{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T12:07:21Z","timestamp":1782475641293,"version":"3.54.5"},"reference-count":53,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,4,21]],"date-time":"2021-04-21T00:00:00Z","timestamp":1618963200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Nutr."],"abstract":"<jats:p>Sickle cell disease (SCD) is an inherited hemoglobinopathy caused by a variant (rs344) in the <jats:italic>HBB<\/jats:italic> gene encoding the \u03b2-globin subunit of hemoglobin. Chronic hemolytic anemia and increased erythropoiesis and RBC turnover in individuals with SCD can result in increased needs for folate and other B-vitamins. We assessed B-vitamin status, and the distribution of folate forms, including unmetabolized folic acid (UMFA), in Canadian children with SCD supplemented with 1 mg\/d folic acid (current routine practice). Non-fasted serum and plasma samples were analyzed for concentrations of folate, and vitamins B-2, B-6, and B-12. Eleven individuals (45% male; SCD type: HbSS <jats:italic>n<\/jats:italic> = 8, HbSC <jats:italic>n<\/jats:italic> = 2, HbS\u03b2<jats:sup>0<\/jats:sup>-Thal <jats:italic>n<\/jats:italic> = 1), with a median (IQR) age of 14 (7, 18) years, were included. Total folate concentrations were 3\u201327 times above the deficiency cut-off (10 nmol\/L), and 64% of children had elevated folate levels (&amp;gt;45.3 nmol\/L). UMFA (&amp;gt;0.23 nmol\/L) was detected in all children, and 36% of participants had elevated levels of UMFA (&amp;gt;5.4 nmol\/L). All children were vitamin B-12 sufficient (&amp;gt;150 pmol\/L), and the majority (55%) had sufficient B-6 status (&amp;gt;30 nmol\/L). Among this sample of Canadian children with SCD, there was limited evidence of B-vitamin deficiencies, but UMFA was detectable in all children.<\/jats:p>","DOI":"10.3389\/fnut.2021.642306","type":"journal-article","created":{"date-parts":[[2021,4,21]],"date-time":"2021-04-21T06:19:51Z","timestamp":1618985991000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":15,"title":["Detectable Unmetabolized Folic Acid and Elevated Folate Concentrations in Folic Acid-Supplemented Canadian Children With Sickle Cell Disease"],"prefix":"10.3389","volume":"8","author":[{"given":"Brock 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