"Beriberi, the disease resulting from severe thiamin deficiency, was described in Chinese literature as early as 2600 B.C. Thiamin deficiency affects the cardiovascular, nervous, muscular, and gastrointestinal systems. Beriberi has been termed dry, wet, or cerebral, depending on the systems affected by severe thiamin deficiency. "

"Thiamine is found in a wide variety of foods at low concentrations. Yeast, yeast extract and pork are the most highly concentrated sources of thiamine. In general, cereal grains are the most important dietary sources of thiamine, by virtue of their ubiquity. Of these, whole grains contain more thiamine than refined grains, as thiamine is found mostly in the outer layers of the grain and in the germ (which are removed during the refining process)."

"A lack or deficiency of thiamin can cause weakness, fatigue, psychosis, and nerve damage. Thiamine deficiency in the United States is most often seen in those who abuse alcohol (alcoholism). A lot of alcohol makes it hard for the body to absorb thiamine from foods."