{"id":8006,"date":"2026-10-08T09:20:00","date_gmt":"2026-10-08T09:20:00","guid":{"rendered":"https:\/\/bioprofile.com\/?p=8006"},"modified":"2026-10-09T18:03:13","modified_gmt":"2026-10-09T18:03:13","slug":"which-vitamin-for-fatigue","status":"publish","type":"post","link":"https:\/\/bioprofile.com\/en\/which-vitamin-for-fatigue\/","title":{"rendered":"Which vitamin for fatigue: what iron, vitamin D and B12 do and do not explain"},"content":{"rendered":"\n<article class=\"wp-block-group bp-blog is-layout-flow wp-block-group-is-layout-flow\">\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n<link rel=\"stylesheet\" href=\"https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600;700&#038;display=swap\">\n<style id=\"bp-blog-design\">\n.bp-blog {\n  --bp-ink: #212527; --bp-teal: #005859; --bp-teal-deep: #006B62; --bp-emerald: #228A62;\n  --bp-green: #7CA74D; --bp-lime: #B7CB33; --bp-lime-soft: #B7CB3329; --bp-green-aa: #4F6B28;\n  --bp-beige: #EDEAE5; --bp-sand: #DBD4CB; --bp-pale-teal: #D9E6E6; --bp-white: #FFFFFF;\n  --bp-foot: #6b6b6b;\n  --bp-font: 'Poppins','Segoe UI',Arial,sans-serif;\n  --bp-fs-h1: 40px; --bp-fs-h2: 29px; --bp-fs-h3: 21px; --bp-fs-body: 17px;\n  --bp-fs-lead: 19px; --bp-fs-small: 14px; --bp-fs-foot: 13px; --bp-fs-btn: 17px;\n  --bp-lh-body: 1.75;\n  --bp-s-2: 8px; --bp-s-3: 12px; --bp-s-4: 16px; --bp-s-5: 24px; --bp-s-6: 32px;\n  --bp-s-7: 44px; --bp-s-8: 72px;\n  --bp-measure: 875px; --bp-prose: 875px; --bp-side: 40px; --bp-portrait: 132px;\n  --bp-radius-card: 20px; --bp-radius-btn: 10px; --bp-radius-chip: 999px;\n  --bp-shadow: 0 10px 30px rgba(0,88,89,0.10); --bp-shadow-soft: 0 2px 10px rgba(0,88,89,0.06);\n  font-family: var(--bp-font); font-size: var(--bp-fs-body); line-height: var(--bp-lh-body);\n  color: var(--bp-ink); background: var(--bp-white); -webkit-font-smoothing: antialiased;\n}\n.bp-blog, .bp-blog * { box-sizing: border-box; }\n.bp-blog p, .bp-blog li, .bp-blog h1, .bp-blog h2, .bp-blog h3, .bp-blog a, .bp-blog td,\n.bp-blog th, .bp-blog cite { overflow-wrap: break-word; min-width: 0; }\n.bp-blog h1, .bp-blog h2, .bp-blog h3 { text-wrap: balance; }\n.bp-blog p, .bp-blog li { text-wrap: pretty; }\n\/* WordPress core's flow layout puts 24px above every child after the first; inside\n   a grid or a flex row that is a misalignment (measured on the scan pages 2026-08-21) *\/\n.bp-blog .bp-blog-author > *, .bp-blog .bp-blog-related > *, .bp-blog .bp-blog-verify > * { margin-block: 0; }\n\n\/* --- sections: one column, the article measure, the section rhythm ------------ *\/\n.bp-blog-sec { position: relative; background: var(--bp-white); margin-block: 0;\n  padding-block: var(--bp-s-7);\n  padding-inline: max(var(--bp-side), calc((100% - var(--bp-measure)) \/ 2)); }\n.bp-blog-sec > *:last-child { margin-block-end: 0; }\n.bp-blog-sec > p, .bp-blog-sec > ul, .bp-blog-sec > ol, .bp-blog-sec > .wp-block-quote,\n.bp-blog-sec > .bp-blog-faq-item, .bp-blog-sec > .bp-blog-takeaways, .bp-blog-sec > .bp-blog-toc,\n.bp-blog-sec > .bp-blog-refs, .bp-blog-sec > .bp-blog-srclead { max-width: var(--bp-prose); }\n.bp-blog-sec--head { padding-block: var(--bp-s-7) 0; }\n.bp-blog-sec--body { padding-block: var(--bp-s-6) var(--bp-s-7); }\n.bp-blog-sec--beige { background: var(--bp-beige); }\n.bp-blog-sec--wash { background: linear-gradient(180deg, #B7CB331A 0%, #B7CB330D 100%), #FFFFFF; }\n.bp-blog-sec--tight { padding-block: var(--bp-s-6); }\n\/* A COLOURED SECTION IS A PANEL, so it carries the panel radius. Measured on the\n   live site 2026-08-28 rather than chosen: bioprofile.com's own coloured blocks\n   come in two families, full-bleed strips (w=1440 edge to edge, radius 0, 40px\n   side padding) and inset panels (the lime block w=677 and the sand block w=576,\n   both radius 16px). Ours cannot be the first: the theme's content wrapper is\n   1140px, so a coloured section here stops 150px short of the screen on both\n   sides and reads as an inset panel with square corners, which is the thing the\n   operator saw. So it takes the panel treatment. The radius is this template's\n   own --bp-radius-card (20px, shared with the scan pages) rather than the site's\n   16px, so the page carries ONE panel radius instead of a third value.