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Vitamin D and B12
testing in London
Two of the commonest deficiencies in the UK, and two of the easiest to put right once you know.
Two deficiencies that look identical from the outside
Tired, foggy, low, aching. Vitamin D deficiency and B12 deficiency both produce that picture, and so does low iron and an underactive thyroid. From the outside they are hard to tell apart, which is why guessing and buying supplements is such a common and such an unsatisfying approach.
Vitamin D deficiency is genuinely widespread here. Between October and March there is not enough UV in British sunlight for your skin to make it at all, and darker skin, working indoors, and covering up all reduce it further. It is not an exotic diagnosis.
B12 is a different situation. Deficiency is commonest in people on vegan or largely plant-based diets, in people taking metformin or long-term acid-reducing medication, in older adults, and in anyone with a gut condition affecting absorption. Left long enough it can cause nerve symptoms, which is the reason not to sit on it.
What happens
Knowing which one, and how low
The £89 consultation covers the appointment. Vitamin D is £62 and B12 with folate is £112, charged in addition.
The appointment
At our Nine Elms clinic.
After the result
A plan, not just a number.
Who this is for
Reasons people get checked
Winter exhaustion
Flat and drained from November onwards, every year, in a way that summer does not produce.
Vegan or plant-based diet
B12 comes almost entirely from animal sources. Supplementation is usually needed rather than optional.
Aching muscles and bones
A recognised feature of vitamin D deficiency, and often put down to age or exercise.
Pins and needles or numbness
A B12 symptom that should not be ignored, because prolonged deficiency can cause lasting nerve damage.
Long-term medication
Metformin and long-term acid-reducing drugs both affect B12 absorption over time.
Darker skin, or little sun exposure
Both substantially reduce how much vitamin D your skin can make. Widely under-recognised.
If B12 is low, the useful question is why. In some people it is diet and easily corrected. In others it reflects an absorption problem that needs identifying, so the GP will look at that rather than simply starting a supplement.
Questions
Things people ask us
Can I just take a supplement and skip the test?
You can, and for vitamin D over winter that is reasonable for many people. The reason to test is that it tells you how low you actually are, which determines the dose and how long you need it for. With B12 it matters more, because a deficiency can point to an absorption problem that supplements alone will not solve.
Do I need to fast?
No. Neither test requires fasting. If you already take a B12 supplement or have had a recent injection, tell us, because it affects how the result should be read and sometimes whether it is worth testing at all just now.
How long does treatment take?
Vitamin D usually corrects over a couple of months on the right dose. B12 depends on the cause: dietary deficiency responds well to tablets, while an absorption problem needs injections, which we give here. The GP will explain which applies to you and arrange it at the appointment.
Should my children be tested?
We see children from newborn, and vitamin D supplementation is routinely recommended for young children in the UK. Whether testing is warranted depends on the situation. Book a consultation and we will advise rather than testing them by default.
Related
Often tested at the same time
Find out which one it is
Both are common, both are correctable, and guessing wastes months.