To elucidate the relationship between estimate of dairy salt intake and urinary salt excretion, and to develop a questionnaire for the estimation of dairy NaCI intake, we conducted area surveys on 62 females living in an agricultural district and 50 females living in a fishery district. Collected data were about all the food intakes in three days, all the urine through 24 hours, and life habits questionnaire. The correlation coefficient were 0.393 with highly statistical significance between urinary NaCI excretion and computed NaCI intake by food survey, while the salt scale of the life habits questionnaire was found to be higher correlated, 0.410, with the NaCI excretion. Moreover, by means of Quantification Theory I to obtain the most appropriate weights for categories of items of the salt scale, multiple correlation coefficient of the salt scale with urinary NaCI excretion became to be 0.504 with high significance. Finally, it was strongly suggested that the use of questionnaire must be a powerful tool to estimate the dairy salt intake in epidemiologic studies as well as food survey.
