Vitamin B12 is stored in the kidneys, liver and other body
tissues and as a result, the signs and symptoms of vitamin
B12 deficiency may not show themselves until 5-6 years of
poor dietary intake. The classic symptom of vitamin B12
deficiency is anemia; however it appears that a deficiency
will affect the brain and nervous system first. This can lead
to impaired nerve function such as a feeling of numbness,
a pins and needles sensation as well as mental function.