\n   The small vertical margin is what lets the corners read where two coloured\n   panels stack (the CTA, the FAQ wash and the sources beige run consecutively). *\/\n.bp-blog .bp-blog-sec--beige, .bp-blog .bp-blog-sec--wash, .bp-blog .bp-blog-cta {\n  border-radius: var(--bp-radius-card); margin-block: var(--bp-s-3); }\n.bp-blog-sec--foot { padding-block: var(--bp-s-5) var(--bp-s-7); border-top: 1px solid var(--bp-sand); }\n.bp-blog .bp-blog-rule { 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\/* --- core blocks by element ------------------------------------------------- *\/\n.bp-blog p { font-size: var(--bp-fs-body); line-height: var(--bp-lh-body); margin-block: 0 var(--bp-s-5); }\n.bp-blog h1 { font-size: var(--bp-fs-h1); font-weight: 700; line-height: 1.22; letter-spacing: -0.01em;\n  margin-block: 0 var(--bp-s-4); color: var(--bp-ink); max-width: var(--bp-measure); }\n.bp-blog h2 { font-size: var(--bp-fs-h2); font-weight: 700; line-height: 1.3; letter-spacing: -0.01em;\n  color: var(--bp-ink); margin-block: var(--bp-s-4) var(--bp-s-4); padding-block-start: var(--bp-s-4);\n  position: relative; max-width: var(--bp-prose); }\n.bp-blog h2::before { content: \"\"; position: absolute; top: 0; left: 0; width: 56px; height: 4px;\n  border-radius: 2px; background: var(--bp-lime); }\n.bp-blog h3 { font-size: var(--bp-fs-h3); font-weight: 700; line-height: 1.35; color: var(--bp-teal);\n  margin-block: var(--bp-s-2) var(--bp-s-3); max-width: var(--bp-prose); }\n.bp-blog ul, .bp-blog 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-blog li { margin-block-end: var(--bp-s-2); }\n.bp-blog a { color: var(--bp-teal); text-decoration: underline; text-underline-offset: 2px; }\n.bp-blog a:hover { color: var(--bp-green); }\n.bp-blog strong { font-weight: 600; }\n.bp-blog .wp-block-quote { border-left: 4px solid var(--bp-lime); margin: 0 0 var(--bp-s-5);\n  padding: var(--bp-s-2) 0 var(--bp-s-2) var(--bp-s-5); font-style: normal; }\n.bp-blog .wp-block-quote p { margin-block: 0 var(--bp-s-2); }\n.bp-blog .wp-block-quote cite { font-size: var(--bp-fs-small); color: var(--bp-foot); font-style: normal; }\n.bp-blog .wp-block-table { margin: 0 0 var(--bp-s-5); overflow-x: auto; }\n.bp-blog .wp-block-table table { border-collapse: collapse; width: 100%; font-size: var(--bp-fs-small); }\n.bp-blog .wp-block-table th, .bp-blog .wp-block-table td { border: 1px solid var(--bp-sand);\n  padding: var(--bp-s-2) var(--bp-s-3); text-align: left; vertical-align: top; }\n.bp-blog .wp-block-table th { background: var(--bp-beige); font-weight: 600; }\n.bp-blog .wp-block-image { margin: 0 0 var(--bp-s-5); }\n.bp-blog .wp-block-image img { display: block; width: 100%; height: auto;\n  border-radius: var(--bp-radius-card); box-shadow: var(--bp-shadow); }\n.bp-blog .wp-block-image figcaption { font-size: var(--bp-fs-foot); line-height: 1.6; color: var(--bp-foot);\n  text-align: left; margin-block: var(--bp-s-2) 0; }\n.bp-blog .wp-block-separator { border: 0; border-top: 1px solid var(--bp-sand); margin-block: var(--bp-s-6); }\n\n\/* --- buttons: two classes so core's own rule cannot win ------------------------ *\/\n.bp-blog .wp-block-buttons { display: flex; justify-content: flex-start; margin-block: 0 var(--bp-s-3); }\n.bp-blog .wp-block-button__link { display: inline-flex; align-items: center; justify-content: center;\n  min-height: 52px; 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); padding: 15px 40px;\n  text-decoration: none; transition: background 250ms ease; box-shadow: var(--bp-shadow); }\n.bp-blog .wp-block-button__link:hover { background: var(--bp-green); color: var(--bp-white); }\n\n\/* --- the head: category, title, the