Educational information only. At Precursor, blood testing is requested and reviewed by a clinician and considered alongside your history and other markers, not as a stand-alone diagnosis. Testing is performed in NATA-accredited laboratories to ISO 15189 standards.

What is vitamin D?

Vitamin D is a hormone-like nutrient your body mainly makes when skin is exposed to sunlight, with a smaller amount from food. It is essential for absorbing calcium and maintaining strong bones, and it also plays a role in muscle function and immunity. The blood test measures the storage form, 25-hydroxyvitamin D.

Why it matters

Vitamin D is one of the more common deficiencies, even in sunny Australia, particularly in winter, for shift workers, and for people who cover up or spend most of the day indoors. Because it underpins bone health and more, it is a worthwhile and easily correctable marker to know.

What your results can mean

Lower than optimal

A low vitamin D can affect calcium absorption and bone health over time, and is often linked to limited sun exposure. It is one of the more straightforward deficiencies to address with clinical guidance.

Within the healthy range

A vitamin D in the sufficient range supports bone, muscle and immune function. Very high levels, usually from over-supplementing, are worth avoiding.

Reference ranges in Australia

Vitamin D is reported in nanomoles per litre (nmol/L). As a general guide, a level of 50 nmol/L or above is often considered sufficient, with somewhat higher levels sometimes targeted at the end of winter. Read your result against your own report and with a clinician.

Test your vitamin D with Precursor

Vitamin D is best read alongside calcium and your wider nutrient markers. At Precursor it is measured as part of Full Advanced Bloods, a single clinician-reviewed blood draw covering your vitamins, bone, heart, metabolic, hormonal and other markers together, giving you and your clinician a broad baseline to understand and track.