Vitamin D (25-OH)

Vitamin Unit: ng/mL

Critical for bone health, immune function, and mood

Also known as: 25-Hydroxy Vitamin D,25(OH)D,Vitamin D 25 Hydroxy,25 Hydroxy Vitamin D

Reference Ranges

Clinical Reference 30.0 – 100.0 ng/mL

Optimal Range 40.0 – 70.0 ng/mL

Critical Range < 10.0 / > 150.0 ng/mL

Deficiency <20; insufficiency 20-29; sufficient >30

Osteoporosis Low

Depression Low

Immune Deficiency Low

🍎 Food Include fatty fish (salmon, sardines, mackerel), egg yolks, and fortified dairy or plant milk Fatty fish provides 200-600 IU per serving

🍎 Food Some mushrooms exposed to UV light contain vitamin D2 (look for UV-treated labels) UV-exposed mushrooms can provide 400-800 IU per serving

💡 Other Get 10-20 minutes of midday sun exposure (arms/face) when UV index is 3+ UVB triggers vitamin D synthesis in skin; time varies by skin tone

Vitamin D Tier A May Increase

Strong evidence; direct supplementation raises 25(OH)D levels

Vitamin D3 (cholecalciferol) 2000–5000 IU/day Morning

PMID 19370554 PMID 24414552 PMID 24729336
Magnesium Tier A May Increase

Required cofactor for vitamin D activation

Magnesium glycinate or citrate 200–400 mg elemental Mg/day Evening, before bed

PMID 33419615 PMID 23440790 PMID 32956536
Vitamin K Tier A Supports Normalization

Works synergistically with vitamin D for calcium metabolism

PMID 25092359 PMID 28968483 PMID 27027384

What dose and form of vitamin D supplementation would be appropriate for my level? D3 is preferred; dosing depends on severity
Should I also check my calcium and PTH levels given my low vitamin D? Low D can cause secondary hyperparathyroidism

Upload your blood test to see how your Vitamin D (25-OH) compares to reference and optimal ranges.