meta line, the picture ------------------- *\/\n.bp-blog .bp-blog-eyebrow { font-size: 15px; font-weight: 600; letter-spacing: 0.08em;\n  text-transform: uppercase; margin-block: 0 var(--bp-s-3); }\n.bp-blog .bp-blog-eyebrow a { color: var(--bp-green-aa); text-decoration: none; }\n.bp-blog .bp-blog-eyebrow a:hover { text-decoration: underline; }\n.bp-blog .bp-blog-meta { font-size: var(--bp-fs-small); line-height: 1.6; color: var(--bp-foot);\n  margin-block: 0 var(--bp-s-5); max-width: var(--bp-measure); }\n.bp-blog .bp-blog-meta a { color: var(--bp-foot); }\n\/* A text link is a thumb target of at least 44px (T332b). 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overflow-wrap: anywhere; }\n\n\/* --- the author card (the scan pages' card, three zones) ------------------------- *\/\n.bp-blog .bp-blog-author { display: grid;\n  grid-template-columns: var(--bp-portrait) minmax(0, 220px) minmax(0, 1fr);\n  grid-template-areas: \"photo id bio\" \"meta meta meta\"; gap: var(--bp-s-5) var(--bp-s-6);\n  align-items: start; background: var(--bp-white); border: 1px solid var(--bp-sand);\n  border-radius: var(--bp-radius-card); box-shadow: var(--bp-shadow-soft);\n  padding: var(--bp-s-5); margin-block: 0 var(--bp-s-4); max-width: none; }\n.bp-blog .bp-blog-author > .wp-block-image { grid-area: photo; margin: 0; width: var(--bp-portrait); }\n.bp-blog .bp-blog-author .wp-block-image img { aspect-ratio: 1 \/ 1; object-fit: cover;\n  object-position: 50% 12%; width: var(--bp-portrait); height: var(--bp-portrait); border-radius: 50%;\n  background: var(--bp-pale-teal); border: 2px solid var(--bp-lime); box-shadow: none; }\n.bp-blog .bp-blog-authorid { grid-area: id; 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}\n}\n\n\/* --- verified by: exists only for a real, confirmed verifier ------------------- *\/\n.bp-blog .bp-blog-verify { background: var(--bp-white); border: 1px solid var(--bp-sand);\n  border-radius: var(--bp-radius-card); box-shadow: inset 5px 0 0 var(--bp-lime), var(--bp-shadow-soft);\n  padding: var(--bp-s-4) var(--bp-s-5) var(--bp-s-4) var(--bp-s-6); margin-block: 0 var(--bp-s-4); }\n.bp-blog .bp-blog-verify > * { margin-block: 0 var(--bp-s-2); max-width: none; }\n.bp-blog .bp-blog-verify-name { font-size: 18px; font-weight: 700; }\n.bp-blog .bp-blog-verify-cred { font-size: var(--bp-fs-small); color: var(--bp-foot); }\n\/* T332, Jesse 2026-09-17: a SMALL box at the top, under the introduction *\/\n.bp-blog .bp-blog-verify--top { display: grid; grid-template-columns: 56px 1fr; column-gap: 14px;\n  align-items: center; padding: 12px 16px; margin-block: var(--bp-s-3); max-width: var(--bp-prose); }\n.bp-blog .bp-blog-verify--top > * { margin: 0; }\n.bp-blog .bp-blog-verify--top .wp-block-image { grid-row: span 3; 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That matters, because fatigue comes from many more things than a deficiency. If you are tired and have no other symptoms, a blood test rarely finds a cause.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">4<\/a><\/sup> <a href=\"https:\/\/bioprofile.com\/en\/scan-fatigue-test\/\">The BioProfile energy scan<\/a> measures how much your fatigue bothers you and shows where you stand today. The scan is not a diagnosis. The scan gives you insight to make better choices about your diet and lifestyle. Only a doctor can identify a cause.