Functions:
- helps form new cells
- helps support a healthy nervous system
Sources:
- meat
- poultry
- fish
- eggs
- milk
- cheese
Deficiency (Not enough):
- anemia
- fatigue
Toxicity (Too much):
- no toxic side effects
Daily Allowances:
- 300mcg
Vitamin B12
By Mark Cichocki, R.N., About.com
Updated: December 21, 2004
About.com Health's Disease and Condition content is reviewed by the Medical Review Board
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