1985 Volume 38 Issue 4 Pages 259-264
Relatianship of Na, K and Na/K ratio estimated from dietary records with those determined by 24 hours urine samples was investigated in eight female students between the age of 21 and 22 years old attending the dietician course of Kagawa Nutrition College. Collection of 24 hours urine was undertaken for a week in both March and April, 1983.
All the subjects kept their own dietary records for 10 days, beginning on 3 days prior to urine collection.
The results obtained were as follows;
1) Individual coefficient of variance (standard deviation/mean value) in creatinine excretion in 24 hours urine samples during a week ranged from 4.2 to 27.8 per cent.
2) The mean value of Na estimated from dietary records was very close to that found in the 24 hours urine samples. The correlation coefficient of Na between the two methods on the same day was 0.44 (p<0.001).
3) The mean value of K estimated from dietary records was significantly higher than that found in the 24 hours urine samples. The correlation coefficient of K between the two methods on the same day was 0.32 (p<0.01).
4) The mean value of Na/K ratio estimated from dietary records was significantly lower than that found in the 24 hours urine samples.
The correlation coeffiient of Na/K ratio between the two methods on the same day was 0.42 (p<0.001).
5) Among all subjects, the figures of correlation coefficients of Na, K and Na/K ratio were higher in those whose coefficient of variance in creatinine excretion in 24 hours urine samples were less than 15 per cent.
