Vitamin deficiency

Vitamin deficiency

Test name

Vitamin B1
(Thiamine)

RBC transketolase

Vitamin B2
(Riboflavin)

Glutathion reductase

Vitamin B6

RBC transaminase

Vitamin B6
(Pyridoxine)

Tryptophan load test
(measure xanthuric acid)

Vitamin B9

Histidine load test
(measure FIGLU excretion)

Vitamin B12

Methylmalonic acid
(MMA)

Vitamin B12

Schilling test
(Measures the absorption of radiolabeled B12)