The study was intended to take advantage of the availability of patients at the three centers at the completion of the Hypertension Detection and Follow-up Program Study. These patients were enrolled as 'stepped-care' participants and had been treated with antihypertensive drugs for at least five years. The main objective of the study was to determine the contribution of dietary modification to maintenance of normal blood pressure after withdrawal of medication. Two types of diet change were followed: 1) reduction of sodium intake coupled with increased potassium intake; and 2) reduction of weight in the subgroups of patients that were obese.