Deleterious effects of salt intake other than effects on blood pressure

1. Salt intake is not only known to play an important role in determining blood pressure (BP) but has been shown to have other deleterious effects independent of BP. 2. Epidemiological and animal studies have provided evidence that salt intake may have an adverse effect on stroke mortality independent of BP. 3. Significant correlation between sodium excretion (as a measure of salt intake) and left ventricular (LV) hypertrophy has been shown in many clinical studies. Salt restriction has also been found to produce a significant reduction in LV mass. 4. In animal studies, salt restriction in uninephrectomized spontaneously hypertensive rats retarded renal glomerular injury and suppressed compensatory growth independent of hypertension. Moreover, a high sodium diet accelerated cerebral arterial disease even when no increases in BP could be detected. 5. Epidemiological data have shown an association between asthma mortality and regional purchases of table salt. Furthermore, dietary salt restriction in asthmatic patients results in improvement of symptomatology with lower consumption of bronchodilators. 6. Patients with essential hypertension are known to have increased urinary calcium excretion, and hypertension may be one factor that may increase the likelihood of osteoporosis. High salt intake is also associated with increased hydroxyproline excretion indicating increased resorption of bone. Sodium restriction reduces calcium excretion and may reduce bone demineralization and hip fractures in a similar manner to that seen with diuretics.