Health topic · Nutrition
Vitamin D deficiency
Vitamin D helps keep bones and muscles healthy. Learn who is more likely to have low levels, how it is tested and what general guidance says.
Written by LON6EVITY Editorial Team · Last updated
Overview
The NHS explains that vitamin D helps regulate calcium and phosphate, which are needed to keep bones, teeth and muscles healthy. Most is made in the skin from sunlight.
Who is at higher risk
People who get little sun, have darker skin, cover most of their skin outdoors or spend long periods indoors are more likely to have low levels, according to the NHS.
Testing
Vitamin D status is measured with a 25-hydroxyvitamin D blood test. Levels vary by season, so timing matters when comparing results.
General guidance
The NHS suggests many adults consider a daily 10 microgram supplement in autumn and winter, and warns against taking too much. Individual needs should be discussed with a clinician.
Factors that can affect the result
- Limited sun exposure
- Darker skin
- Season
- Diet
Questions people commonly ask
- Can you take too much vitamin D?
- Yes. Very high doses over time can cause harm, so follow recommended amounts.
Related biomarkers
Understand your biomarkers in context
What does this mean for your own health data? Log your results, follow trends over time and bring an organised summary to your next doctor's appointment.
Sources
- Vitamin D. NHS.