<\/p>\n\n\n\n<div class=\"wp-block-group bp-blog-byline bp-blog-byline--photo is-layout-flow wp-block-group-is-layout-flow\">\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" width=\"650\" height=\"812\" src=\"https:\/\/bioprofile.com\/wp-content\/uploads\/2026\/09\/rt-portret-adil-maqbool.webp\" alt=\"Portrait of Adil Maqbool\" class=\"wp-image-5977\" srcset=\"https:\/\/bioprofile.com\/wp-content\/uploads\/2026\/09\/rt-portret-adil-maqbool.webp 650w, https:\/\/bioprofile.com\/wp-content\/uploads\/2026\/09\/rt-portret-adil-maqbool-240x300.webp 240w\" sizes=\"(max-width: 650px) 100vw, 650px\" \/><\/figure>\n\n\n\n<p class=\"bp-blog-byline-name wp-block-paragraph\">Written by <strong>Adil Maqbool, MBBS, MRCP<\/strong><\/p>\n\n\n\n<p class=\"bp-blog-byline-cred wp-block-paragraph\">Doctor, graduated from the University of Health Sciences in Lahore<\/p>\n\n\n\n<p class=\"bp-blog-byline-date wp-block-paragraph\">Approved on 9 October 2026<\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-takeaways is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\">In short<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li>Iron has been studied the most. Six studies looked at tired people who had an iron deficiency but no anaemia, and in them iron reduced fatigue slightly more than a placebo did.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">1<\/a><\/sup><\/li>\n\n\n<li>In a study of tired people with low vitamin D, 72 per cent felt less tired four weeks after a single dose of vitamin D. In the placebo group, it was 50 per cent.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">2<\/a><\/sup><\/li>\n\n\n<li>A review of 16 studies on vitamin B12 found that only one looked at unexplained tiredness, so nobody knows yet whether extra B12 helps with fatigue.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">3<\/a><\/sup><\/li>\n\n\n<li>If you are tired and have no other symptoms, a blood test rarely finds a cause.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">4<\/a><\/sup> The energy scan measures how much fatigue you are carrying. It is not a diagnosis.<\/li>\n\n<\/ul>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-toc is-layout-flow wp-block-group-is-layout-flow\">\n\n<p class=\"bp-blog-toclabel wp-block-paragraph\">Contents<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n\n<li><a href=\"#welke-vitamine-bij-vermoeidheid-welk-tekort-hoort-erbij\">Which vitamin for fatigue: which deficiency goes with it<\/a><\/li>\n\n\n<li><a href=\"#ijzer-de-meeste-studies\">Iron status: where most of the studies are<\/a><\/li>\n\n\n<li><a href=\"#vitamine-d-een-studie-bij-mensen-met-een-lage-waarde\">Vitamin D: a study in people with a low level<\/a><\/li>\n\n\n<li><a href=\"#vitamine-b12-belangrijk-als-je-een-tekort-hebt\">Vitamin B12: important if you are deficient<\/a><\/li>\n\n\n<li><a href=\"#vermoeidheid-bij-de-ziekte-van-crohn\">Fatigue in Crohn&#8217;s disease<\/a><\/li>\n\n\n<li><a href=\"#wanneer-je-naar-de-huisarts-gaat\">When to see your GP<\/a><\/li>\n\n\n<li><a href=\"#wat-de-energiescan-meet\">What the energy scan measures<\/a><\/li>\n\n\n<li><a href=\"#samengevat\">In summary<\/a><\/li>\n\n\n<li><a href=\"#veelgestelde-vragen\">Frequently asked questions<\/a><\/li>\n\n<\/ol>\n\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"welke-vitamine-bij-vermoeidheid-welk-tekort-hoort-erbij\">Which vitamin for fatigue: which deficiency goes with it<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Thuisarts lists what usually causes tiredness:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li>stress, grief or money worries<\/li>\n\n\n<li>worrying, anxiety or depression<\/li>\n\n\n<li>little exercise, an unhealthy diet, smoking or alcohol<\/li>\n\n\n<li>illnesses such as flu, COVID-19, diabetes, thyroid problems and heart conditions<\/li>\n\n\n<li>unwanted side effects of medicines.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">4<\/a><\/sup><\/li>\n\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Food is only one line on that list.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Two deficiencies are known causes of fatigue. With too little iron, you may tire quickly, look pale, get out of breath easily and have restless legs.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup> A B12 deficiency leads to a form of anaemia that can cause tiredness, dizziness, palpitations and ringing in the ears. This kind of deficiency is uncommon.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">6<\/a><\/sup> Vitamin D has also been tested for fatigue, in people with a low level.