysunil","family":"Adaikalakoteswari","sequence":"additional","affiliation":[{"name":"Warwick Medical School, University of Warwick, Coventry, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hema","family":"Venkataraman","sequence":"additional","affiliation":[{"name":"Warwick Medical School, University of Warwick, Coventry, UK"},{"name":"Academic Department of Diabetes and Metabolism, George Eliot Hospital, Nuneaton, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hendramoorthy","family":"Maheswaran","sequence":"additional","affiliation":[{"name":"Warwick Medical School, University of Warwick, Coventry, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ponnusamy","family":"Saravanan","sequence":"additional","affiliation":[{"name":"Warwick Medical School, University of Warwick, Coventry, UK"},{"name":"Academic Department of Diabetes and Metabolism, George Eliot Hospital, Nuneaton, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2016,8,12]]},"reference":[{"key":"2025121410505164000_6.8.e011247.1","doi-asserted-by":"publisher","DOI":"10.1007\/s11154-012-9214-8"},{"key":"2025121410505164000_6.8.e011247.2","doi-asserted-by":"publisher","DOI":"10.1177\/1474651409358015"},{"key":"2025121410505164000_6.8.e011247.3","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.325.7374.1202"},{"key":"2025121410505164000_6.8.e011247.4","doi-asserted-by":"publisher","DOI":"10.1002\/biof.17"},{"key":"2025121410505164000_6.8.e011247.5","doi-asserted-by":"publisher","DOI":"10.1093\/qjmed\/hcg043"},{"key":"2025121410505164000_6.8.e011247.6","doi-asserted-by":"publisher","DOI":"10.1001\/jama.288.15.1867"},{"key":"2025121410505164000_6.8.e011247.7","doi-asserted-by":"crossref","first-page":"1385","DOI":"10.1093\/ajcn\/76.6.1385","article-title":"Preconception homocysteine and B vitamin status and birth outcomes in Chinese women","volume":"76","author":"Ronnenberg","year":"2002","journal-title":"Am J Clin Nutr"},{"key":"2025121410505164000_6.8.e011247.8","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.115.123083"},{"key":"2025121410505164000_6.8.e011247.9","first-page":"362","article-title":"Spina bifida and anencephaly before and after folic acid mandate\u2014 United States, 1995\u20131996 and 1999\u20132000","volume":"53","author":"Centers for Disease Control and Prevention (CDC)","year":"2004","journal-title":"MMWR Morb Mortal Wkly Rep"},{"key":"2025121410505164000_6.8.e011247.10","doi-asserted-by":"publisher","DOI":"10.1097\/01.ede.0000257063.77411.e9"},{"key":"2025121410505164000_6.8.e011247.11","doi-asserted-by":"publisher","DOI":"10.1016\/S0015-0282(00)01595-8"},{"key":"2025121410505164000_6.8.e011247.12","doi-asserted-by":"crossref","first-page":"962","DOI":"10.1093\/ajcn\/71.4.962","article-title":"Plasma total homocysteine, pregnancy complications, and adverse pregnancy outcomes: the Hordaland Homocysteine study","volume":"71","author":"Vollset","year":"2000","journal-title":"Am J Clin Nutr"},{"key":"2025121410505164000_6.8.e011247.13","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.111.016212"},{"key":"2025121410505164000_6.8.e011247.14","doi-asserted-by":"crossref","first-page":"883","DOI":"10.3892\/mmr.2012.763","article-title":"DNA methylation in the human placenta and fetal growth (review)","volume":"5","author":"Koukoura","year":"2012","journal-title":"Mol Med Rep"},{"key":"2025121410505164000_6.8.e011247.15","doi-asserted-by":"publisher","DOI":"10.1016\/j.contraception.2011.07.013"},{"key":"2025121410505164000_6.8.e011247.16","doi-asserted-by":"publisher","DOI":"10.3109\/08880018.2013.829894"},{"key":"2025121410505164000_6.8.e011247.17","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.112.056382"},{"key":"2025121410505164000_6.8.e011247.18","doi-asserted-by":"publisher","DOI":"10.1038\/sj.ejcn.1602212"},{"key":"2025121410505164000_6.8.e011247.19","doi-asserted-by":"crossref","first-page":"1863","DOI":"10.1093\/jn\/137.8.1863","article-title":"Longitudinal study of the effect of pregnancy on maternal and fetal cobalamin status in healthy women and their offspring","volume":"137","author":"Murphy","year":"2007","journal-title":"J Nutr"},{"key":"2025121410505164000_6.8.e011247.20","first-page":"1","article-title":"Dietary reference values for food energy and nutrients for the United Kingdom. Report of the Panel on Dietary Reference Values of the Committee on Medical Aspects of Food Policy","volume":"41","year":"1991","journal-title":"Rep