{"id":15011,"date":"2026-10-14T15:00:00","date_gmt":"2026-10-14T15:00:00","guid":{"rendered":"https:\/\/bioprofile.com\/?page_id=15011"},"modified":"2026-11-05T00:04:04","modified_gmt":"2026-11-05T00:04:04","slug":"vitamin-b12","status":"publish","type":"page","link":"https:\/\/bioprofile.com\/en\/biomarkers\/vitamin-b12\/","title":{"rendered":"Vitamin B12"},"content":{"rendered":"\n<div id=\"content\" tabindex=\"-1\"><\/div>\n<style>@import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:ital,wght@0,400;0,600;0,700;0,800;1,400&display=swap');\n\/* ===========================================================================\n   BioProfile advertorial, the design Jesse approved on 2026-07-30, expressed\n   as a WordPress design system.\n\n   THE @import IS LOAD BEARING and must stay the first thing in this sheet (a\n   CSS @import after any rule is dropped by the parser). elementor_canvas does\n   not enqueue the theme's fonts, so without it the whole page falls back to the\n   system font. Caught by LOOKING at the live page on 2026-07-30, right after\n   the template was switched to canvas.\n\n   Everything is scoped to `.bp-adv`, so nothing here can reach the rest of\n   bioprofile.com, and core blocks are styled BY ELEMENT so a heading, a\n   paragraph, a quote, a list, an image or a button inserted by hand inside the\n   advertorial comes out on-design with no class to remember.\n\n   Jesse's design feedback, 2026-07-29 23:38, point by point:\n   1. the light green and the dark green are the preferred colours; grey may be\n      used but the page must NOT open grey;\n   2. more colour and variation across sections, e.g. a colour block on the left\n      or the right side of a section, without overdesign;\n   3. ONE H1, plain text on white; everything else H2 or H3; an H2 may carry its\n      own background colour so the page can be read from the headings alone; an\n      H3 keeps its section background and gets a bigger font size;\n   4. reuse the results page design feel;\n   5. Written by \/ Verified by, the placeholder blocks and noindex stay.\n\n   COLOUR PROVENANCE. Not one hex is invented.\n   - #b7cb32  LIGHT GREEN, brand manual \"colours rejuvenation protocol\"\n              (R183 G203 B51). Same value as --bp-lime in\n              brands\/bioprofile\/brand\/tokens.md.\n   - #006b62  DARK GREEN, brand manual, nourish the cells (R0 G107 B98).\n   - #005859  brand manual primary teal, the value the brand is built on.\n   - #228a62  brand manual, challenge the body (R34 G138 B98).\n   - #7ca64c  brand manual, calm the mind (R124 G166 B76).\n   - #dbd4cd  brand manual \"additional color\", the warm neutral.\n   - #B7CB3329 is the brand token --bp-lime-soft (light green at 16 percent).\n   - the gradients are the brand token layer's own, copied verbatim.\n\n   SPECIFICITY NOTE. Elementor's global kit emits `.elementor-kit-6 h2` style\n   rules at (0,1,1). Element rules below are written `.bp-adv h2`, also (0,1,1),\n   and win on source order because this sheet is inline in the body while the\n   kit is a <link> in the head. Component rules that MUST NOT lose carry two\n   classes, e.g. `.bp-adv .wp-block-button__link`.\n\n   LAYOUT NOTE. Vertical rhythm uses `margin-block` and never the `margin`\n   shorthand, so the measure rule `.bp-adv-sec > * { margin-inline: auto }` can\n   centre a block without being outranked by its own element rule.\n   =========================================================================== *\/\n\n.bp-adv {\n  --bp-ink: #212527;\n  --bp-teal: #005859;\n  --bp-forest: #006B62;\n  --bp-emerald: #228A62;\n  --bp-olive: #7CA64C;\n  --bp-lime: #B7CB33;\n  --bp-lime-soft: #B7CB3329;\n  --bp-sand: #DBD4CB;\n  --bp-white: #FFFFFF;\n  --bp-foot: #6b6b6b;\n  --bp-grad-dark: linear-gradient(237deg, rgba(0,88,89,0.00) 62.94%, #005859 100%), linear-gradient(90deg, rgba(34,138,98,0.00) 40%, #228A62 100%), #006B62;\n  --bp-grad-lime: linear-gradient(110deg, rgba(183,203,51,0.00) 36.06%, rgba(183,203,51,0.25) 97.65%), #FFFFFF;\n  --bp-font: 'Poppins','Segoe UI',Arial,sans-serif;\n  --bp-fs-h1: 44px; --bp-fs-h2: 31px; --bp-fs-h3: 24px; --bp-fs-pre: 15px;\n  --bp-fs-body: 17px; --bp-fs-small: 14px; --bp-fs-foot: 13px; --bp-fs-btn: 17px;\n  --bp-lh-body: 1.75;\n  --bp-s-1: 