What happens if you don't get enough vitamin B1?

A thiamine deficiency can lead to numerous problems including neurodegeneration, wasting, and death.

A lack of thiamine can be caused by malnutrition, alcoholism, a diet high in foods such as raw freshwater fish or raw shellfish which break down B1 in the body and/or foods high in anti-thiamine factors (tea, coffee, betel nuts).

Vitamin B1 and alcoholism

Well-known syndromes caused by thiamine deficiency include Wernicke-Korsakoff syndrome and beriberi, diseases also common with chronic alcoholism.

Wernicke-Korsakoff Syndrome

The syndrome is a combined manifestation of two disorders, Korsakoff's Psychosis and Wernicke's encephalopathy, named for Drs. Sergei Korsakoff and Carl Wernicke.

Korsakoff's psychosis is characterized by

confusion
anterograde and retrograde amnesia
confabulation (fabrication of experiences and events to cover gaps in memory)

Wernicke's encephalopathy is characterized by

nystagmus (involuntary movements of the eyes)
ophthalmoplegia (weakness of the eye muscles)
anisocoria (difference in size of pupils in the eyes)
ataxia (co-ordination problems)
sluggish pupillary reflexes
coma and death if untreated

Causes

Wernicke-Korsakoff syndrome results from severe acute deficiency of thiamine (Vitamin B1) on top of an already chronic deficiency.

As stated above, Wernicke-Korsakoff in the United States is usually found in malnourished chronic alcoholics, though it is also found in patients who undergo prolonged intravenous (IV) therapy, gastric stapling or intensive care unit (ICU) stays. In some regions, the syndrome can be brought about by the chronic intake of polished rice, which is thiamine deficient.

Wernicke-Korsakoff syndrome in alcoholics especially is associated with atrophy of part sof the brain.

Diagnosis

Diagnosis of Wernicke-Korsakoff syndrome is by clinical impression and can sometimes be confirmed with formal Neuropsychological assessment. Wernicke's encephalopathy typically presents with ataxia and nystagmus, and Korsakoff's psychosis with anterograde and retrograde amnesia and confabulation upon relevant lines of questioning.

Treatment

Treatment consists of reversing the thiamine deficiency by giving supplemental thiamine, usually by starting with an initial intravenous or intramuscular dose followed by supplemental oral doses. It is important to start the thiamine treatment before giving any glucose as the encephalopathy will be worsened by the glucose. By the time amnesia and psychosis have occurred, complete recovery is unlikely.

Beriberi

Beriberi is caused by a lack of thiamine. It is common in people whose diet consists mainly of polished white rice (which contains little or no thiamine because the husk, which contains most of the thiamine, has been removed) and in chronic alcoholics with an inadequate diet; it is also a known (though rare) potential side effect of gastric bypass surgery. If a baby consumes the milk of a mother who suffers from thiamine deficiency, the child may develop beriberi.

The disease has been seen traditionally in people in Asian countries (especially in the 19th century and before), due to those countries' reliance on white rice as a staple food.

Symptoms and effects

Its symptoms include weight loss, emotional disturbances, impaired sensory perception (Wernicke's encephalopathy), weakness and pain in the limbs, and periods of irregular heart rate. Edema (swelling of bodily tissues) is common. In advanced cases, the disease may cause heart failure and death.

There are two forms of the disease: wet beriberi and dry beriberi.

Wet beriberi affects the heart; it is sometimes fatal, as it causes a combination of heart failure and weakening of the capillary walls, which causes the peripheral tissues to become waterlogged.
Dry beriberi causes wasting and partial paralysis resulting from damaged peripheral nerves. It is also referred to as endemic neuritis.

Treatment

Treatment is with thiamine hydrochloride, either in tablet form or injection. A rapid and dramatic recovery within hours can be made when this is administered to patients with beriberi, and their health can be transformed within an hour of administration of the treatment. Thiamine occurs naturally in unrefined cereals and fresh foods, particularly fresh meat, legumes, green vegetables, fruit, and milk.