Effects of drinking water and total sodium intake on blood pressure

A cohort of 295 persons from a rural area of Michigan were studied to determine if a relationship exists between high levels of sodium in drinking water and blood pressure. Sodium in drinking water, dietary sodium intake, blood pressure, sodium excretion, height, and weight were measured. No significant relationships between daily mean sodium dietary intake, drinking water sodium, or sodium index (amount of drinking water sodium related to diet sodium intake), and mean blood pressure levels were found. A statistically significant relationship was found between 24-h urine sodium excretion and mean blood pressure for adults age greater than or equal to 18 yr (r = 0.239) and children age less than 18 yr (r = 0.359) and dietary intake and mean diastolic blood pressure in children only (r = 0.471). Furthermore, levels of sodium in drinking water were not related to blood pressure levels or presence of hypertension.