[Relation between salt intake and blood pressure]

We investigated in a population group of 78 middle-aged men urinary sodium and potassium excretion per 24 hours under normal living conditions and the relationship to blood pressure. The mean urinary Na excretion in 24 hours was 241.3 mmol which corresponded to an intake of 14 g NaCl per day. The maximum NaCl consumption was as high as 30 g/day. The urinary Na excretion correlated in a linear fashion with the K excretion but not with the blood pressure. The blood pressure in the investigated group correlated with age, body mass index (kg/m2) and serum creatinine level. The body mass index and serum creatinine participated significantly in the blood pressure level, when multiple linear regression was used, where the urinary Na and K excretion per 24 hours were insignificant factors. In the investigated group a direct correlation of Na intake and blood pressure was not found, the investigation provided, however, information on the variability of urinary Na and K excretion/24 hours in the population and enables to estimate the necessary sample size to resolve this problem.