Health Soc Subj (Lond)"},{"key":"2025121410505164000_6.8.e011247.21","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1079\/PNS19920007","article-title":"Dietary reference values","volume":"51","author":"Whitehead","year":"1992","journal-title":"Proc Nutr Soc"},{"key":"2025121410505164000_6.8.e011247.22","doi-asserted-by":"crossref","first-page":"2423","DOI":"10.1093\/ajcn\/34.11.2423","article-title":"Evidence regarding the minimal daily requirement of dietary vitamin B12","volume":"34","author":"Baker","year":"1981","journal-title":"Am J Clin Nutr"},{"key":"2025121410505164000_6.8.e011247.23","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1111\/j.1365-2141.1966.tb05635.x","article-title":"Vitamin B-12-folate interrelationships in megaloblastic anaemia","volume":"12","author":"Cooper","year":"1966","journal-title":"Br J Haematol"},{"key":"2025121410505164000_6.8.e011247.24","first-page":"4150","article-title":"Scientific Opinion on Dietary Reference Values for cobalamin (vitamin B12)","volume":"13","author":"EFSA NDA Panel (EFSA Panel on Dietetic Products NaA","year":"2015","journal-title":"EFSA J"},{"key":"2025121410505164000_6.8.e011247.25","doi-asserted-by":"publisher","DOI":"10.1017\/S1368980011002643"},{"key":"2025121410505164000_6.8.e011247.26","unstructured":"Institute of Medicine. Dietary reference intakes for thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington DC: National Academies Press, 1998:306\u201356."},{"key":"2025121410505164000_6.8.e011247.27","unstructured":"Henderson L , Gregory J , Swan G . The national diet & nutrition survey: adults aged 19 to 64 years. Volume 1. Types and quantities of foods consumed. London: The Stationery Office, 2002."},{"key":"2025121410505164000_6.8.e011247.28","unstructured":"Henderson L , Irving K , Gregory J , et al . The national diet & nutrition survey: adults aged 19 to 64 years. Volume 3. Vitamin and mineral intake and urinary analytes. London: The Stationery Office, 2003."},{"key":"2025121410505164000_6.8.e011247.29","unstructured":"Bates B , Lennox A , Prentice A , et al . National Diet and Nutrition Survey: Results from Years 1, 2, 3 and 4 (combined) of the Rolling Programme (2008\/2009\u20132011\/2012). 2014. https:\/\/www.gov.uk\/government\/uploads\/system\/uploads\/attachment_data\/file\/310995\/NDNS_Y1_to_4_UK_report.pdf"},{"key":"2025121410505164000_6.8.e011247.30","unstructured":"Skinner C , Holmes D . The 2000-01 National Diet and Nutrition Survey of Adults aged 19-64 years: The impact of non-response. In National Diet and Nutrition survey Adults Aged 19\u201364 years. Appendix E. 2002. http:\/\/wwwfoodgovuk\/science\/101717\/ndnsdocuments\/ndnsappendicies"},{"key":"2025121410505164000_6.8.e011247.31","doi-asserted-by":"crossref","first-page":"613","DOI":"10.3109\/00365519709055285","article-title":"An external quality assessment study on the analysis of methylmalonic acid and total homocysteine in plasma","volume":"57","author":"M\u00f8ller","year":"1997","journal-title":"Scand J Clin Lab Invest"},{"issue":"1","key":"2025121410505164000_6.8.e011247.32","doi-asserted-by":"crossref","first-page":"253S","DOI":"10.1093\/ajcn\/59.1.253S","article-title":"Approaches to analysis of dietary data: relationship between planned analyses and choice of methodology","volume":"59","author":"Beaton","year":"1994","journal-title":"Am J Clin Nutr"},{"key":"2025121410505164000_6.8.e011247.33","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.111.013441"},{"issue":"2","key":"2025121410505164000_6.8.e011247.34","first-page":"S1","article-title":"Folate and vitamin B12 deficiencies. Proceedings of a WHO technical consultation held 18\u201321 October, 2005, in Geneva, Switzerland","volume":"29","year":"2008","journal-title":"Food Nutr Bull"},{"key":"2025121410505164000_6.8.e011247.35","doi-asserted-by":"publisher","DOI":"10.1373\/clinchem.2003.021634"},{"key":"2025121410505164000_6.8.e011247.36","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1093\/clinchem\/47.6.1001","article-title":"Influence of vitamin-optimized plasma homocysteine cutoff values on the prevalence of hyperhomocysteinemia in healthy adults","volume":"47","author":"Fokkema","year":"2001","journal-title":"Clin Chem"},{"key":"2025121410505164000_6.8.e011247.37","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1093\/ajcn\/60.1.2","article-title":"Prevalence of cobalamin deficiency in the Framingham