Tribes that exist on a very low salt intake while consuming large amounts of potassium, and whose members are quite small and thin, develop practically no hypertension. Within the Western world little correlation between sodium intake and blood pressure can be found in the untreated patient. However, as individuals with high-normal blood pressure develop further blood pressure elevation on sodium loading, those with a family history of hypertension or high-normal blood pressure should restrict their sodium intake. There is a modest amount of evidence to suggest that potassium protects against the blood pressure-raising effects of sodium. The case for sodium restriction is best demonstrated in the treated hypertensive patient. Modest sodium restriction will enable the treated hypertensive patient to obtain good blood pressure control with much less drug intake and, therefore, less drug side effect.