{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T08:52:42Z","timestamp":1787647962211,"version":"build-2736575974"},"reference-count":36,"publisher":"American Diabetes Association","issue":"2","license":[{"start":{"date-parts":[[2021,9,1]],"date-time":"2021-09-01T00:00:00Z","timestamp":1630454400000},"content-version":"vor","delay-in-days":3516,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/3.0\/"}],"content-domain":{"domain":["diabetesjournals.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2012,2,1]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>To describe the prevalence of biochemical B12 deficiency in adults with type 2 diabetes taking metformin compared with those not taking metformin and those without diabetes, and explore whether this relationship is modified by vitamin B12 supplements.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESEARCH DESIGN AND METHODS<\/jats:title>\n                    <jats:p>Analysis of data on U.S. adults \u226550 years of age with (n = 1,621) or without type 2 diabetes (n = 6,867) from the National Health and Nutrition Examination Survey (NHANES), 1999\u20132006. Type 2 diabetes was defined as clinical diagnosis after age 30 without initiation of insulin therapy within 1 year. Those with diabetes were classified according to their current metformin use. Biochemical B12 deficiency was defined as serum B12 concentrations \u2264148 pmol\/L and borderline deficiency was defined as &amp;gt;148 to \u2264221 pmol\/L.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>Biochemical B12 deficiency was present in 5.8% of those with diabetes using metformin compared with 2.4% of those not using metformin (P = 0.0026) and 3.3% of those without diabetes (P = 0.0002). Among those with diabetes, metformin use was associated with biochemical B12 deficiency (adjusted odds ratio 2.92; 95% CI 1.26\u20136.78). Consumption of any supplement containing B12 was not associated with a reduction in the prevalence of biochemical B12 deficiency among those with diabetes, whereas consumption of any supplement containing B12 was associated with a two-thirds reduction among those without diabetes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>Metformin therapy is associated with a higher prevalence of biochemical B12 deficiency. The amount of B12 recommended by the Institute of Medicine (IOM) (2.4 \u03bcg\/day) and the amount available in general multivitamins (6 \u03bcg) may not be enough to correct this deficiency among those with diabetes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.2337\/dc11-1582","type":"journal-article","created":{"date-parts":[[2011,12,17]],"date-time":"2011-12-17T00:57:04Z","timestamp":1324083424000},"page":"327-333","update-policy":"https:\/\/doi.org\/10.2337\/ada-journal-policies","source":"Crossref","is-referenced-by-count":207,"title":["Association of Biochemical B12 Deficiency With Metformin Therapy and Vitamin B12 Supplements"],"prefix":"10.2337","volume":"35","author":[{"given":"Lael","family":"Reinstatler","sequence":"first","affiliation":[{"name":"Rollins School of Public Health, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan Ping","family":"Qi","sequence":"additional","affiliation":[{"name":"Rollins School of Public Health, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rebecca S.","family":"Williamson","sequence":"additional","affiliation":[{"name":"Rollins School of Public Health, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua V.","family":"Garn","sequence":"additional","affiliation":[{"name":"Rollins School of Public Health, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"suffix":"Jr.","given":"Godfrey P.","family":"Oakley","sequence":"additional","affiliation":[{"name":"Rollins School of Public Health, Emory University, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1167","published-online":{"date-parts":[[2012,1,16]]},"reference":[{"key":"2022031302302027900_B1","volume-title":"Food and Nutrition Board. 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