Vitamin D - 25(OH)D in Serum

Major circulating vitamin D storage marker used to assess vitamin D status. Influenced by UVB exposure, intake, absorption, adiposity, liver hydroxylation, and season.
Also known as:
Total 25-Hydroxyvitamin D (D2 + D3)
S-25-OH-D
Vitamin D
Vitamin D total
25-hydroxy-vitamin D
.

Vitamin D - 25(OH)D ranges

Interpret your result
"Normal" lab range for Vitamin D - 25(OH)D is between 10.2 and 49.4 ng/mL:
10.2
49.4
According to Peter Attia, Vitamin D - 25(OH)D should be between 30 and 80 ng/mL:
30
80
According to OptimalDX, Vitamin D - 25(OH)D should be between 50 and 90 ng/mL:
50
90
Optimal range
Optimal range for Vitamin D - 25(OH)D appears to be between 30 and 80 ng/mL:
0
20
30
80
100
150
Why this optimal range?
Preliminary range is based on functional health organizations including but not limited to those listed above.

What a low value may mean:

Common reasons for low Vitamin D - 25(OH)D:

  • Low 25(OH)D usually reflects low UVB exposure or intake: limited sun exposure, dark skin pigmentation, high-SPF sunscreen use, winter latitude, low intake of fatty fish or fortified foods, or strict vegan diets.

    Other common causes are malabsorption or altered distribution/metabolism: obesity, bariatric surgery, celiac disease, Crohn's disease, cholestasis or pancreatic insufficiency, liver or kidney disease, magnesium insufficiency, and medications such as anticonvulsants, glucocorticoids, rifampin, antiretrovirals, and some antifungals.

    ,,

What a high value may mean:

Common reasons for high Vitamin D - 25(OH)D:

  • High 25(OH)D is most often supplement-driven via excessive vitamin D dose. Sun exposure alone does not usually cause vitamin D toxicity.

    Less common: increased active vitamin D production in granulomatous disease or lymphoma, and rare cholecalciferol-containing rodenticide exposure. The main practical concern is hypercalcemia, especially when levels exceed about 100-150 ng/mL.

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Zsolt Szabo
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