Vitamin B1 (Thiamine)

High levels of thiamine are rare but may occur if excessive amounts of the vitamin are consumed, either in supplements or from foods. 

Vitamin B1 deficiency can start out with fatigue, depression, irritability, sleep disturbances, GI disturbances from carbohydrates, and neuropathy (burning feet sensation). Deficiency is called beriberi. It can lead to rapid heart rate and heart enlargement. This could then cause breathing difficulties and congestive heart failure.

Beriberi can also cause mental and cognitive impairments when related to alcohol abuse. Some of these symptoms of vitamin deficiency include dementia, amnesia, confusion, abnormal eye movements, seizures and difficulty walking, 

The needs for vitamin B1 increase during pregnancy, breast feeding, strenuous activity, growth spurts and during a fever. 

Some specific causes of low vitamin B1 might be: 

- Poor dietary intake 

- Chronic alcohol consumption

- Anorexia

- Gastric bypass surgery

- Diabetes

- Dieting

- Consuming African silkworms or ferns (These foods contain an enzyme called thiaminase that destroys thiamine.)

- Consuming tea and coffee (decaffeinated or caffeinated) in large amounts (contains thiaminase)

- Consuming raw, fresh-water fish or raw shellfish (These foods contain thiaminase.)

- The use of diuretics

- Digestive disorders (Crohn’s disease, celiac disease, absorption of nutrient problems)

- Kidney dialysis

Vitamin B1, also called thiamine, is important for nervous system and muscle function. Thiamine acts as a coenzyme for carbohydrate and amino acid metabolism. It also is essential for the production of hydrochloric acid.