4px; --bp-s-2: 8px; --bp-s-3: 12px; --bp-s-4: 16px;\n  --bp-s-5: 24px; --bp-s-6: 32px; --bp-s-7: 44px; --bp-s-8: 72px;\n  --bp-measure: 760px; --bp-side: 40px;\n  --bp-radius-photo: 16px; --bp-radius-btn: 10px; --bp-radius-card: 20px;\n  --bp-shadow: 0 10px 30px rgba(0,88,89,0.10);\n  font-family: var(--bp-font);\n  font-size: var(--bp-fs-body);\n  line-height: var(--bp-lh-body);\n  color: var(--bp-ink);\n  background: var(--bp-white);\n  -webkit-font-smoothing: antialiased;\n}\n.bp-adv, .bp-adv * { box-sizing: border-box; }\n.bp-adv p, .bp-adv li, .bp-adv h1, .bp-adv h2, .bp-adv h3, .bp-adv blockquote,\n.bp-adv a, .bp-adv cite, .bp-adv span { overflow-wrap: break-word; min-width: 0; }\n\n\/* THE TOGGLE. One word in the block's own \"Additional CSS class(es)\" field\n   hides an optional component on the front end without deleting anything. *\/\n.bp-adv .bp-off { display: none !important; }\n\n\/* the page opens on green, never on grey (his point 1) *\/\n.bp-adv .bp-adv-rule {\n  height: 6px; border: 0; margin-block: 0; max-width: none;\n  background: linear-gradient(90deg, #005859 0%, #006B62 38%, #228A62 66%, #B7CB33 100%);\n}\n\n\/* --- section surfaces ------------------------------------------------------ *\/\n.bp-adv-sec { position: relative; background: var(--bp-white);\n  padding: var(--bp-s-8) var(--bp-side); margin-block: 0; }\n\/* the measure: every direct child of a section is the 760px text column *\/\n.bp-adv-sec > * { max-width: var(--bp-measure); margin-inline: auto; }\n.bp-adv-sec > *:last-child { margin-block-end: 0; }\n.bp-adv-sec--wash  { background: linear-gradient(180deg, #B7CB331F 0%, #B7CB3312 100%), #FFFFFF; }\n.bp-adv-sec--dark  { background: var(--bp-grad-dark); color: var(--bp-white); }\n.bp-adv-sec--dark p, .bp-adv-sec--dark cite, .bp-adv-sec--dark li { color: var(--bp-white); }\n.bp-adv-sec--offer { background: var(--bp-grad-lime); text-align: center; }\n.bp-adv-sec--hero  { padding-block-start: var(--bp-s-6); }\n.bp-adv-sec--disclosure { padding-block: var(--bp-s-6);\n  border-top: 1px solid var(--bp-sand); }\n\n\/* --- the side accent bar, his own example (\"a colour block on the left or the\n       right side of a section\"), design rev 3: a slim vertical bar hugging the\n       text column rather than a wide margin panel. Below 1100px the margin is\n       gone, so it becomes a slim top edge. ---------------------------------- *\/\n.bp-adv-rail { overflow: hidden; }\n.bp-adv-rail::before {\n  content: \"\"; position: absolute; top: var(--bp-s-7); bottom: var(--bp-s-7);\n  width: 6px; border-radius: 3px;\n  background: linear-gradient(180deg, var(--bp-forest) 0%, var(--bp-lime) 100%);\n}\n.bp-adv-rail--left::before  { left: calc((100% - var(--bp-measure)) \/ 2 - 34px); }\n.bp-adv-rail--right::before { right: calc((100% - var(--bp-measure)) \/ 2 - 34px); }\n@media (max-width: 1099px) {\n  .bp-adv-rail::before { left: 0; right: 0; width: auto; bottom: auto; top: 0;\n    height: 4px; border-radius: 0; background: var(--bp-lime); }\n}\n\n\/* --- CORE BLOCKS, styled by element. This is the part that makes an inserted\n       block come out on-design with no class. --------------------------------- *\/\n.bp-adv p { font-size: var(--bp-fs-body); line-height: var(--bp-lh-body);\n  margin-block: 0 var(--bp-s-5); }\n.bp-adv h1 { font-size: var(--bp-fs-h1); font-weight: 700; line-height: 1.22;\n  margin-block: 0 var(--bp-s-4); }\n\/* an H2 is its own colour band, so the page can be read from the headings\n   alone (his point 3). Dark green on light sections, light green on the dark\n   one, so a heading always wins against its own background. *\/\n.bp-adv h2 {\n  font-size: var(--bp-fs-h2); font-weight: 700; line-height: 1.28;\n  margin-block: 0 var(--bp-s-5);\n  background: var(--bp-grad-dark); color: var(--bp-white);\n  padding: var(--bp-s-4) var(--bp-s-5);\n  border-radius: var(--bp-radius-btn);\n  border-left: 6px solid var(--bp-lime);\n}\n.bp-adv-sec--dark h2 { background: var(--bp-lime); color: var(--bp-ink);\n  border-left-color: var(--bp-forest); }\n\/* H3: same background as its section, bigger font (his point 3, verbatim) *\/\n.bp-adv h3 { font-size: var(--bp-fs-h3); font-weight: 700; line-height: 1.35;\n  color: var(--bp-forest); background: transparent; margin-block: 