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Vitamin B12

Vitamin Unit: pg/mL

Essential for nerve function and DNA synthesis

Also known as: Cobalamin,B12,Cyanocobalamin,Vitamin B12; Cyanocobalamin

Reference Ranges

Clinical Reference 200.0 – 900.0 pg/mL

Optimal Range 400.0 – 700.0 pg/mL

Critical Range < 150.0 pg/mL

Functional deficiency possible at 200-400

Related Conditions

Anemia Low

Depression Low

Neuropathy Low

Food & Lifestyle Recommendations

🍎 Food Increase intake of B12-rich foods: meat, fish, eggs, dairy; fortified nutritional yeast for vegetarians B12 is only found naturally in animal products

Evidence-Backed Supplements

When Low

Vitamin B12 Tier A May Increase

Direct supplementation; sublingual or injection if absorption impaired

Methylcobalamin or cyanocobalamin 1000–5000 mcg/day (sublingual preferred) Morning

PMID 40147066 PMID 30431328 PMID 29543316
Folate Tier A Supports Normalization

Works synergistically with B12 in methylation

Methylfolate (5-MTHF) 400–1000 mcg/day Morning

PMID 28816346 PMID 25803792 PMID 32770489

Questions to Ask Your Doctor

Could my B12 deficiency be due to absorption issues rather than dietary intake? Ask about intrinsic factor antibodies and gastritis
Should I try sublingual B12 or do I need injections? Sublingual works if not pernicious anemia; injections bypass gut

Upload your blood test to see how your Vitamin B12 compares to reference and optimal ranges.

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