A study was conducted to assess the relationship between the zinc/copper ratio and risk factors (hypertension, obesity, elevated serum cholesterol and triglycerides, cigarette smoking, and exercise activity level) associated with susceptibility to cardiovascular disease. A questionnaire technique for assessment of physical activity was presented. The zinc/copper ratio was determined from the zinc and copper concentrations of hair samples obtained from sixty-four male subjects, ranging in age from 19 to 59 years. Correlation coefficients revealed no discernible relationship between either the zinc and copper content of hair, or the zinc/copper ratio obtained from these values. Serum cholesterol and triglyceride values, zinc concentrations in hair and the zinc/copper ratio were tested for significant differences associated with age. Statistical analysis indicated that these parameters were not significantly different. Such results were attributed to the wide range of variation within groups for this sample population. Data was not supportive of Klevay's altered zinc/copper ratio hypothesis as the major factor in the etiology of cardiovascular disease. / Ph. D.