Vitamin D
Your bones rely on vitamin D to absorb calcium and maintain strength, but this essential nutrient also supports your energy levels and immune function. With limited sunlight for much of the year, deficiency is incredibly common. This quick blood test checks whether your levels are where they need to be.
Choose how you'd like your sample taken
Pick the option that suits you. The test is the same — only the way we collect your sample changes.
- GP-written interpretation by Dr James Coleman
- UKAS-accredited UK laboratory
- Results in 2–3 working days
No subscription. No hidden fees. Same-day dispatch. Ordering more than one test? Place each order separately — each one ships as its own kit with its own doctor's report.

Dr James Coleman
“Every Brooksby report is written personally. You get a plain-English interpretation and a clear next step — not just numbers on a page.”
Simple from start to finish
Order your test
Choose online in minutes. Your kit ships the same working day.
Collect your sample
Finger-prick or Venous collection
Post it back
Drop your pre-paid, tracked envelope in any postbox. We take it from there.
Your GP-written report
Reviewed by a practising GP. Delivered to your secure portal within 2–3 working days.
Book your doctor review
Receive a link to book a private call with your doctor to discuss your results and the next steps that make sense for you.
Every result comes with a written report
What you actually get in this test
1 marker analysed by a UKAS-accredited UK laboratory.
A GP-led service, not a lab with a website
GP-written report included
Every report is written by Dr Coleman, a practising GP. No extra charge.
A named doctor, not a team
Your report is signed by Dr Coleman personally. Not an anonymous review pool.
UKAS-accredited UK lab
Same accreditation standard used by NHS hospitals. Consistent, reliable analysis.
One-off, no subscription
You order the test, you get the report, you own the data. No ongoing fees.
Common questions
Everything you need to know before ordering your Vitamin D.
What does a vitamin D blood test measure?
This test measures the level of 25-hydroxyvitamin D in your blood, which is the main circulating form of vitamin D. It reflects your overall vitamin D status from both sunlight exposure and dietary intake, and is the standard marker used by doctors to assess bone health and immune function.
Who should consider a vitamin D test?
Vitamin D testing is particularly useful for:
People who spend limited time outdoors or live in the UK
Those with darker skin tones
Anyone experiencing fatigue, bone pain, or muscle weakness
People supplementing vitamin D who want to check levels
Those with conditions affecting absorption (e.g. coeliac, Crohn's)
What is a normal vitamin D level in the UK?
In the UK, vitamin D levels are typically reported in nmol/L:
Below 25 nmol/L — deficient
25–50 nmol/L — insufficient
50–75 nmol/L — adequate
75–150 nmol/L — optimal
Your GP report will explain where your result falls and recommend next steps.
Do I need to fast for a vitamin D test?
No fasting is required. You can eat and drink normally before this test. Stay well hydrated for an easier blood draw.
How will I receive my vitamin D results?
Secure online results with a GP-written explanation from Brooksby Medical in 2–3 working days.
More about Brooksby
How accurate are the results?
Who writes the reports?
How long do results take?
Do I need a GP referral?
Can I share my results with my NHS GP?
What happens if something is abnormal?
What is the difference between venous and fingerprick?
Is my data kept private?
Ready to order?
A simple sample, a UKAS-accredited lab, a GP-written report with clear next steps.
Order my Vitamin D →