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">2<\/a><\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In plain words: a deficiency is one possible cause among many others. If your energy dips mainly after lunch, read <a href=\"https:\/\/bioprofile.com\/en\/afternoon-dip-why-energy-drops-after-lunch\/\">why your energy dips after lunch<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"ijzer-de-meeste-studies\">Iron status: where most of the studies are<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">One study followed 198 menstruating women aged 18 to 53 with unexplained fatigue. All of them had low iron stores, and none had anaemia. For 12 weeks they took 80 mg of iron or a placebo every day. With iron, fatigue fell by 47.7 per cent, and with the placebo by 28.8 per cent. Iron made no measurable difference to quality of life, depression or anxiety.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">7<\/a><\/sup> A review of six similar studies found the same pattern. In tired people with an iron deficiency but no anaemia, iron reduced fatigue slightly more than a placebo did.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">1<\/a><\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">What this means for you: if a blood test shows too little iron, even without anaemia, extra iron can make you slightly less tired. The placebo groups also felt better, so not all of the change came from the iron.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Women in their fertile years can get too little iron more easily, because blood is lost during menstruation. For this group the Voedingscentrum advises 16 mg of iron a day. For men, and for women after the menopause, the advice is 11 mg. True iron deficiency with anaemia is rare in the Netherlands. Iron supplements are not recommended without a medical reason, and only a blood test through your GP can show whether you have a deficiency.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"vitamine-d-een-studie-bij-mensen-met-een-lage-waarde\">Vitamin D: one study in people with a low level<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In a double-blind study, 120 tired but otherwise healthy adults with low vitamin D were given either a single dose of 100,000 units of vitamin D3 or a placebo. Their average age was 29. Four weeks later, 72 per cent of the vitamin D group felt less tired. In the placebo group, it was 50 per cent.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">2<\/a><\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">What this means for you: in people who were tired and had little vitamin D, a dose made a noticeable difference within a month. It was a single study, and it says nothing about people with a normal vitamin D level.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Separately from fatigue, the Voedingscentrum advises an extra 10 micrograms of vitamin D a day for a number of groups. These are children up to 3, women aged 50 to 69, and people aged 4 to 69 who have dark skin or get little sun. Everyone aged 70 and over is advised to take 20 micrograms a day.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">8<\/a><\/sup><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"vitamine-b12-belangrijk-als-je-een-tekort-hebt\">Vitamin B12: important if you have a deficiency<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If you get too little B12, it often takes a few months or even a year before you notice. Three groups are most at risk: people who eat no animal products, people whose bodies absorb B12 poorly, and older adults. Vegans are advised to take a supplement of 2.8 micrograms a day.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">6<\/a><\/sup> Nobody knows whether extra B12 helps against fatigue if you are not deficient. A review of 16 studies found only one that measured unexplained fatigue, and that is too little to draw a conclusion.