Zinc Deficiency in Man

In 1869, Raulin1first showed that zinc was essential for the growth ofAspergillus niger. In 1926, its essentiality for higher forms of plant life was established.2Todd and coworkers3(1934) showed that zinc was necessary for the growth and well being of the rat. In 1955, Tucker and Salmon4reported that Zinc cures and prevents parakeratosis in swine. The salient features of zinc deficiency in rats include anorexia, growth retardation, coarse and sparse hair, lymphopenia, testicular atrophy, hyperkeratosis, and acanthosis and parakeratosis of the skin, esophagus, and forestomach. In 1958, O'Dell et al5showed that zinc was required for growth and various other functions in birds. Zinc deficiency has been noted to occur in mice,6and deficiency of zinc has been produced experimentally in calves,7lambs,8dogs,9and young Japanese quails.10 Zinc deficiency in man, however, was once believed