Research findings from prospective epidemiological studies in a number of populations in the United States over the past 40 years have convincingly established that elevated blood cholesterol, elevated blood pressure, and cigarette smoking are risk factors associated with accelerated development of myocardial infarction, sudden death, and death from coronary heart disease. These are not the only risk factors associated with premature development of CHD, but these factors are modifiable and provide a strong expectation that a reduction of these factors should have a beneficial result of reducing the rate of development of premature heart attacks.