Vitamin B1 (Thiamine)

Vitamin B1 (Thiamine) is a water-soluble vitamin crucial for carbohydrate metabolism (energy production) and nerve function. Severe deficiency causes beriberi (affecting heart and nervous system) or Wernicke-Korsakoff syndrome (in alcoholism). Marginal deficiency can cause fatigue, irritability, and poor concentration. Blood thiamine (often whole blood thiamine diphosphate) or functional tests (erythrocyte transketolase activity) assess status.