beriberi

or vitamin B1

Nutritional disorder, with nerve and heart impairment, caused by thiamin deficiency. Its name is from the Sinhalese word for “extreme weakness.” Symptoms include fatigue, digestive problems, and limb numbness and weakness. Dry beriberi involves gradual long-nerve degeneration, with muscle atrophy and loss of reflexes. Wet beriberi is more acute, with edema from cardiac failure and poor circulation. Thiamin occurs widely in food but is lost in processing; a well-balanced diet high in unprocessed foods can prevent beriberi. In Western countries, chronic alcoholism is the most common cause.

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