0 var(--bp-s-3); }\n.bp-adv-sec--dark h3 { color: var(--bp-lime); }\n.bp-adv ul, .bp-adv ol { font-size: var(--bp-fs-body); line-height: var(--bp-lh-body);\n  margin-block: 0 var(--bp-s-5); padding-left: var(--bp-s-5); }\n.bp-adv li { margin-block-end: var(--bp-s-2); }\n.bp-adv a { color: var(--bp-teal); text-decoration: underline; }\n.bp-adv a:hover { color: var(--bp-olive); }\n.bp-adv-sec--dark a, .bp-adv-sec--dark strong { color: var(--bp-lime); }\n.bp-adv strong { font-weight: 700; }\n\/* the highlight pill. Colours ride on the inline style core writes, so only\n   the shape lives here and any <mark> in the article picks it up. *\/\n.bp-adv mark {\n  padding: 0 10px; border-radius: 10px; display: inline;\n  -webkit-box-decoration-break: clone; box-decoration-break: clone;\n}\n\/* figures match the approved page exactly: card radius plus the soft shadow,\n   and a left-aligned caption rather than core's centred one *\/\n.bp-adv .wp-block-image { margin-block: var(--bp-s-5); margin-inline: auto; }\n.bp-adv .wp-block-image img { display: block; width: 100%; height: auto;\n  border-radius: var(--bp-radius-card); box-shadow: var(--bp-shadow); }\n.bp-adv .wp-block-image figcaption { font-size: var(--bp-fs-foot); line-height: 1.55;\n  color: var(--bp-foot); text-align: left; margin-block: var(--bp-s-2) 0; }\n.bp-adv .wp-block-embed, .bp-adv .wp-block-video { margin-block: var(--bp-s-5); }\n.bp-adv .wp-block-embed iframe, .bp-adv .wp-block-video video {\n  width: 100%; border-radius: var(--bp-radius-photo); }\n.bp-adv .wp-block-separator:not(.bp-adv-rule) { border: 0; border-top: 1px solid var(--bp-sand);\n  margin-block: var(--bp-s-5); }\n\n\/* quotes: core pullquote and core quote both land on the lime rule. The\n   font-size reset undoes core's own 1.5em on the figure, which would otherwise\n   leak into anything inside the quote that has no size of its own. *\/\n\/* margin-inline is load bearing, and it must be `auto` rather than `0`.\n   `blockquote` and `figure` carry a 40px side margin in the browser's own\n   default stylesheet, which indents the quote inside its rule and makes the\n   copy wrap early on a phone. But these blocks are direct children of a\n   section, so zeroing the side margin also defeats the measure rule\n   `.bp-adv-sec > * { margin-inline: auto }` and pins them to the left edge. *\/\n.bp-adv .wp-block-pullquote, .bp-adv .wp-block-quote {\n  border: 0; border-left: 5px solid var(--bp-lime); background: transparent;\n  padding: var(--bp-s-2) 0 var(--bp-s-2) var(--bp-s-5);\n  margin-block: var(--bp-s-5); margin-inline: auto;\n  text-align: left; font-size: var(--bp-fs-body);\n}\n.bp-adv .wp-block-pullquote blockquote { border: 0; margin: 0; padding: 0; }\n.bp-adv .wp-block-pullquote p, .bp-adv .wp-block-quote p {\n  font-size: 24px; line-height: 1.45; font-weight: 600;\n  margin-block: 0 var(--bp-s-2); color: var(--bp-forest); }\n.bp-adv .wp-block-pullquote cite, .bp-adv .wp-block-quote cite {\n  display: block; margin: 0; font-size: var(--bp-fs-small); color: var(--bp-foot);\n  font-style: normal; text-transform: none; }\n\n\/* buttons: two classes so core's own .wp-block-button__link cannot win *\/\n.bp-adv .wp-block-buttons { display: flex; justify-content: center;\n  margin-block: 0 var(--bp-s-4); }\n.bp-adv .wp-block-button__link {\n  display: inline-flex; align-items: center; justify-content: center; min-height: 48px;\n  background: var(--bp-teal); color: var(--bp-white); font-size: var(--bp-fs-btn);\n  font-weight: 700; line-height: 1.2; border-radius: var(--bp-radius-btn);\n  padding: 15px 44px; text-decoration: none; transition: background 250ms ease;\n  box-shadow: var(--bp-shadow);\n}\n.bp-adv .wp-block-button__link:hover { background: var(--bp-olive); color: var(--bp-white); }\n\n\/* --- slot 1: pre-headline, headline, sub-headline (Jesse's headline skill) --- *\/\n.bp-adv .bp-adv-preheadline {\n  color: var(--bp-forest); font-size: var(--bp-fs-pre); font-weight: 600; line-height: 1.5;\n  border-left: 4px solid var(--bp-lime); padding-left: var(--bp-s-3);\n  margin-block: 0 var(--bp-s-4);\n}\n.bp-adv .bp-adv-subheadline { font-size: 21px; line-height: 1.5; font-weight: 600;\n  color: var(--bp-forest); margin-block: 0 var(--bp-s-5); }\n.bp-adv .bp-adv-standfirst { font-size: 19px; line-height: 1.65;\n  margin-block: 0 var(--bp-s-5); }\n.bp-adv .bp-adv-lede { font-size: 18px; line-height: 1.7;\n  margin-block: 0 var(--bp-s-5); }\n.bp-adv .bp-adv-byline { font-size: var(--bp-fs-small); color: var(--bp-foot);\n  line-height: 1.6; margin-block: 0 var(--bp-s-5); }\n.bp-adv .bp-adv-socialproof { font-size: var(--bp-fs-small); color: var(--bp-foot);\n  margin-block: 0 var(--bp-s-5); }\n\/* the offer headline above the CTA. Jesse asked for a second H1 here; the brand\n   doc's accessibility rule is one h1 per page, so it is rendered at H1 size and\n   stays an h2 element. Named in the close as the one design conflict. *\/\n.bp-adv h2.bp-adv-offerhead {\n  font-size: var(--bp-fs-h1); font-weight: 700; line-height: 1.22;\n  margin-block: 0 var(--bp-s-4); text-align: center; color: var(--bp-ink);\n  background: none; padding: 0; border: 0; border-radius: 0;\n}\n\n\/* --- Written by + Verified by. The avatar is the first child and spans the\n       three text rows, so the whole box is four ordinary paragraphs and stays\n       editable without nested columns. ---------------------------------------- *\/\n.bp-adv .bp-adv-authors {\n  background: var(--bp-white); border: 1px solid var(--bp-sand);\n  border-top: 4px solid var(--bp-lime); border-radius: var(--bp-radius-card);\n  box-shadow: var(--bp-shadow); padding: var(--bp-s-5);\n  margin-block: 0 var(--bp-s-4);\n  \/* auto-fit, so switching the verified box off leaves one full-width author\n     rather than a half-empty card *\/\n  display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));\n  gap: var(--bp-s-5); align-items: start;\n}\n.bp-adv .bp-adv-author {\n  display: grid; grid-template-columns: 62px 1fr; gap: 0 var(--bp-s-3);\n  align-items: start; min-width: 0;\n}\n.bp-adv .bp-adv-avatar {\n  grid-row: 1 \/ span 3; width: 62px; height: 62px; border-radius: 50%;\n  background: #B7CB331F; border: 2px dashed var(--bp-olive);\n  display: flex; align-items: center; justify-content: center;\n  font-size: 10px; font-weight: 700; letter-spacing: 0.06em; color: var(--bp-forest);\n  margin-block: 0;\n}\n.bp-adv .bp-adv-author.is-placeholder .bp-adv-avatar {\n  border-color: var(--bp-sand); background: #fff; color: var(--bp-foot); }\n.bp-adv .bp-adv-author-role {\n  font-size: 11px; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase;\n  color: var(--bp-forest); line-height: 1.6; margin-block: 0; }\n.bp-adv .bp-adv-author.is-placeholder .bp-adv-author-role { color: var(--bp-foot); }\n.bp-adv .bp-adv-author-name { font-size: 17px; font-weight: 700; line-height: 1.35;\n  margin-block: 0; }\n.bp-adv .bp-adv-author-cred { font-size: var(--bp-fs-foot); color: var(--bp-foot);\n  line-height: 1.55; margin-block: 0; }\n\/* the optional wrapper must not break the two-column grid of the box *\/\n.bp-adv .bp-adv-authors > .bp-optional { display: contents; }\n.bp-adv .bp-adv-authors > .bp-optional.bp-off { display: none !important; }\n\n\/* --- placeholders: image slot, video slot ---------------------------------- *\/\n.bp-adv .bp-slot {\n  display: flex; align-items: center; justify-content: center; text-align: center;\n  min-height: 180px; padding: var(--bp-s-4); margin-block: var(--bp-s-5) 0;\n  border: 2px dashed var(--bp-olive); border-radius: var(--bp-radius-photo);\n  background: #B7CB331F; color: var(--bp-forest);\n}\n.bp-adv .bp-slot p { font-size: var(--bp-fs-small); font-weight: 700; margin-block: 0; }\n.bp-adv .bp-slot--video { min-height: 260px; }\n\n\/* --- mid-article CTA band --------------------------------------------------- *\/\n.bp-adv .bp-adv-midcta {\n  background: var(--bp-grad-lime); border: 1px solid var(--bp-lime);\n  border-radius: var(--bp-radius-card); padding: var(--bp-s-5) var(--bp-s-4);\n  margin-block: var(--bp-s-6); text-align: center;\n}\n.bp-adv .bp-adv-midcta .wp-block-buttons { margin-block-end: var(--bp-s-2); }\n.bp-adv .bp-adv-midcta .bp-adv-foot { margin-block: 0; }\n\n\/* the closing CTA is one named unit in List View, so it moves and toggles as a\n   whole. It carries no box of its own: the spacing must read exactly as it does\n   on the approved page, where the three parts are plain siblings. *\/\n.bp-adv .bp-adv-ctablock { margin-block: 0 var(--bp-s-5); }\n.bp-adv .bp-adv-ctablock .wp-block-buttons { margin-block-end: var(--bp-s-4); }\n.bp-adv .bp-adv-ctablock .bp-adv-foot { margin-block: 0; }\n\n\/* --- the condition, slot 8: the results page reference-card shape ----------- *\/\n.bp-adv .bp-adv-condition {\n  background: var(--bp-white); border: 1px solid var(--bp-sand);\n  border-left: 5px solid var(--bp-lime); border-radius: var(--bp-radius-btn);\n  padding: var(--bp-s-4) var(--bp-s-5); font-weight: 600; box-shadow: var(--bp-shadow);\n}\n\n\/* --- the numbers card: the results page focus panel, same gradient, same\n       radius, same lime figures (\"use more of that design\") ------------------ *\/\n.bp-adv .bp-adv-numcard {\n  background: linear-gradient(135deg, var(--bp-teal) 0%, var(--bp-forest) 100%);\n  border-radius: var(--bp-radius-card);\n  padding: var(--bp-s-6) var(--bp-s-5) var(--bp-s-5);\n  box-shadow: var(--bp-shadow); margin-block: var(--bp-s-5) 0;\n  position: relative; overflow: hidden;\n}\n.bp-adv .bp-adv-numcard::after {\n  content: \"\"; position: absolute; right: -70px; top: -70px; width: 240px; height: 240px;\n  border-radius: 50%; background: rgba(255,255,255,0.05); pointer-events: none;\n}\n.bp-adv .bp-adv-numcard .wp-block-columns {\n  position: relative; z-index: 1; gap: var(--bp-s-5); margin-block: 0; }\n.bp-adv .bp-adv-numcard .wp-block-column { min-width: 0; }\n.bp-adv .bp-adv-num-v { font-size: 44px; font-weight: 700; line-height: 1.12;\n  color: var(--bp-lime); text-align: center; margin-block: 0 var(--bp-s-2); }\n.bp-adv .bp-adv-num-l { font-size: var(--bp-fs-small); line-height: 1.5;\n  color: rgba(255,255,255,0.92); text-align: center; margin-block: 0; }\n.bp-adv .bp-adv-numsrc { margin-block: var(--bp-s-5) 0; }\n\n\/* --- the proof slot: a dashed card until a consented quote exists. 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Biomarkers of Nutrition for Development (BOND): Vitamin B-12 Review. J Nutr. 2018;148(suppl_4):1995S-2027S.\",\"url\":\"https:\/\/pubmed.ncbi.nlm.nih.gov\/30500928\/\"},{\"@type\":\"CreativeWork\",\"name\":\"Labplusarts, het laboratorium waarmee BioProfile werkt: referentiewaarde bij de bepaling vitamine b12 (VB12), 148 tot 584 pmol\/l. Lijst van 24 september 2026.\"},{\"@type\":\"CreativeWork\",\"name\":\"BioProfile, de pakketten van het bloedonderzoek en de waarden in elk pakket.\",\"url\":\"https:\/\/bioprofile.com\/bloedonderzoek\/\"}]},{\"@type\":\"MedicalTest\",\"@id\":\"https:\/\/bioprofile.com\/biomarkers\/vitamine-b12\/#biomarker\",\"name\":\"Vitamine B12\",\"alternateName\":[\"Vitamin B12\"]}]}<\/script>\n\n\n\n<section class=\"wp-block-group bp-adv bp-biomarker bp-biomarker--page is-layout-flow wp-block-group-is-layout-flow\">\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity bp-adv-rule\"\/>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--hero is-layout-flow wp-block-group-is-layout-flow\">\n\n<p class=\"bp-bm-crumbs wp-block-paragraph\"><a href=\"https:\/\/bioprofile.com\/en\/\">Home<\/a> \u203a <a href=\"https:\/\/bioprofile.com\/en\/biomarkers\/\">Biomarkers<\/a> \u203a <span>Vitamin B12<\/span><\/p>\n\n\n\n<h1 class=\"wp-block-heading bp-adv-h1\">Vitamin B12: what your level tells you<\/h1>\n\n\n\n<p class=\"bp-adv-standfirst wp-block-paragraph\">In a large Danish study, a vitamin B12 level of 200 to 600 pmol\/l was taken as the reference range for the general population.<sup>[1]<\/sup><\/p>\n\n\n\n<p class=\"bp-adv-lede wp-block-paragraph\">On this page, you can read what vitamin B12 is, what the guidelines say about a level that is too low or too high, what affects your level and which other values are best to look at alongside it.<\/p>\n\n\n\n<p class=\"bp-bm-names wp-block-paragraph\">Also known as: cobalamin. At the lab: VB12.<\/p>\n\n\n\n<p class=\"bp-adv-byline wp-block-paragraph\">Updated on 2 October 2026<\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--wash is-layout-flow wp-block-group-is-layout-flow\">\n\n<div class=\"wp-block-group bp-bm-toc is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-inhoud\">On this page<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li><a href=\"#bp-in-het-kort\">In short<\/a><\/li>\n\n\n<li><a href=\"#bp-wat-is-vitamine-b12\">What is vitamin B12?