25-Hydroxy Vitamin D (25-OH D)

Best marker of vitamin D status. Deficiency is one of the most common findings in modern lab panels.

Units

ng/mL

Reference (Male)

30 – 100 ng/mL

Reference (Female)

30 – 100 ng/mL

Aliases

Calcidiol

What it measures

Best marker of vitamin D status. Deficiency is one of the most common findings in modern lab panels.

What a high value can mean

Vitamin D supplementation, sarcoidosis, rare toxicity (> 100 ng/mL).

What a low value can mean

Sun avoidance, dark skin, obesity, malabsorption, kidney/liver disease, aging.

Conditions it helps assess

Bone health
Immune function
Mood

Reading these numbers in context

Reference ranges describe the central 95 % of a healthy reference population — 5 % of perfectly healthy people fall outside any given range by definition. A single mildly abnormal value is rarely meaningful on its own. blood-test.life always interprets values together with related biomarkers before flagging.

Related biomarkers in Vitamins & Minerals

Vitamin B12 B12 Water-soluble vitamin needed for nerve function, DNA, and red cell production. Folate B9 B-vitamin essential for DNA synthesis. Critical in pregnancy to prevent neural tube defects.