Vitamin D Evaluator
Metabolic Relevance
Vitamin D influences insulin sensitivity, immune function, and metabolic health. Levels below 30 ng/mL are associated with increased insulin resistance and metabolic syndrome risk. Optimal levels (50-80 ng/mL) support glucose metabolism and reduce inflammation.
Recommended testing frequency:
Every 6-12 months, or quarterly when supplementing to reach optimal levels
Did you know?
Vitamin D is actually a hormone, not a vitamin. Our skin produces it when exposed to sunlight, but most people don't get enough sun exposure, especially in winter months.
The optimal range of 50-80 ng/mL (125-200 nmol/L) is higher than the laboratory "normal" range. Many researchers consider 30 ng/mL (the typical lab cutoff) to be the minimum, not the target.
Want to understand your result better?
Learn about interpretation, what affects your score, and evidence-based strategies to improve it.
Read the full guideEvidence-Based
This calculator is based on peer-reviewed research validated across thousands of clinical studies.
View scientific references(11)Medical Disclaimer
Why Optimal Thresholds Differ?
Standard Medical
⚠️ Focused on preventing deficiency diseases
Research Consensus
✓ Associated with lowest all-cause mortality
Metabolic Optimization
🔬 Optimal for insulin sensitivity and immunity