Risk factor intervention for health maintenance.

Risk factors for disease consist of (i) personal habits, such as cigarette smoking and excessive alcohol consumption, and (ii) bodily characteristics, such as hypertension and high serum cholesterol. Progress in identifying and quantifying risk factors is opening the way to the prevention of disease and maintenance of health. Systematic, controlled trials of intervention against risk factors are beginning to produce evidence on the extent of success in reducing both the factors and the mortality from associated diseases.