Beriberi

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Beriberi, diet-deficiency disease caused by a lack of vitamin B1. Chronic deficiency is known to cause two distinct forms of beriberi. When associated with low calorie intake and inactivity, the disease tends to affect the nervous system. This form, termed dry beriberi, is characterized by neuritis in the lower extremities, often with muscle atrophy, poor coordination, and eventually paralysis. The second form of beriberi, known as wet beriberi, is usually associated with extremely high activity levels and a high carbohydrate intake. Symptoms of wet beriberi include sweating, warm skin, and elevated heart rate; heart failure and death may follow.

Beriberi is especially prevalent in those parts of the world where the diet consists mainly of polished rice. Recovery is complete in about 50 percent of cases when adequate amounts of vitamin B1 are restored to the diet.

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