Beriberi is a nervous system ailment caused by a thiamine (vitamin B1) deficiency in the diet. Thiamine is involved in the breakdown of molecules such as glucose and is also found on the membranes of neurons. Symptoms of beriberi include severe lethargy and fatigue, together with complications affecting the cardiovascular, nervous, muscular, and gastrointestinal systems. The origin of the term is unclear, although several hypotheses have been suggested. One hypothesis is that it comes from a Sinhalese phrase meaning 'weak, weak' or 'I cannot, I cannot', the word being reduplicated for emphasis. Another hypothesis is that it is from the Arabic 'bhur-bhari', meaning 'sailor's asthma.' In 1630, a Dutch physician named Jacob Bonitus encountered the disease while working in Java. In the first known description of beriberi, he wrote, 'A certain very troublesome affliction, which attacks men, is called by the inhabitants beriberi (which means sheep).
Contributions by 220.127.116.11, Vapour, and Arcadian.