<\/a><\/li>\n\n\n<li><a href=\"#bp-waarom-het-ertoe-doet\">Why this vitamin matters<\/a><\/li>\n\n\n<li><a href=\"#bp-wat-je-waarde-zegt\">What your vitamin B12 level tells you<\/a><\/li>\n\n\n<li><a href=\"#bp-wat-het-beinvloedt\">What affects your vitamin B12<\/a><\/li>\n\n\n<li><a href=\"#bp-welke-pakketten\">Which BioProfile packages measure vitamin B12<\/a><\/li>\n\n\n<li><a href=\"#bp-waarden-die-erbij-horen\">Related values<\/a><\/li>\n\n\n<li><a href=\"#bp-hoe-gemaakt\">How this page was made<\/a><\/li>\n\n\n<li><a href=\"#bp-bronnen\">Sources<\/a><\/li>\n\n<\/ul>\n\n<\/div>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-in-het-kort\">In short<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li>A vitamin B12 deficiency can cause symptoms such as tiredness, heart palpitations or memory loss.<sup>[2]<\/sup><\/li>\n\n\n<li>A deficiency is rare, but low status is often seen in groups who eat few animal products.<sup>[2, 3]<\/sup><\/li>\n\n\n<li>According to a Danish study, a high level may point to a hidden serious condition.<sup>[1]<\/sup><\/li>\n\n\n<li>According to the Voedingscentrum, many people do not need a supplement, but for vegans the advice is to take one.<sup>[2]<\/sup><\/li>\n\n<\/ul>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--wash is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-wat-is-vitamine-b12\">What is vitamin B12?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Vitamin B12 is a vitamin your body needs to make red blood cells. Red blood cells carry oxygen through your blood. Vitamin B12 is also important for your nervous system to work properly. You get it from animal products, such as milk, meat, fish and eggs.<sup>[2, 3]<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Your body stores vitamin B12 as a reserve, mainly in the liver. A deficiency can lead to a form of anaemia, which can make you feel tired or dizzy, for example. A deficiency can also affect your nerves, for instance with tingling in your fingers. Because your body uses up its reserve first, you often only notice a deficiency after a few months or even a year.<sup>[2, 3]<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The lab measures the vitamin B12 in your blood. A blood test like this can show whether you have too little vitamin B12. According to research, too little vitamin B12 is often seen in people who eat few animal products. So a low level can point to a deficiency.<sup>[2, 3]<\/sup><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-waarom-het-ertoe-doet\">Why this vitamin matters<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Vitamin B12 is the only water-soluble vitamin that your body keeps in store. The store holds around 2 to 5 milligrams. This is one reason why a deficiency is rare.<sup>[2]<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a long time, the focus was mainly on clear symptoms caused by a deficiency. According to an expert review, there is now more attention for low status in groups who eat few animal products. This can be seen in a blood level. What the effects of such low status are still needs to be worked out.<sup>[3]<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">According to the Voedingscentrum, adults aged 18 and over need 2.8 micrograms of vitamin B12 a day. If you are pregnant, that is 3.3 micrograms. If you get a little less, that does not mean you have a deficiency straight away. For most people, the recommendation is higher than what they actually need.<sup>[2]<\/sup><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--wash is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-wat-je-waarde-zegt\">What your vitamin B12 level tells you<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">The lab's reference range<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Labplusarts, the lab BioProfile works with, uses a reference value of 148 to 584 pmol\/l for vitamin B12. The lab calls a level between these limits normal.