Vitamin B1 Deficiency

General text about the lack of vitamins can be found here.


Vitamin B1 is name given to a substance known as thiamine. It is a water-soluble vitamin that that can not be produced by our organism and therefore it must be taken in diet. Thiamine is an important part of enzymatic reactions that are necessary for metabolism of essential nutrients including production of certain neurotransmitters (chemical substances transmitting neuroelectric signals among the neurons).


Very rich content of thiamine can be found in yeast, cereals, rice husks, eggs, potatoes, liver and meat, especially in pork.


Thiamine deficiency may be linked to an inadequately low intake in the diet. In developed countries, it is usually reported in chronic alcoholics with liver damage and severely ill patients. In addition to decreased dietary intake, thiamine deficiency occurs in patients with impaired nutrient absorption in the digestive tract.


The lack of vitamin B1 affects mainly our central nervous system and cardiovascular system. Fully developed disease is called beriberi (beri-beri) and it has two forms – dry and wet beriberi. In dry beriberi, neural damage is dominant manifesting as polyneuropathy with tingling sensations in the limbs, disturbed reflexes and disorders of sensitivity or even cases of muscle paralysis. Wet beriberi affects mainly the cardiovascular system causing signs of heart failure (shortness of breath, leg swelling, etc.). It is rare to see a patient with fully developed beriberi in civilized countries. It is much more probable to diagnose a patient with milder forms of B1 deficiency manifesting with fatigue, loss of appetite, palpitations, headache, and other unspecific troubles.


Damage to the optic nerve in more serious thiamine deficiency can cause blurred vision, impaired color vision and visual field failures. The brain is typically affected in alcoholics, where thiamine deficiency is an important causative factor for Korsakoff’s syndrome, which leads to memory disorders, dementia and confabulation (making up of the missing memories).


The diagnosis is probable in some of the above-mentioned symptoms in a patient who has some of the risk factors of thiamine deficiency (see Causes). In chronic alcoholics, it is advisable to regard thiamine deficiency as a sure thing.


Thiamine can be administered in dietary supplements as part of the B-complex. As it is a water-soluble vitamin that is excreted by urine, it is not easy to get overdosed by thiamine.


Jiri Stefanek, MD  Author of texts: Jiri Stefanek, MD
 Sources: basic text sources