Vitamin B12
Learn about Vitamin B12 levels for nerve function and red blood cell health assessment. Monitor B-vitamin status for wellness tracking.
What is Vitamin B12?
Vitamin B12 (cobalamin) is an essential nutrient required for red blood cell formation, neurological function, and DNA synthesis. Your body cannot produce B12, so it must be obtained from animal products or supplements, and deficiency can develop over years.
Why is it Tested?
Doctors test B12 to investigate anemia (especially megaloblastic), neurological symptoms like numbness or cognitive changes, and fatigue. It’s also checked in vegans, older adults, and people with absorption disorders who are at higher risk for deficiency.
Normal Ranges
Reference ranges for vitamin B12:
- Deficient: <200 pg/mL
- Normal: 200–900 pg/mL
Some experts suggest optimal levels should be >400 pg/mL, as neurological symptoms can occur even with “normal” levels.
Reference ranges vary by authority. Track yours across multiple standards with automatic unit conversions in LabsVault.
What do Abnormal Results Mean?
Abnormal results are not a diagnosis. Always discuss your results with a qualified healthcare provider before making any medical decisions.
Low Vitamin B12
Deficiency may cause:
- Megaloblastic anemia
- Neurological symptoms (numbness, memory issues)
- Fatigue and weakness
- Glossitis (inflamed tongue)
- Mood changes or depression
High Vitamin B12
Excessive levels may indicate:
- Recent B12 supplementation
- Liver disease
- Kidney disease
- Blood disorders like leukemia
How to Track Over Time
B12 levels decline slowly as body stores are depleted, typically taking months to years. Once deficiency develops, monitoring helps ensure adequate repletion with supplements or injections. Regular tracking is especially important for those with absorption issues or dietary restrictions.
Track your Vitamin B12 results over time
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