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">3<\/a><\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In plain words: B12 matters if you are deficient in it. If you are not deficient, there is no evidence that a B12 supplement gives you more energy.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"vermoeidheid-bij-de-ziekte-van-crohn\">Fatigue in Crohn&#8217;s disease<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Of adults with Crohn&#8217;s disease or ulcerative colitis, 47 per cent live with fatigue. That rises to 72 per cent when the disease is active, and in remission it is still 47 per cent. The factors most strongly linked to the fatigue were disturbed sleep, anxiety, depression and anaemia.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">9<\/a><\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">What this means for you: fatigue is common in Crohn&#8217;s disease, even in remission. Sleep, mood and anaemia are the points to discuss with your doctor.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"wanneer-je-naar-de-huisarts-gaat\">When to see your GP<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Contact your GP if your fatigue lasts longer than a month. Also contact your GP if other symptoms come along with it:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li>heavy sweating at night<\/li>\n\n\n<li>less appetite<\/li>\n\n\n<li>changes in your bowel movements<\/li>\n\n\n<li>shortness of breath<\/li>\n\n\n<li>being very thirsty and needing to wee often<\/li>\n\n\n<li>heart palpitations<\/li>\n\n\n<li>feeling very low or very tense.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">4<\/a><\/sup><\/li>\n\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"wat-de-energiescan-meet\">What the energy scan measures<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The energy scan asks five questions about the past two weeks and turns your answers into an energy score. The score shows how much fatigue you are carrying and gives you a baseline to compare against later. A questionnaire cannot measure blood values such as iron, vitamin D or B12, and it cannot find the cause of your fatigue. Finding the cause is a job for a doctor.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"samengevat\">In summary<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Fatigue has many causes, and a deficiency is only one of them.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">4<\/a><\/sup> Iron has been studied the most, and iron helps a little in tired people with an iron deficiency.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">1<\/a><\/sup> In one study, vitamin D made a difference in people with a low level.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">2<\/a><\/sup> For B12, there is too little research on fatigue to say anything.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">3<\/a><\/sup> A blood test through your GP shows whether you have too little iron,\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup> and the energy scan shows how much fatigue you are carrying today.<\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-sec bp-blog-cta is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\">Measure where you start<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Five questions about the past two weeks, about three minutes, and your energy score is in your dashboard. What the energy scan measures and what the scan is based on is on the scan page.