Biomarker table
Inflammation
hs-CRP
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Iron status
Ferritin
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Thyroid hormones
TSH
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Free thyroxine
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Vitamins
Vitamin B12 - active
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Vitamin D
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Despite its name, vitamin D is actually a hormone that’s produced by your skin when it’s exposed to sunshine. Before your body can use vitamin D produced by sun exposure (known as vitamin D3), it must be converted into another form called 25 hydroxycholecalciferol (25 OH). Vitamin D (25 OH) is the major circulating form of vitamin D, and so your vitamin D (25 OH) level is considered the most accurate indicator of vitamin D supply to your body.
Vitamin D is essential for healthy bones and teeth, as it helps your body absorb calcium. It also plays a role in muscle health, immune function, and mental health.
Low vitamin D symptoms include muscle weakness, mood swings, and fatigue. Many people in the UK have low vitamin D levels, and people with dark skin and people who don’t spend much time outdoors are particularly at risk.
Small amounts of vitamin D can be obtained from food, especially oily fish, eggs, and vitamin-D fortified foods. But if you have a vitamin D deficiency, you’re unlikely to be able to improve your levels by food alone.
How to prepare for your test
Prepare for your Driver's Tiredness Blood Test by following these instructions. Take your sample between 6am and 10am. Take this test when any symptoms of short-term illness have settled. Take your sample at least 24 hours after any vitamin or mineral supplements. Do not take biotin supplements for two days before this test, discuss this with your doctor if it is prescribed. Do not take vitamin B12 for two weeks prior to this test. If your B12 is prescribed ask your doctor whether to stop.
How it works
Your personalised, actionable health results are only a few clicks away. Order your test, take and post your sample, then view your results online with our doctors' comments.
Track, improve, and monitor your health over time
MyMedichecks is your personal online dashboard where you can view your results, access clear and simple explanations about individual health markers, monitor changes in your health, and securely store information about your medical history, lifestyle, and vital statistics.