elderly population","volume":"60","author":"Lindenbaum","year":"1994","journal-title":"Am J Clin Nutr"},{"key":"2025121410505164000_6.8.e011247.38","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.112.033951"},{"key":"2025121410505164000_6.8.e011247.39","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.2009.28082"},{"key":"2025121410505164000_6.8.e011247.40","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.2008.26598"},{"key":"2025121410505164000_6.8.e011247.41","doi-asserted-by":"publisher","DOI":"10.3945\/jn.115.210757"},{"key":"2025121410505164000_6.8.e011247.42","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1186\/s12937-015-0095-z","article-title":"The association between maternal dietary micronutrient intake and neonatal anthropometry\u2014secondary analysis from the ROLO study","volume":"14","author":"Horan","year":"2015","journal-title":"Nutr J"},{"key":"2025121410505164000_6.8.e011247.43","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2796.2011.02485.x"},{"key":"2025121410505164000_6.8.e011247.44","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0012244"},{"key":"2025121410505164000_6.8.e011247.45","doi-asserted-by":"publisher","DOI":"10.3945\/jn.112.169524"},{"key":"2025121410505164000_6.8.e011247.46","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0089504"},{"key":"2025121410505164000_6.8.e011247.47","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1159\/000170890","article-title":"Folate, vitamin B12 and homocysteine status in women of childbearing age: baseline data of folic acid wheat flour fortification in Iran","volume":"53","author":"Abdollahi","year":"2008","journal-title":"Ann Nutr Metab"},{"key":"2025121410505164000_6.8.e011247.48","doi-asserted-by":"crossref","first-page":"358","DOI":"10.3906\/sag-1401-25","article-title":"Premarital screening of 466 Mediterranean women for serum ferritin, vitamin B12, and folate concentrations","volume":"45","author":"Karabulut","year":"2015","journal-title":"Turk J Med Sci"},{"key":"2025121410505164000_6.8.e011247.49","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1024\/0300-9831\/a000014","article-title":"Iron, folate, and B(12) deficiencies and their associations with anemia among women of childbearing age in a rural area in Northern China","volume":"80","author":"Zhu","year":"2010","journal-title":"Int J Vitam Nutr Res"},{"key":"2025121410505164000_6.8.e011247.50","doi-asserted-by":"crossref","first-page":"5103","DOI":"10.3390\/nu6115103","article-title":"Micronutrient status in female university students: iron, zinc, copper, selenium, vitamin B12 and folate","volume":"6","author":"Fayet-Moore","year":"2014","journal-title":"Nutrients"},{"key":"2025121410505164000_6.8.e011247.51","doi-asserted-by":"publisher","DOI":"10.1038\/ejcn.2010.142"},{"key":"2025121410505164000_6.8.e011247.52","doi-asserted-by":"publisher","DOI":"10.1111\/nure.12001"},{"key":"2025121410505164000_6.8.e011247.53","unstructured":"Scientific Advisory Committee on Nutrition. Folate and disease prevention. Food Standards Agency and the Department of Health, 2006."},{"key":"2025121410505164000_6.8.e011247.54","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1093\/ajcn\/86.3.718","article-title":"Trends in blood folate and vitamin B-12 concentrations in the United States, 1988 2004","volume":"86","author":"Pfeiffer","year":"2007","journal-title":"Am J Clin Nutr"},{"key":"2025121410505164000_6.8.e011247.55","doi-asserted-by":"publisher","DOI":"10.3945\/ajcn.2008.26947C"},{"key":"2025121410505164000_6.8.e011247.56","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0709487104"}],"container-title":["BMJ Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bmjopen-2016-011247","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,14]],"date-time":"2025-12-14T18:51:01Z","timestamp":1765738261000},"score":1,"resource":{"primary":{"URL":"https:\/\/bmjopen.bmj.com\/lookup\/doi\/10.1136\/bmjopen-2016-011247"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,8]]},"references-count":56,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2016,8,12]]},"published-print":{"date-parts":[[2016,8]]}},"alternative-id":["10.1136\/bmjopen-2016-011247"],"URL":"https:\/\/doi.org\/10.1136\/bmjopen-2016-011247","relation":{},"ISSN":["2044-6055","2044-6055"],"issn-type":[{"value":"2044-6055","type":"print"},{"value":"2044-6055","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,8]]}}}