우리나라 성인 여성의 Na 섭취량 측정방법의 모색

Measurement of Na intake in Korean Adult Females

Dietary intakes of na include both the amount present in food materials (nondiscretionary Na intake) and the amount added during cooking and eating to increase salty taste and flavor (discretionary Na intake). In the present study, total Na intake was measured by duplicate food sample collected from each subject for 1 day, nondiscretionary Na intake was calculated by dietary intake record, optimum gustation of salt was measured of from pooled 3-day urine collection in healthy female college students, to measure Na intake more accurately and to find suitable method to estimate total Na intake. Mean values of total, discretionary and mondiscretionary Na intakes were 169.6 mEq, 46.2mEq, and 123.4mEq. respectively. Mean 24-hour urinary Na excretion was 137.9mEq., which was about 84.5% of total intake. Subjects with optimum gustation of salt equal to or higher than 0.5% had significantly higher total Na intake and urinary Na excretion compared to subjects with optimum gustation of salt lower than 5%. Total Na intake of subjects were significantly correlated with optimum gustation of salt, non-discretionary and discretionary Na intakes, and urinary Na excretion. Multiple regression analysis showed that the best estimate of total Na intake is obtained when both optimum gustation of salt and non-discredinary Na intake were used as independent variables (r=.7071). Among the equations using one independent variable, regression, equation with urinary Na excretion provides the best approximation (r=.6627) of total Na intake.