<sup>[4]<\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">The study by Arendt and colleagues<\/h3>\n\n\n\n<figure class=\"wp-block-table bp-bm-table\"><table><thead><tr><th>Value<\/th><th>What it can mean<\/th><th>Who it is for<\/th><\/tr><\/thead><tbody><tr><td>200 to 600 pmol\/l<sup>[1]<\/sup><\/td><td>The reference range for the general population, used for comparison in the study<\/td><td>The general population, as the reference in the study<\/td><\/tr><tr><td>601 to 800 pmol\/l<sup>[1]<\/sup><\/td><td>Higher than the reference range; in this group, the chance of a blood clot in a vein was greater<\/td><td>People with a serious condition, measured before it was diagnosed<\/td><\/tr><tr><td>Above 800 pmol\/l<sup>[1]<\/sup><\/td><td>Higher than the reference range; in this group too, the chance of a blood clot in a vein was greater<\/td><td>People with a serious condition, measured before it was diagnosed<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"bp-bm-caption wp-block-paragraph\">Source: Arendt and colleagues, Thrombosis Research. A Danish population study of people with a serious condition, whose vitamin B12 was measured before that condition was diagnosed. These limits apply to that study.<sup>[1]<\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Vitamin B12 too low<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A level that is too low can point to a deficiency. According to the Voedingscentrum, a deficiency leads to a form of anaemia called macrocytic anaemia. Besides tiredness and dizziness, this can also give you heart palpitations or ringing in your ears. A deficiency can also cause memory loss, problems with your coordination and muscle weakness in your legs.<sup>[2]<\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Vitamin B12 too high<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">According to a Danish study, a high level in the blood may point to a hidden serious condition. In that study, people with a higher level also had a greater chance of a blood clot in a vein. According to the researchers, what this means in practice still needs further research.<sup>[1]<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.<\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-wat-het-beinvloedt\">What affects your vitamin B12<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">What you eat<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Vitamin B12 is found almost only in animal products, because bacteria in the digestive tract of animals make it. A 100 gram portion of cooked salmon contains 4.0 micrograms, and a 50 gram egg contains 0.8 micrograms. Dried seaweed and algae also contain vitamin B12, but mostly in a form that is not active and that your body does not absorb well.<sup>[2]<\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Eating without animal products<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">If you don't eat animal products, a deficiency can develop. According to an expert review, clear symptoms of a deficiency are mainly caused by a particular form of anaemia or by a strictly vegetarian diet. For vegans, the Voedingscentrum recommends products with added vitamin B12, as well as a supplement.<sup>[2, 3]<\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How your body absorbs it<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">In your food, vitamin B12 is bound to a protein. Stomach acid releases it. In the small intestine, it binds to another protein from the stomach, called Intrinsic Factor. Your body needs this pairing to absorb it. Your body probably absorbs around 40 to 50% of the vitamin B12 you take in.<sup>[2]<\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Supplements<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">According to the Voedingscentrum, many people do not need a vitamin B12 supplement; it brings no extra health benefit. If you would still like to take one, the advice for adults is no more than 2.8 micrograms a day from a supplement. If you take all your vitamin B12 at the same time, your body absorbs it less efficiently.<sup>[2]<\/sup><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--wash is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-welke-pakketten\">Which BioProfile packages measure vitamin B12<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Vitamin B12 is included in BioProfile 121 and 150.