Studies of vitamin deficiencies have shown that adequate amounts of most vitamins are essential for normal resistance to infectious diseases.1 Attempts to determine the mechanism by which resistance is lowered in the presence of vitamin deficiency, however, have been unsuccessful. Data thus far reported indicate that antibody response is practically normal in vitamin deficient animals, suggesting the probability that the observed reduction in resistance is due to reduced phagocytic functions.
Careful quantitative studies of variations in phagocytic power under different nutritional conditions have been undertaken by Cottingham and Mills2 of the Laboratories of Experimental Medicine, University of Cincinnati. In their tests a standard dose of Micrococcus candidus was injected intraperitoneally into mice that had been maintained for several weeks on various partially deficient diets. Four hours later, smears were made of the peritoneal exudates. In a typical test control, mice were maintained at 68 F. for three weeks