Effects of a salt-restricted diet on the intake of other nutrients

Salt restriction, recommended as the first-line treatment of hypertension, has been proposed to lead to deficiencies in intakes of some other nutrients.

The aim of this study was to investigate the effects of salt restriction for 20 wk on the intake of other nutrients in free-living subjects with mildly elevated blood pressure.

Thirty-nine subjects (24 men, 15 women) aged 28-65 y with a mean daytime ambulatory diastolic blood pressure of 90-105 mm Hg and a diastolic blood pressure measured in a health care center of 95-115 mm Hg participated in the study. The subjects completed 4-d food records and their salt intake was measured by 24-h urinary sodium excretion. The subjects received both oral and written instructions from a clinical nutritionist on how to reduce their daily sodium chloride intake to <5 g/d but were instructed not to change their diet otherwise. The subjects were provided with low-salt bread during the salt-restriction period.

Few changes were found in nutrient intakes. In men, total energy intake decreased by 1059 kJ/d and alcohol, potassium, and vitamin D intakes decreased, but there were no significant changes in energy-adjusted potassium and vitamin D intakes. In women, total potassium intake increased, but the potassium density of the diet remained unchanged. Total selenium intake and energy-adjusted intake of selenium both decreased significantly in women.

Salt restriction can be undertaken in free-living hypertensive subjects without any untoward changes in the intake of other nutrients.