S-54-4: DIETARY SALT INTAKE ASSESSED BY SPOT URINARY SODIUM EXCRETION FROM CHILD TO ADULTHOOD IN A JAPANESE TOWN

Abstract

In clinical practice, a high salt intake is strongly associated with elevation of blood pressure. To prevent and treat hypertension, it is important to restrict salt in one’s diet from child and adolescence. However, data are lacking regarding dietary salt intake from child to adulthood in general population. Therefore, we evaluated the dietary salt intake assessed by spot urinary sodium excretion from child to adulthood in a Japanese town. A total of 534 persons of both sexes, aged from 3 to 91 years were under study. The Tanaka formula was used to estimate 24-h urinary sodium excretion, which reflects salt intake. The average salt intake was 8.0 ± 2.7 g/day (n = 534); that of the men was 8.2 ± 2.8 g/day (n = 206), and that of the women was 7.8 ± 2.6 g/day (n = 249). When we assessed by age group, the average salt intake was 3.8 ± 2.2 g/day in 3 years old (n = 79), 6.8 ± 1.5 g/day in 11 years old (n = 36), 8.0 ± 1.5 g/day in 14 years old (n = 37), 8.6 ± 2.8 g/day in 20 s and 30 s (n = 37), 8.0 ± 1.7 g/day in 40 s (n = 24), 8.9 ± 2.2 g/day in 50 s (n = 32), 8.9 ± 2.1 g/day in 60 s (n = 108), 9.2 ± 1.9 g/day in 70 s (n = 182), and 9.0 ± 2.2 g/day in over 80 s (n = 22). Notably, dietary salt intake was over 6 g/day even in 11 years old. The salt intake was significantly higher in the older age group (P < 0.001 for trend) and was significantly associated with higher systolic and diastolic blood pressure. In conclusion, it is important to educate children, their parents, childcare professionals, and society about proper salt restriction and potassium supplementation, as well as to improve the food environment.