ABOUT THIS TEST
What is Vitamin D and why is it important?
Vitamin D is actually a hormone which helps regulate the amount of key minerals such as calcium and phosphate in the body. It is crucial for maintaining healthy bones, teeth and muscles.
We maintain health Vitamin D levels n three ways:
- We make it in the the skin from sunlight exposure
- We can find sources of vitamin D from our diet
- We can take vitamin D supplementation
In the UK, from around the end of March to the end of September, most people can obtain adequate amounts of vitamin D from direct sunlight on the skin when outdoors and a healthy balanced diet.
Between October and March, the sunlight is generally not strong enough to make adequate vitamin D, so it must be obtained from the diet or supplementation.
Please note: these tests are available for people aged over 18 only. In a small number of cases, it may not always be possible to provide a result, please see our terms and conditions for details.
WHO IS THIS TEST FOR
This test will allow you to know exactly what your vitamin D levels are now. We will let you know if you have enough, or if you require supplementation
There are two types of Vitamin D called D2 and D3. Vitamin D2 is made in plants and Vitamin D3 is produced in the skin with sunlight exposure. Both forms can be found in the diet and in supplements. Our Vitamin D test measures both D2 and D3. The result produced is the total of both D2 and D3 together.
People who may be at risk of Vitamin D deficiency include:
- The elderly, especially if frail/house-bound
- People with dark skin (African, African-Caribbean and South Asian ethnicities)
- People who are very overweight (obese) or have had gastric bypass surgeries
- Pregnant women and women who are breastfeeding
- Anyone who may spend very little time outdoors
- People with certain conditions, such as liver disease, kidney disease or cystic fibrosis (CF)
- People with malabsorption conditions e.g. Coeliac’s disease or Crohn's disease
- People who have already been diagnosed with bone disease such as osteoporosis, osteomalacia, or Paget’s disease
What does the result mean?
Interpretation of Vitamin D results:
- Less than 10 nmol/L: Deficient, suggests Vitamin D replacement. You should contact a health care professional
- 10 - 35 nmol/L: Insufficient, suggests Vitamin D supplementation would be appropriate.
- 36 - 60 nmol/L: Adequate. For optimal bone health, concentrations at the upper end of the reference range may be preferable and advice regarding diet and safe sun exposure may be appropriate.
- Greater than 60 nmol/L: Optimal.