Randomized. After three weeks on a control diet, subjects were randomized to the Protein Sparing Modified Fast Diet which provided 600 calories per day (1.5 grams per kilogram of ideal body weight of high quality protein plus 19 grams of fat) or to a 1200 calorie per day Balanced Deficit Diet. After 16 weeks in the weight-loss phase, subjects entered the maintenance program for 20 weeks. Both diets were supplemented with vitamins, minerals, and fluids. The Protein Sparing Modified Fast Diet was supplemented with 5 grams of salt given as bouillon to equal the salt intake of the Balanced Deficit Diet. Patients were followed for 24 months after the end of the weight loss phase. The primary endpoint was change in diastolic blood pressure. Individuals who continued to have diastolic pressures above 104 mm Hg following the initial 16 week treatment period were treated with antihypertensive drugs.