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex 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\/scan-fatigue-test\/\">Start the energy scan<\/a><\/div>\n\n<\/div>\n\n\n\n<p class=\"bp-blog-ctamicro wp-block-paragraph\">Free, about 3 minutes. An analysis of your answers, never a diagnosis. <a href=\"https:\/\/bioprofile.com\/en\/free-health-check-tests\/\">All health scans<\/a><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-sec bp-blog-sec--wash is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"veelgestelde-vragen\">Frequently asked questions<\/h2>\n\n\n\n<div class=\"wp-block-group bp-blog-faq-item is-layout-flow wp-block-group-is-layout-flow\">\n\n<h3 class=\"wp-block-heading\">Which vitamin deficiency goes with tiredness: what are you short of if you&#8217;re always tired?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Most of the time there is no deficiency that a blood test can find. If you are tired and have no other symptoms, a blood test rarely shows a cause.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">4<\/a><\/sup> Three deficiencies are linked to tiredness. Vitamin B12 is one of them, but a B12 deficiency is uncommon.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">6<\/a><\/sup> Vitamin D is another, in people with a low level.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">2<\/a><\/sup> The third deficiency is iron, and iron is a mineral.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-faq-item is-layout-flow wp-block-group-is-layout-flow\">\n\n<h3 class=\"wp-block-heading\">Which deficiency causes fatigue?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">With too little iron, you may find that you tire quickly and get out of breath easily.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup> A B12 deficiency leads to a form of anaemia that can cause tiredness and dizziness.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">6<\/a><\/sup> Only a blood test through your GP can show whether you have too little iron.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-faq-item is-layout-flow wp-block-group-is-layout-flow\">\n\n<h3 class=\"wp-block-heading\">Should I take a vitamin for fatigue without a blood test?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Not when it comes to iron. The Voedingscentrum does not advise iron supplements without a medical reason.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">5<\/a><\/sup> Extra vitamin D is recommended for certain groups, such as everyone aged 70 and over,\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">8<\/a><\/sup> and vegans are advised to take B12.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">6<\/a><\/sup><\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-faq-item is-layout-flow wp-block-group-is-layout-flow\">\n\n<h3 class=\"wp-block-heading\">What can you do about fatigue in Crohn&#8217;s disease?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Almost half of adults with Crohn&#8217;s disease or ulcerative colitis live with fatigue, even in remission. The things most strongly linked to it are disturbed sleep, anxiety, depression and anaemia.\u2060<sup class=\"bp-blog-sup\"><a href=\"#bronnen\">9<\/a><\/sup> Those are the points to discuss with your doctor.<\/p>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-faq-item is-layout-flow wp-block-group-is-layout-flow\">\n\n<h3 class=\"wp-block-heading\">Is the energy scan a vitamin test?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The scan measures how much fatigue you have carried over the past two weeks and gives you a baseline. The scan does not measure blood values. It is not a diagnosis.<\/p>\n\n<\/div>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-sec bp-blog-sec--beige bp-blog-sec--tight is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\" id=\"bronnen\">Sources<\/h2>\n\n\n\n<p class=\"bp-blog-srclead wp-block-paragraph\">Every source below was checked on the day this article was published. The numbering follows the text.