Patients were randomly assigned to an experimental group or to a usual-care group. Experimental-group patients were prescribed a lifestyle program including a low-fat vegetarian diet, moderate aerobic exercise, stress management training, stopping smoking, and group support. No animal products were allowed in the vegetarian diet except egg white and one cup per day of non-fat milk or yogurt. The diet contained approximately 10 percent of calories as fat. Control-group patients were not asked to make lifestyle changes. Coronary angiography was performed at baseline and at one year to assess progression or regression of disease. Patients were recruited into the trial between January 1986 and November 1988. The trial was supported prior to April 1989 from various sources other than the National Heart, Lung, and Blood Institute. Follow-up continued for four years.