Check your vitamin D levels from the comfort of home. No fasting required, no GP referral needed. Professional venous blood collection by a verified mobile phlebotomist.
Find a Phlebotomist →The standard vitamin D blood test measures 25-hydroxyvitamin D, the best indicator of your overall vitamin D status.
| Level | Range (nmol/L) | Interpretation |
|---|---|---|
| Deficient | Below 25 nmol/L | Treatment with high-dose supplementation usually needed |
| Insufficient | 25 - 50 nmol/L | Supplementation recommended |
| Adequate | 50 - 75 nmol/L | Generally sufficient for most people |
| Optimal | 75 - 150 nmol/L | Recommended range for optimal health |
Vitamin D deficiency is a common cause of persistent tiredness and seasonal low mood, especially in winter months.
Low vitamin D can cause bone pain, muscle weakness and increase the risk of osteoporosis, particularly in older adults.
Higher melanin levels reduce the skin's ability to produce vitamin D from sunlight, increasing the risk of deficiency.
Office workers, housebound individuals and care home residents are at higher risk of vitamin D deficiency.
Enter your postcode, pick a time, and select the vitamin D test. No GP referral required.
A DBS-checked mobile phlebotomist arrives at your home and collects a venous blood sample in under 10 minutes.
Your sample is dispatched to an accredited laboratory the same day. Results typically within one to three working days.
No fasting is required for a vitamin D test.
If testing to check supplementation levels, continue taking your supplements as normal.
Stay well hydrated to make the blood draw easier.
Wear loose-fitting sleeves for easy arm access.
Note down any supplements you are currently taking for your phlebotomist.
Vitamin D is essential for bone health, immune function, muscle strength and mood regulation. It helps your body absorb calcium and phosphate. Deficiency is extremely common in the UK due to limited sunlight, particularly between October and March, and can cause fatigue, bone pain, muscle weakness and low mood.
No. Vitamin D testing does not require fasting. You can eat and drink normally before your appointment.
Very common. Public Health England estimates that around 1 in 5 people in the UK has low vitamin D levels. The risk is higher during autumn and winter, for people with darker skin, those who cover most of their skin, and those who spend little time outdoors.
A level above 50 nmol/L (20 ng/mL) is generally considered adequate. Between 25-50 nmol/L is insufficient, and below 25 nmol/L is deficient. Some doctors recommend optimal levels of 75-100 nmol/L, particularly for people with bone conditions or immune system concerns.
It depends on the purpose of your test. If you want to check whether your current supplementation is adequate, continue taking them. If you want to see your baseline level without supplementation, discuss with your doctor whether to pause. Do not stop any prescribed medication without medical advice.
Find a DBS-checked phlebotomist near you. Most bookings confirmed in under two minutes.
Find a Phlebotomist →Related reading: Vitamin D Deficiency in the UK: What You Need to Know