<\/p>\n\n\n\n<ol class=\"wp-block-list bp-blog-refs\">\n\n<li>Yokoi K, Konomi A. Iron deficiency without anaemia is a potential cause of fatigue: meta-analyses of randomised controlled trials and cross-sectional studies. British Journal of Nutrition, 2017. <a href=\"https:\/\/doi.org\/10.1017\/S0007114517001349\">doi.org\/10.1017\/S0007114517001349<\/a><\/li>\n\n\n<li>Nowak A, Boesch L, Andres E, Battegay E, Hornemann T, Schmid C, Bischoff-Ferrari HA, Suter PM, Krayenbuehl PA. Effect of vitamin D3 on self-perceived fatigue: A double-blind randomized placebo-controlled trial. Medicine (Baltimore), 2016. <a href=\"https:\/\/doi.org\/10.1097\/md.0000000000005353\">doi.org\/10.1097\/md.0000000000005353<\/a><\/li>\n\n\n<li>Markun S, Gravestock I, J\u00e4ger L, Rosemann T, Pichierri G, Burgstaller JM. Effects of Vitamin B12 Supplementation on Cognitive Function, Depressive Symptoms, and Fatigue: A Systematic Review, Meta-Analysis, and Meta-Regression. Nutrients, 2021. <a href=\"https:\/\/doi.org\/10.3390\/nu13030923\">doi.org\/10.3390\/nu13030923<\/a><\/li>\n\n\n<li>Thuisarts.nl (NHG). I am tired. What could it be? <a href=\"https:\/\/www.thuisarts.nl\/moeheid\/ik-ben-moe-wat-kan-zijn\">thuisarts.nl<\/a><\/li>\n\n\n<li>Voedingscentrum. Iron in food. <a href=\"https:\/\/www.voedingscentrum.nl\/encyclopedie\/ijzer.aspx\">voedingscentrum.nl<\/a><\/li>\n\n\n<li>Voedingscentrum. Vitamin B12 (cobalamin). <a href=\"https:\/\/www.voedingscentrum.nl\/encyclopedie\/vitamine-b12.aspx\">voedingscentrum.nl<\/a><\/li>\n\n\n<li>Vaucher P, Druais PL, Waldvogel S, Favrat B. Effect of iron supplementation on fatigue in nonanemic menstruating women with low ferritin: a randomized controlled trial. CMAJ, 2012. <a href=\"https:\/\/doi.org\/10.1503\/cmaj.110950\">doi.org\/10.1503\/cmaj.110950<\/a><\/li>\n\n\n<li>Voedingscentrum. Vitamin D. <a href=\"https:\/\/www.voedingscentrum.nl\/encyclopedie\/vitamine-d.aspx\">voedingscentrum.nl<\/a><\/li>\n\n\n<li>D&#8217;Silva A, Fox DE, Nasser Y, Vallance JK, Quinn RR, Ronksley PE, Raman M. Prevalence and Risk Factors for Fatigue in Adults With Inflammatory Bowel Disease: A Systematic Review With Meta-Analysis. Clinical Gastroenterology and Hepatology, 2022. <a href=\"https:\/\/doi.org\/10.1016\/j.cgh.2021.06.034\">doi.org\/10.1016\/j.cgh.2021.06.034<\/a><\/li>\n\n<\/ol>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-sec bp-blog-sec--tight is-layout-flow wp-block-group-is-layout-flow\">\n\n<h2 class=\"wp-block-heading\">Also read<\/h2>\n\n\n\n<div class=\"wp-block-group bp-blog-related is-layout-flow wp-block-group-is-layout-flow\">\n\n<div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\">\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/bioprofile.com\/en\/afternoon-dip-why-energy-drops-after-lunch\/\">Afternoon slump: why your energy dips after lunch, how long the dip lasts and what helps<\/a><\/p>\n\n<\/div>\n\n<\/div>\n\n<\/div>\n\n\n\n<div class=\"wp-block-group bp-blog-sec bp-blog-sec--foot is-layout-flow wp-block-group-is-layout-flow\">\n\n<p class=\"bp-blog-legal wp-block-paragraph\">BioProfile analyses your health status to guide you and your coach. It does not make a diagnosis, only a doctor can do that. Built on validated health questionnaires; the combined BioProfile score is not itself a validated clinical instrument yet. Your answers stay private (GDPR).<\/p>\n\n<\/div>\n\n<\/article>\n","protected":false},"excerpt":{"rendered":"<p>Which vitamin for fatigue? What studies with iron, vitamin D and B12 found, what a blood test shows and when to see your GP.<\/p>\n","protected":false},"author":18,"featured_media":7698,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_yoast_wpseo_meta-robots-noindex":"2","_yoast_wpseo_opengraph-image":"","_yoast_wpseo_opengraph-image-id":"","_yoast_wpseo_twitter-image":"","_yoast_wpseo_twitter-image-id":"","inline_featured_image":false,"footnotes":""},"categories":[75],"tags":[],"class_list":["post-8006","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-energy-en"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Which vitamin for fatigue? Iron, vitamin D and B12 | BioProfile<\/title>\n<meta name=\"description\" content=\"Which vitamin for fatigue? 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