<sup>[5]<\/sup><\/p>\n\n\n\n<div class=\"wp-block-buttons is-content-justification-center is-layout-flex wp-container-core-buttons-is-layout-3e41869c wp-block-buttons-is-layout-flex\">\n\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/bioprofile.com\/en\/blood-testing\/\">View the packages<\/a><\/div>\n\n<\/div>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-waarden-die-erbij-horen\">Values that go with it<\/h2>\n\n\n\n<ul class=\"wp-block-list bp-bm-related\">\n\n<li><a href=\"https:\/\/bioprofile.com\/en\/biomarkers\/hemoglobin\/\">Hemoglobin<\/a>: helps to show whether you have anaemia, and a vitamin B12 deficiency can lead to a form of anaemia.<sup>[2]<\/sup><\/li>\n\n\n<li><a href=\"https:\/\/bioprofile.com\/en\/biomarkers\/white-blood-cells\/\">White blood cells<\/a>: complete the picture of your blood alongside the values for your red blood cells.<\/li>\n\n\n<li><a href=\"https:\/\/bioprofile.com\/en\/biomarkers\/red-blood-cells\/\">Red blood cells<\/a>: these are your red blood cells, and your body needs vitamin B12 to make them.<sup>[2]<\/sup><\/li>\n\n\n<li><a href=\"https:\/\/bioprofile.com\/en\/biomarkers\/platelets\/\">Platelets<\/a>: together with the other blood cells, they complete your full blood count.<\/li>\n\n\n<li><a href=\"https:\/\/bioprofile.com\/en\/biomarkers\/hematocrit\/\">Hematocrit<\/a>: this is one of the values for your red blood cells, so it fits into the same picture.<\/li>\n\n<\/ul>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--wash is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-hoe-gemaakt\">How this page was made<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The BioProfile editorial team wrote this page on 2 October 2026 from the sources below, which we read on 2 October 2026. Every number on this page appears in one of those sources, with that source's number next to it. An expert has yet to check this page; once checked, the expert's name and the date of the check will appear at the top. This page offers explanation, not a diagnosis. Discuss an abnormal value with your GP.<\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-adv-sec bp-adv-sec--disclosure is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bp-bronnen\">Sources<\/h2>\n\n\n\n<ol class=\"wp-block-list bp-adv-srclist bp-bm-src\">\n\n<li>Arendt JFH, Farkas DK, Pedersen L, et al. Elevated plasma vitamin B12 levels and risk of venous thromboembolism among cancer patients: A population-based cohort study. Thromb Res. 2017;156:177-183. <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/28667844\/\" target=\"_blank\" rel=\"noopener\">https:\/\/pubmed.ncbi.nlm.nih.gov\/28667844\/<\/a><\/li>\n\n\n<li>Voedingscentrum. Vitamine B12. Accessed on 12 October 2026. <a href=\"https:\/\/www.voedingscentrum.nl\/encyclopedie\/vitamine-b12.aspx\" target=\"_blank\" rel=\"noopener\">https:\/\/www.voedingscentrum.nl\/encyclopedie\/vitamine-b12.aspx<\/a><\/li>\n\n\n<li>Allen LH, Miller JW, de Groot L, et al. Biomarkers of Nutrition for Development (BOND): Vitamin B-12 Review. J Nutr. 2018;148(suppl_4):1995S-2027S. <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/30500928\/\" target=\"_blank\" rel=\"noopener\">https:\/\/pubmed.ncbi.nlm.nih.gov\/30500928\/<\/a><\/li>\n\n\n<li>Labplusarts, the laboratory BioProfile works with: reference value for the vitamin B12 test (VB12), 148 to 584 pmol\/l. List dated 24 September 2026.<\/li>\n\n\n<li>BioProfile, the blood test packages and the values in each package. <a href=\"https:\/\/bioprofile.com\/en\/blood-testing\/\" target=\"_blank\" rel=\"noopener\">https:\/\/bioprofile.com\/en\/blood-testing\/<\/a><\/li>\n\n<\/ol>\n\n<\/div>\n\n<\/section>\n\n","protected":false},"excerpt":{"rendered":"<p>Home \u203a Biomarkers \u203a Vitamin B12 Vitamin B12: what your level tells you In a large Danish study, a vitamin B12 level of 200 to 600 pmol\/l was taken as the reference range for the general population.[1] On this page, you can read what vitamin B12 is, what the guidelines say about a level that [&hellip;]<\/p>\n","protected":false},"author":18,"featured_media":0,"parent":6592,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"elementor_header_footer","meta":{"_yoast_wpseo_title":"Vitamin B12: what your level tells you | BioProfile","_yoast_wpseo_metadesc":"What vitamin B12 does, what a level that is too low or too high can point to, and what affects your level. 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