Subclinical Vitamin Deficiency V. The Assay of Subclinical Thiamin Deficiency

ExcerptINTRODUCTIONThe assay of subclinical thiamin deficiency is primarily a problem in defining changes in thiamin nutrition before signs or symptoms of deficiency make their appearance. Accomplishment of this end presupposes a knowledge of normal thiamin nutrition; that is, normal extracellular and intracellular thiamin concentrations, and the size and sequence of variation in these values which may precede the occurrence of clinical deficiency.1The purpose of the present study is to determine whether measurable changes in either extracellular or intracellular thiamin concentrations occur in subclinical thiamin deficiency. For comparison, observations are also reported on thiamin excretion and on pyruvate metabolism....