[Relationship of dietary intake of sodium, potassium, calcium and magnesium to blood pressure].

Dietary intake of sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) from measured food intake, and urinary Na and K excretions estimated by analyzing the second voided morning urine were analyzed for correlations to each other and to blood pressure in 57 males and 90 females (average age of 53 years). Significant positive correlations were found between systolic blood pressure and urinary Na/K ratio, dietary Ca/Mg ratio and body mass index after adjustment for age. Diastolic blood pressure was also positively correlated to these variables. By multiple regression analysis, the coefficients for age and urinary Na/K and dietary Ca/Mg ratios were all statistically significantly associated with systolic and diastolic blood pressure. Dietary Ca/Mg ratio was negatively correlated with rice, beans and fish intake, and urinary K excretion positively correlated with fish and green vegetable intakes by the same analysis. These data suggest that the dietary Ca/Mg ratio--but not magnesium singly--as well as aging and urinary Na/K ratio were among important factors related to blood pressure.