vitamin B1 deficiency
Last reviewed 01/2018
Thiamine, in its active form as thiamine pyrophosphate, acts as a co-factor for three enzymes involved in the metabolism of carbohydrates:
- pyruvate dehydrogenase, in glycolysis
- alpha-ketoglutarate dehydrogenase, in the citric acid cycle
- transketolase, in the pentose phosphate pathway
Consequently, deficiency tends to affect organs dependent on carboyhdrates e.g. the CNS, liver, heart and skeletal muscle.
Body stores of thiamine are small, so a deficiency state appears rapidly if dietary intake is inadequate.
Thiamine is ubiquitous, hence deficiency is only encountered in the following circumstances:
- in countries where the only food is polished rice; this is called beri-beri
- amongst alcoholics who eat almost nothing
- in a starved patient, for example with carcinoma of the stomach