How to detect vitamin B12 deficiency?

    A blood test may not give an accurate result, a serum (blood) test measures the total amount of B12, which includes inactive as well as active B12. So B12 may appear normal or high, even though it is in an unusable form. A functional approach to B12 assessment will look at:

Symptoms – numbness and tingling, fatigue, weakness, memory problems, anemia.

Gut health – gastritis or any structural damage

Autoimmune risk – (family history) pernicious anemia

Medications – proton pump inhibitors (PPIs), metformin and histamine blockers – reduce stomach acid and the ability to absorb B12

Diet – low intake particularly of meat, dairy and eggs. ⠀

 

FUNCTIONAL TESTS

Metabolomics:⠀Methylmalonic acid is a functional test to evaluate vitamin B12 in its active form.

Genetics: the polymorphisms related to vitamin B12 are:

FUT2 - may impact its absorption/⠀ bifidobacteria

TCN - transport and delivery into cells/ hydroxocobalamin

MTR - activates/methylates B12 and MTRR - recycles/reactivates B12/⠀ methylcobalamin

MUT - converts methylmalonyl co-enzyme A into succinyl-co-enzyme/adenosylcobalamin