vitamin
Vitamin B12
Supports neurologic function, methylation, and red blood cell formation.
What It Does
B12 is essential for myelin and neurologic function.
It works with folate in methylation and red blood cell production.
Who Needs It Most
| Demographic | Target Intake | Upper Limit |
|---|---|---|
| all, age:51-120 | 2.4 mcg | No established UL |
| all, vegan | 2.4 mcg (often 250-1000 mcg supplemented) | No established UL |
| all, vegetarian | 2.4 mcg | No established UL |
| female, pregnant, breastfeeding | 2.6 mcg | No established UL |
| all, digestive | 2.4 mcg | No established UL |
| female, postmenopause, perimenopause | 2.4 mcg (sublingual recommended) | No established UL |
Signs of Deficiency
- Fatigue
- Numbness or tingling
- Memory or mood changes
Best Food Sources
Shellfish
High
Meat and dairy
Moderate to high
Fortified plant milks
Variable
Supplement Guide
Best forms: Methylcobalamin, Cyanocobalamin
What to look for: Sublingual or oral forms with adequate dose
What to avoid: Ignoring deficiency signs in older adults or vegans
Timing: Morning, with or without food.
Who Should Avoid It
No major common contraindications in our database for this nutrient. Always check medication interactions.
The Research
PubMed citations are temporarily unavailable.
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