thiamine /thī″əmin/ [Gk, theion, containing sulfur, amine, ammonia] , a water-soluble, crystalline compound of the B vitamin complex, essential for normal metabolism and health of the cardiovascular and nervous systems. Thiamine plays a key role in the metabolic breakdown of glucose to yield energy in body tissues. Rich sources are pork; organ meats; green leafy vegetables; legumes; sweet corn; egg yolk; cornmeal; brown rice; yeast; and the germ and husks of grains, berries, and nuts. It is not stored in the body and must be supplied daily. A deficiency of thiamine affects chiefly the nervous system, the circulation, and the GI tract. Symptoms include irritability, emotional disturbances, loss of appetite, multiple neuritis, increased pulse rate, dyspnea, reduced intestinal motility, and heart irregularities. Severe deficiency causes beriberi. Also called antiberiberi factor, antineuritic vitamin, vitamin B1. Also spelled thiamin.
